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Kim YJ, Oh DH, Song BR, Heo EJ, Lim JS, Moon JS, Park HJ, Wee SH, Sung K. Molecular Characterization, Antibiotic Resistance, and Virulence Factors of Methicillin-Resistant Staphylococcus aureus Strains Isolated from Imported and Domestic Meat in Korea. Foodborne Pathog Dis 2015; 12:390-8. [PMID: 25789540 DOI: 10.1089/fpd.2014.1885] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
During a nationwide surveillance in Korea, 13 methicillin-resistant Staphylococcus aureus (MRSA) strains were isolated from imported and domestic meat between 2009 and 2011. The predominant MRSA genotype was SCCmec type V, and only two agr types (I and II) were found. Unexpectedly, sequence type ST72 comprised more than 50% of the isolates; this is the first instance of type ST72 in food from Canada. Two Spanish pork isolates were ST398, which caused human disease in Europe, and they carried leukotoxin genes, lukS, lukF, and lukE-lukD. Furthermore, P71 and P6 harbored all of the known leukocidin genes, lukS-lukF-lukE-lukD-lukM. Our collected MRSA strains were multidrug resistant with various antimicrobial and heavy-metal resistance genes. Toxin genes that are commonly found in clinical MRSA also were detected in our meat strains. One MRSA strain exhibited an uncommon type of enterotoxin, sec-see-seg-sei-sel-sem-sen-seo-sep. Plasmids (1.5-15.0 kb) were found in 12 of the 13 MRSA isolates. Repetitive sequence-based polymerase chain reaction of the genomic DNA showed 3 clusters with 95% similarity. The presence of multidrug-resistant and toxigenic MRSA in meat products suggests that comprehensive surveillance should be continued for imported meats in Korea.
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Affiliation(s)
- Young Jo Kim
- 1 Food Consumption Safety Division, Ministry of Food and Drug Safety , Cheongwon, Korea
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Fabres-Klein MH, Caizer Santos MJ, Contelli Klein R, Nunes de Souza G, de Oliveira Barros Ribon A. An association between milk and slime increases biofilm production by bovine Staphylococcus aureus. BMC Vet Res 2015; 11:3. [PMID: 25591667 PMCID: PMC4311514 DOI: 10.1186/s12917-015-0319-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 01/05/2015] [Indexed: 11/10/2022] Open
Abstract
Background Staphylococcus aureus is associated with chronic mastitis in cattle, and disease manifestation is usually refractory to antibiotic therapy. Biofilm production is a key element of S. aureus pathogenesis and may contribute to the treatment failure that is consistently reported by veterinarians. Minas Gerais State is the largest milk-producing state in Brazil, and the characterization of bacterial isolates is an important aspect of disease control for dairy farmers. Here, we investigated the potential of S. aureus isolated from bovine mastitis to produce slime and biofilm in a skim-milk medium and classified the isolates according to their agr type. Results Slime was detected using the Congo Red agar (CRA) test in 35.18% (19/54) of the strains; however, 87.04% (47/54) of the strains were considered biofilm-positive based on crystal violet staining. Compared to TSB supplemented with 0.25% glucose, skim milk significantly increased the production of biofilm, but this effect was only observed in slime-producing strains. The bacteria belonged to agr groups I (12/54), II (34/54), III (6/54), and IV (2/54), and bacteria in agr group III were found to be stronger biofilm producers than those in groups I and II. Again, milk had a significant influence only on slime-positive agr I and II isolates, revealing an association between milk and slime. Conclusions The present study demonstrated that skim-milk medium and slime production are two factors that together influence biofilm formation by bovine strains of S. aureus. A predominance of bacteria belonging to agr group II was observed, and bacteria from agr group III showed the highest proportion of biofilm producers. The majority of bacteria characterized in this study formed biofilm in milk, which suggests that biofilm formation has an important role in the virulence of S. aureus isolated from bovine intramammary infections.
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Affiliation(s)
- Mary Hellen Fabres-Klein
- Departamento de Bioquímica e Biologia Molecular, Laboratório de Biotecnologia Molecular, Universidade Federal de Viçosa, Viçosa, 36570-000, Minas Gerais, Brazil.
| | - Mário Junior Caizer Santos
- Departamento de Bioquímica e Biologia Molecular, Laboratório de Biotecnologia Molecular, Universidade Federal de Viçosa, Viçosa, 36570-000, Minas Gerais, Brazil.
| | - Raphael Contelli Klein
- Departamento de Bioquímica e Biologia Molecular, Laboratório de Biotecnologia Molecular, Universidade Federal de Viçosa, Viçosa, 36570-000, Minas Gerais, Brazil.
| | | | - Andrea de Oliveira Barros Ribon
- Departamento de Bioquímica e Biologia Molecular, Laboratório de Biotecnologia Molecular, Universidade Federal de Viçosa, Viçosa, 36570-000, Minas Gerais, Brazil.
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Park KH, Chong YP, Kim SH, Lee SO, Choi SH, Lee MS, Jeong JY, Woo JH, Kim YS. Community-associated MRSA strain ST72-SCCmecIV causing bloodstream infections: clinical outcomes and bacterial virulence factors. J Antimicrob Chemother 2014; 70:1185-92. [PMID: 25433004 DOI: 10.1093/jac/dku475] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Community-associated MRSA (CA-MRSA) has emerged in the community and has recently been spreading in healthcare settings. The objectives of this study were to evaluate the clinical outcomes and bacterial virulence factors of the Korean CA-MRSA (ST72-SCCmecIV) strain, which causes bloodstream infections. METHODS All adult patients with MRSA bacteraemia were prospectively enrolled. Clinical outcomes, microbiological characteristics and 40 bacterial virulence factors were evaluated. RESULTS Of the 352 typed MRSA isolates, 342 isolates (97.2%) belonged to three Panton-Valentine leucocidin-negative strains: ST5-SCCmecII (70.2%), ST72-SCCmecIV (22.4%) and ST239-SCCmecIII (4.6%). The remaining 10 (2.8%) isolates from minor strains were excluded from the final analysis. After controlling for several confounding factors, ST72-SCCmecIV was associated with the lowest mortality (compared with ST5-SCCmecII, adjusted OR=0.26; 95% CI=0.13-0.54). However, MRSA isolates with vancomycin MICs of ≥ 1.5 mg/L were more common in ST72-SCCmecIV compared with ST5-SCCmecII (84.8% versus 66.7%; P=0.002). Reduced vancomycin susceptibility and vancomycin heteroresistance were not associated with mortality. Compared with ST5-SCCmecII isolates, ST72-SCCmecIV isolates were less likely to harbour multiple virulence genes. Of these genes, three staphylococcal superantigen genes were associated with mortality: sec (OR=2.31; P=0.002), sel (OR=2.55; P=0.003) and tst (OR=2.76; P<0.001). CONCLUSIONS After controlling for confounding factors, ST72-SCCmecIV was independently associated with lower mortality compared with ST5-SCCmecII, suggesting this CA-MRSA strain to be of lower virulence. The lack of virulence genes, including staphylococcal superantigen genes, may play a role in the lower virulence of this strain.
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Affiliation(s)
- Ki-Ho Park
- Division of Infectious Diseases, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, Republic of Korea
| | - Yong Pil Chong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Sung-Han Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang-Oh Lee
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang-Ho Choi
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Mi Suk Lee
- Division of Infectious Diseases, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, Republic of Korea
| | - Jin-Yong Jeong
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Hee Woo
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yang Soo Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
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Paniagua-Contreras GL, Monroy-Pérez E, Vaca-Paniagua F, Rodríguez-Moctezuma JR, Vaca S. Expression of enterotoxin-coding genes in methicillin-resistant Staphylococcus aureus strains isolated from Mexican haemodialysis patients. Ann Clin Microbiol Antimicrob 2014; 13:55. [PMID: 25421262 PMCID: PMC4245768 DOI: 10.1186/s12941-014-0055-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 11/05/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) causes severe catheter-related infections in haemodialysis patients ranging from local-site infections and septic thrombophlebitis to bacteraemia but the associated virulence factors and exotoxins remain unclear. FINDINGS We employed an in vitro infection model using reconstituted human epithelium (RHE) to analyse the expression profiles of 4 virulence genes and 12 exotoxin-coding virulence genes in 21 MRSA strains isolated from catheter-related infections in 21 Mexican patients undergoing haemodialysis. All 21 strains (100%) expressed the seg, seh, sei, eta, etb, or hla genes coding staphylococcal toxins. Eleven MRSA strains (52.3%) expressed the sea gene coding staphylococcal enterotoxin A, and two strains (9.5%) expressed the v8 gene coding serine protease. The tst, chp, and arcA genes coding toxic shock syndrome toxin 1, chemotaxis inhibitory protein, and arginine deiminase, respectively, were expressed in separate single strains (4.7%). The most frequent expression profile (42.8% of the strains) comprised seg, seh, sei, eta, etb, and hla. CONCLUSION It is likely that the SEG, SEH, SEI, ETA, ETB, and Hla toxins may play a role in MRSA catheter-related infections. Consideration of these toxins in the development of a vaccine or as targets for monoclonal antibody therapy could provide an improved therapeutic strategy for the treatment of catheter-related infections in haemodialysis patients.
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Affiliation(s)
- Gloria Luz Paniagua-Contreras
- FES-Iztacala, Universidad Nacional Autónoma de Mexico, Av de Los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, Edo de México, México.
| | - Eric Monroy-Pérez
- FES-Iztacala, Universidad Nacional Autónoma de Mexico, Av de Los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, Edo de México, México.
| | - Felipe Vaca-Paniagua
- FES-Iztacala, Universidad Nacional Autónoma de Mexico, Av de Los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, Edo de México, México.
| | | | - Sergio Vaca
- FES-Iztacala, Universidad Nacional Autónoma de Mexico, Av de Los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, Edo de México, México.
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Characterization of alpha-toxin hla gene variants, alpha-toxin expression levels, and levels of antibody to alpha-toxin in hemodialysis and postsurgical patients with Staphylococcus aureus bacteremia. J Clin Microbiol 2014; 53:227-36. [PMID: 25392350 DOI: 10.1128/jcm.02023-14] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alpha-toxin is a major Staphylococcus aureus virulence factor. This study evaluated potential relationships between in vitro alpha-toxin expression of S. aureus bloodstream isolates, anti-alpha-toxin antibody in serum of patients with S. aureus bacteremia (SAB), and clinical outcomes in 100 hemodialysis and 100 postsurgical SAB patients. Isolates underwent spa typing and hla sequencing. Serum anti-alpha-toxin IgG and neutralizing antibody levels were measured by using an enzyme-linked immunosorbent assay and a red blood cell (RBC)-based hemolysis neutralization assay. Neutralization of alpha-toxin by an anti-alpha-toxin monoclonal antibody (MAb MEDI4893) was tested in an RBC-based lysis assay. Most isolates encoded hla (197/200; 98.5%) and expressed alpha-toxin (173/200; 86.5%). In vitro alpha-toxin levels were inversely associated with survival (cure, 2.19 μg/ml, versus failure, 1.09 μg/ml; P < 0.01). Both neutralizing (hemodialysis, 1.26 IU/ml, versus postsurgical, 0.95; P < 0.05) and IgG (hemodialysis, 1.94 IU/ml, versus postsurgical, 1.27; P < 0.05) antibody levels were higher in the hemodialysis population. Antibody levels were also significantly higher in patients infected with alpha-toxin-expressing S. aureus isolates (P < 0.05). Levels of both neutralizing antibodies and IgG were similar among patients who were cured and those not cured (failures). Sequence analysis of hla revealed 12 distinct hla genotypes, and all genotypic variants were susceptible to a neutralizing monoclonal antibody in clinical development (MEDI4893). These data demonstrate that alpha-toxin is highly conserved in clinical S. aureus isolates. Higher in vitro alpha-toxin levels were associated with a positive clinical outcome. Although patients infected with alpha-toxin-producing S. aureus exhibited higher anti-alpha-toxin antibody levels, these levels were not associated with a better clinical outcome in this study.
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Kalinka J, Hachmeister M, Geraci J, Sordelli D, Hansen U, Niemann S, Oetermann S, Peters G, Löffler B, Tuchscherr L. Staphylococcus aureus isolates from chronic osteomyelitis are characterized by high host cell invasion and intracellular adaptation, but still induce inflammation. Int J Med Microbiol 2014; 304:1038-49. [DOI: 10.1016/j.ijmm.2014.07.013] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 06/23/2014] [Accepted: 07/21/2014] [Indexed: 01/06/2023] Open
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Chung JW, Karau MJ, Greenwood-Quaintance KE, Ballard AD, Tilahun A, Khaleghi SR, David CS, Patel R, Rajagopalan G. Superantigen profiling of Staphylococcus aureus infective endocarditis isolates. Diagn Microbiol Infect Dis 2014; 79:119-24. [PMID: 24745820 DOI: 10.1016/j.diagmicrobio.2014.03.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 03/05/2014] [Accepted: 03/09/2014] [Indexed: 12/20/2022]
Abstract
The frequency of superantigen production among Staphylococcus aureus isolates associated with endocarditis is not well defined. We tested 154 S. aureus isolates from definite infective endocarditis cases for the presence of staphylococcal enterotoxins A-E, H, and TSST-1 by PCR, enzyme-linked immunosorbent assay, and using an HLA-DR3 transgenic mouse splenocyte proliferation assay. Sixty-three isolates (50.8%) tested positive for at least 1 superantigen gene, with 21 (16.9%) testing positive for more than 2. tst (28.6%) was most common, followed by seb (27%), sea (22.2%), sed (20.6%), see (17.5%), and sec (11.1%). Of 41 methicillin-resistant S. aureus, 21 had superantigen genes, with sed being more frequently detected in this group compared to methicillin-susceptible S. aureus (P < 0.05). Superantigen genes were not associated with mortality (P = 0.81). 75% of PCR-positive isolates induced robust splenocyte proliferation. Overall, more than half of S. aureus isolates causing endocarditis carry superantigen genes, of which most are functional.
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Affiliation(s)
- Jin-Won Chung
- Divisions of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA; Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Melissa J Karau
- Divisions of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Kerryl E Greenwood-Quaintance
- Divisions of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Alessandro D Ballard
- Divisions of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Ashenafi Tilahun
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | | | - Chella S David
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Robin Patel
- Divisions of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA; Division of Infectious Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Govindarajan Rajagopalan
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA; Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA.
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Paul SK, Ghosh S, Kawaguchiya M, Urushibara N, Hossain MA, Ahmed S, Mahmud C, Jilani MSA, Haq JA, Ahmed AA, Kobayashi N. Detection and genetic characterization of PVL-positive ST8-MRSA-IVa and exfoliative toxin D-positive European CA-MRSA-Like ST1931 (CC80) MRSA-IVa strains in Bangladesh. Microb Drug Resist 2014; 20:325-36. [PMID: 24552553 DOI: 10.1089/mdr.2013.0153] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Severe skin lesions caused by Staphylococcus aureus infection are associated with production from bacterial cells of Panton-Valentine leukocidin (PVL), a typical virulence factor of community-acquired methicillin-resistant S. aureus (CA-MRSA), as well as other toxins represented by exfoliative toxins. Through a retrospective study of 26 S. aureus strains isolated from skin lesions of diabetic patients admitted to a hospital in Bangladesh, 2 PVL-gene-positive MRSA-IVa strains and 8 PVL-negative, exfoliative toxin D (ETD) gene (etd)-positive MRSA-IVa strains were isolated. A PVL-positive MRSA-IVa strain had a type I arginine catabolic mobile element (ACME), belonged to ST8/agr-type I/spa-type t121 (a variant of t008), and harbored blaZ, tet(K), msrA, and aph(3')-IIIa, which are mostly typical characteristics found in USA300, a predominant CA-MRSA clone in the United States. Another PVL-positive MRSA strain, belonging to ST1929 (CC88)/agr-type III/spa-type t3341, was negative for ACME, but possessed blaZ and tet(K). The etd-positive MRSA-IVa strains possessed the epidermal cell differentiation inhibitor B (EDIN-B)-encoding gene (edinB) and belonged to ST1931 (CC80)/agr-type III/spa-type t11023 (a variant of t044), which was genetic trait similar to that of the European CA-MRSA ST80 clone. However, unlike the European ST80 strains, the etd-positive MRSA strains detected in the present study harbored seb, sek, and seq, while they were negative for tet(K), aph(3')-IIIa, and fusB, showing susceptibility to fusidic acid. These findings suggested that etd-positive ST1931 MRSA strains belong to the same lineage as the European ST80 MRSA clone, evolving from a common ancestral clone via acquisition of a different pathogenicity island. This is the first report of a USA300-like MRSA-IV strain, PVL-positive ST1929 (CC88) MRSA-IV, and European ST80 CA-MRSA-like etd-positive ST1931 (CC80) MRSA-IV strains isolated in Bangladesh.
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Affiliation(s)
- Shyamal Kumar Paul
- 1 Department of Microbiology, Mymensingh Medical College , Mymensingh, Bangladesh
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Paniagua-Contreras G, Monroy-Pérez E, Gutiérrez-Lucas R, Sainz-Espuñes T, Bustos-Martínez J, Vaca S. Genotypic characterization of methicillin-resistant Staphylococcus aureus strains isolated from the anterior nares and catheter of ambulatory hemodialysis patients in Mexico. Folia Microbiol (Praha) 2014; 59:295-302. [DOI: 10.1007/s12223-013-0300-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 12/27/2013] [Indexed: 10/25/2022]
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Paniagua-Contreras GL, Monroy-Pérez E, Vaca-Paniagua F, Rodríguez-Moctezuma JR, Negrete-Abascal E, Vaca S. Implementation of a novel in vitro model of infection of reconstituted human epithelium for expression of virulence genes in methicillin-resistant Staphylococcus aureus strains isolated from catheter-related infections in Mexico. Ann Clin Microbiol Antimicrob 2014; 13:6. [PMID: 24405688 PMCID: PMC3905915 DOI: 10.1186/1476-0711-13-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Accepted: 12/22/2013] [Indexed: 11/10/2022] Open
Abstract
Background Methicillin-resistant Staphylococcus aureus (MRSA) are clinically relevant pathogens that cause severe catheter-related nosocomial infections driven by several virulence factors. Methods We implemented a novel model of infection in vitro of reconstituted human epithelium (RHE) to analyze the expression patterns of virulence genes in 21 MRSA strains isolated from catheter-related infections in Mexican patients undergoing haemodialysis. We also determined the phenotypic and genotypic co-occurrence of antibiotic- and disinfectant-resistance traits in the S. aureus strains, which were also analysed by pulsed-field-gel electrophoresis (PFGE). Results In this study, MRSA strains isolated from haemodialysis catheter-related infections expressed virulence markers that mediate adhesion to, and invasion of, RHE. The most frequent pattern of expression (present in 47.6% of the strains) was as follows: fnbA, fnbB, spa, clfA, clfB, cna, bbp, ebps, eap, sdrC, sdrD, sdrE, efb, icaA, and agr. Seventy-one percent of the strains harboured the antibiotic- and disinfectant-resistance genes ermA, ermB, tet(M), tet(K), blaZ, qacA, qacB, and qacC. PFGE of the isolated MRSA revealed three identical strains and two pairs of identical strains. The strains with identical PFGE patterns showed the same phenotypes and genotypes, including the same spa type (t895), suggesting hospital personnel manipulating the haemodialysis equipment could be the source of catheter contamination. Conclusion These findings help define the prevalence of MRSA virulence factors in catheter-related infections. Some of the products of the expressed genes that we detected in this work may serve as potential antigens for inclusion in a vaccine for the prevention of MRSA-catheter-related infections.
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Affiliation(s)
| | | | | | | | | | - Sergio Vaca
- FES-Iztacala, Universidad Nacional Autónoma de México, Av, de Los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, Edo, de México, México.
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Atshan SS, Nor Shamsudin M, Lung LTT, Sekawi Z, Pei Pei C, Karunanidhi A, Jeevajothi Nathan J, Mateg Ali A, Ghaznavi-Rad E, Abduljaleel SA, Awang Hamat R. Genotypically different clones of Staphylococcus aureus are diverse in the antimicrobial susceptibility patterns and biofilm formations. BIOMED RESEARCH INTERNATIONAL 2013; 2013:515712. [PMID: 24455699 PMCID: PMC3886620 DOI: 10.1155/2013/515712] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 10/04/2013] [Indexed: 11/21/2022]
Abstract
This study evaluated whether genotypically different clinical isolates of S. aureus have similar susceptibilities to individual antibiotics. It further aims to check the impact of biofilm on the in vitro activity of vancomycin, daptomycin, linezolid, and tigecycline against S. aureus clones. The study used a total of 60 different clinical MSSA and MRSA isolates. Susceptibilities were performed in planktonic cultures by macrobroth dilution and epsilon-test (E test) system. Biofilm production was determined using an adherent plate assay. The efficacy of antimicrobial activities against biofilms formation was checked using confocal laser scanning microscopy (CLSM). The study found that similar and different spa, MLST, and SCCmec types displayed high variation in their susceptibilities to antibiotics with tigecycline and daptomycin being the most effective. The biofilms were found resistant to high concentrations of most antibiotics tested with daptomycin being the most effective drug used in adhesive biofilms. A considerable difference exists among similar and various clone types against antibiotics tested. This variation could have contributed to the degree of virulence even within the same clonal genotype and enhanced heterogeneity in the infection potential. Thus, the development of a rapid and precise identification profile for each clone in human infections is important.
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Affiliation(s)
- Salman Sahab Atshan
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
- Department of Medical Microbiology, Basrah University, Basrah, Iraq
| | - Mariana Nor Shamsudin
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
- Laboratory of Marine Science and Aquaculture, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Leslie Than Thian Lung
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Zamberi Sekawi
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Chong Pei Pei
- Department of Biomedical Sciences, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Arunkumar Karunanidhi
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Jayakayatri Jeevajothi Nathan
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Alreshidi Mateg Ali
- Department of Biomedical Sciences, Faculty of Medicine and Health Science, Al Bukacyriyah, Saudi Arabia
| | | | | | - Rukman Awang Hamat
- Laboratory of Medical Microbiology and Parasitology, Faculty of Medicine and Health Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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Yoong P, Torres VJ. The effects of Staphylococcus aureus leukotoxins on the host: cell lysis and beyond. Curr Opin Microbiol 2013; 16:63-9. [PMID: 23466211 DOI: 10.1016/j.mib.2013.01.012] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 12/03/2012] [Accepted: 01/28/2013] [Indexed: 12/24/2022]
Abstract
The success of Staphylococcus aureus as a leading cause of deadly hospital-acquired and community-acquired infections is attributed to its high-level resistance to most antibiotics, and the multitude of virulence factors it elaborates. Most clinical isolates produce up to four bi-component pore-forming toxins capable of lysing cells of the immune system. Subtle differences in activity and target range of each leukotoxin suggest that these toxins are not redundant, but instead may have specialized functions in attacking and/or evading host defenses. In turn, the host has developed countermeasures recognizing sublytic levels of leukotoxins as signals to activate protective immune defenses. The opposing cytotoxic and immune-activating effects of leukotoxins on host cells make for a complex dynamic between S. aureus and the host.
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Affiliation(s)
- Pauline Yoong
- Department of Microbiology, New York University School of Medicine, United States
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Sina H, Ahoyo TA, Moussaoui W, Keller D, Bankolé HS, Barogui Y, Stienstra Y, Kotchoni SO, Prévost G, Baba-Moussa L. Variability of antibiotic susceptibility and toxin production of Staphylococcus aureus strains isolated from skin, soft tissue, and bone related infections. BMC Microbiol 2013; 13:188. [PMID: 23924370 PMCID: PMC3750628 DOI: 10.1186/1471-2180-13-188] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 08/07/2013] [Indexed: 11/27/2022] Open
Abstract
Background Staphylococcus aureus is an opportunistic commensal bacterium that mostly colonizes the skin and soft tissues. The pathogenicity of S. aureus is due to both its ability to resist antibiotics, and the production of toxins. Here, we characterize a group of genes responsible for toxin production and antibiotic resistance of S. aureus strains isolated from skin, soft tissue, and bone related infections. Results A total of 136 S. aureus strains were collected from five different types of infection: furuncles, pyomyositis, abscesses, Buruli ulcers, and osteomyelitis, from hospital admissions and out-patients in Benin. All strains were resistant to benzyl penicillin, while 25% were resistant to methicillin, and all showed sensitivity to vancomycin. Panton-Valentine leukocidin (PVL) was the most commonly produced virulence factor (70%), followed by staphylococcal enterotoxin B (44%). Exfoliative toxin B was produced by 1.3% of the strains, and was only found in isolates from Buruli ulcers. The tsst-1, sec, and seh genes were rarely detected (≤1%). Conclusions This study provides new insight into the prevalence of toxin and antibiotic resistance genes in S. aureus strains responsible for skin, soft tissue, and bone infections. Our results showed that PVL was strongly associated with pyomyositis and osteomyelitis, and that there is a high prevalence of PVL-MRSA skin infections in Benin.
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Affiliation(s)
- Haziz Sina
- Laboratoire de Biologie et de Typage Moléculaire en Microbiologie, Faculté des Sciences et Techniques/Université d'Abomey-Calavi, Cotonou, Benin
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Molecular and clinical characteristics of clonal complex 59 methicillin-resistant Staphylococcus aureus infections in Mainland China. PLoS One 2013; 8:e70602. [PMID: 23950969 PMCID: PMC3737374 DOI: 10.1371/journal.pone.0070602] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 06/21/2013] [Indexed: 01/06/2023] Open
Abstract
Detailed molecular analyses of Clonal Complex 59 (CC59) methicillin-resistant Staphylococcus aureus (MRSA) isolates from children in seven major cities across Mainland China were examined. A total of 110 CC59 isolates from invasive and non-invasive diseases were analyzed by multilocus sequence typing (MLST), Staphylococcus cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) typing and pulsed-field gel electrophoresis (PFGE). Antibiotics susceptibilities, carriage of plasmids and 42 virulence genes and the expression of virulence factors were examined. ST59 (101/110, 91.8%) was the predominant sequence type (ST), while single locus variants (SLVs) belonging to ST338 (8/110, 7.3%) and ST375 (1/110, 0.9%) were obtained. Three SCCmec types were found, namely type III (2.7%), type IV (74.5%) and type V (22.7%). Seven spa types including t437, which accounted for 87.3%, were determined. Thirteen PFGE types were obtained. PFGE types A and B were the major types totally accounting for 81.8%. The dominant clone was ST59-t437-IVa (65.5%), followed by ST59-t437-V (14.5%). The positive rate of luks-PV and lukF-PV PVL encoding (pvl) gene was 55.5%. Plasmids were detected in 83.6% (92/110) of the strains. The plasmid size ranging from 23.4 kb to 50 kb was most prevalent which accounted for 83.7% (77/92). A significantly lower expression of hla was found in ST59-t437-IVa compared with ST59-t437-V. Among the 110 cases, 61.8% of the patients were less than 1 year old. A total of 90 cases (81.8%) were community-associated (CA) infections whereas 20 cases (18.2%) were hospital-associated (HA) infections. Out of the 110 patients, 36.4% (40/110) were diagnosed with invasive infectious diseases in which ST59-t437-IVa accounted for 67.5% (27/40). In brief, ST59-t437-IVa was proved as the dominant clone in CC59 MRSA strains. The carriage rate of pvl gene was high. CC59 MRSA could result in CA and HA infections. The majortiy of MRSA infection children were in young age.
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Zaidi T, Zaidi T, Yoong P, Pier GB. Staphylococcus aureus corneal infections: effect of the Panton-Valentine leukocidin (PVL) and antibody to PVL on virulence and pathology. Invest Ophthalmol Vis Sci 2013; 54:4430-8. [PMID: 23737477 DOI: 10.1167/iovs.13-11701] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
PURPOSE Community-associated methicillin-resistant Staphylococcus aureus strains expressing Panton-Valentine leukocidin (PVL) are associated with severe skin and soft tissue infections, necrotizing pneumonia, and eye infections. We determined PVL's toxicity on infected mouse and cultured human corneal epithelial cells and the role of PVL and antibody to PVL in pathogenesis of murine keratitis. METHODS Cytotoxicity on corneas and corneal epithelial cells was evaluated by LDH assays. Scratched corneas of female A/J mice were inoculated with approximately 10⁷ CFU/eye of either WT S. aureus, isogenic ΔPVL, or strains overproducing PVL. Antibodies to PVL or control sera were topically applied to infected corneas 0, 24, and 32 hours postinfection, corneas scored for pathology and tissue levels of S. aureus were determined. RESULTS PVL expression augmented the cytotoxicity of S. aureus on infected mouse corneas and human cultured corneal epithelial cells. Variable effects on leukocyte recruitment, pathogenesis, and immunity were obtained in the in vivo studies. Inactivation of PVL in USA300 strains caused reduced pathology and bacterial counts. Results were variable when comparing WT and ΔPVL USA400 strains, while USA400 strains overproducing PVL caused increased bacterial burdens. Topical treatment with polyclonal antibody to PVL yielded significant reductions in corneal pathology and bacterial CFU in corneas infected with USA300 strains, whereas effects were inconsistent in eyes infected with USA400 strains. CONCLUSIONS PVL enhanced the virulence of a subset of MRSA strains in a keratitis model. Coupled with a variable effect of antibody treatment, it appears that PVL plays an inconsistent role in pathogenesis and immunity to S. aureus corneal infection.
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Affiliation(s)
- Tanweer Zaidi
- Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Uhlemann AC, Hafer C, Miko BA, Sowash MG, Sullivan SB, Shu Q, Lowy FD. Emergence of sequence type 398 as a community- and healthcare-associated methicillin-susceptible staphylococcus aureus in northern Manhattan. Clin Infect Dis 2013; 57:700-3. [PMID: 23728142 DOI: 10.1093/cid/cit375] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The methicillin-susceptible Staphylococcus aureus (MSSA) clone sequence type (ST) 398 has increasingly been identified as a pathogen in diverse geographic settings, yet its epidemiology remains incompletely understood. In this case-control study of MSSA infections, we identified ST398 MSSA as both a major community- and hospital-associated MSSA pathogen in the Dominican neighborhood of northern Manhattan.
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Affiliation(s)
- Anne-Catrin Uhlemann
- Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, 630 W 168th St, New York, NY 10032, USA.
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Li S, Sun J, Zhang J, Li X, Tao X, Wang L, Sun M, Liu Y, Li J, Qiao Y, Yu S, Yao K, Yang Y, Shen X. Comparative analysis of the virulence characteristics of epidemic methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from Chinese children: ST59 MRSA highly expresses core gene-encoded toxin. APMIS 2013; 122:101-14. [PMID: 23710711 DOI: 10.1111/apm.12105] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 03/07/2013] [Indexed: 11/28/2022]
Abstract
This study aims to investigate the prevalence of a novel cell wall-anchored protein gene, sasX, and to obtain information on the genetic basis for the pathogenic potential of the MRSA strains isolated from Chinese children. The molecular and virulence characteristics of the clinical strains were analyzed. Twenty-two sequence types (STs) were obtained, with six epidemic clones ST59, ST239, ST1, ST910, ST88, and ST338 accounting for 35.8, 22, 6.6, 6.6, 5.3, and 4.1% respectively. The expression levels of hla, psmα, and RNAIII were higher in ST59 than in other STs (p < 0.05). The sasX gene was detected in 26 (10.7%) MRSA isolates. ST239-MRSA-SCCmecIII-t037 (61.5%) was the predominant sasX-positive MRSA clone. The expressions of PSMα and RNAIII were higher in sasX-positive ST239 isolates than in sasX-negative ST239 ones (p < 0.01). Notably, the percentage of invasive infection in infections caused by sasX-positive ST239 MRSA was higher than that by sasX-negative ST239 MRSA (p = 0.008). This study indicated that ST59 was the predominant clone in the MRSA isolates obtained from Chinese children and might have stronger pathogenic potential. The prevalence of the sasX gene in the MRSA isolates from children was relatively low. Furthermore, the sasX gene might be related to the expressions of PSMα and RNAIII and infection invasiveness.
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Affiliation(s)
- Shipeng Li
- Key Laboratory of Major Diseases in Children and National Key Discipline of Pediatrics, Ministry of Education, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing
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Molecular epidemiology and characterization of virulence genes of community-acquired and hospital-acquired methicillin-resistant Staphylococcus aureus isolates in Colombia. Int J Infect Dis 2013; 17:e744-9. [PMID: 23623704 DOI: 10.1016/j.ijid.2013.02.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Revised: 02/22/2013] [Accepted: 02/28/2013] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To determine the molecular epidemiology and presence of virulence genes in community-acquired (CA) and hospital-acquired (HA) methicillin-resistant Staphylococcus aureus (MRSA) isolates and their relationship to clinical outcomes. METHODS An observational and prospective study of infections caused by MRSA was conducted between June 2006 and December 2007 across seven hospitals in three Colombian cities. MRSA isolates were analyzed for SCCmec. Also, pulsed-field gel electrophoresis and multilocus sequence typing were performed and 25 virulence genes were identified. RESULTS Two hundred and seventy isolates were collected from 262 adult hospital patients with MRSA infections. Overall, 68% of the isolates were classified as HA-MRSA and 32% as CA-MRSA. We identified differences in the patterns of virulence genes: 85% of HA-MRSA isolates possessed the enterotoxin gene cluster (egc), whereas 92% of CA-MRSA isolates possessed the lukF-PV/lukS-PV genes. Multivariate analysis showed an increased risk of mortality for seg (p=0.001, odds ratio 4.73) and a protective effect for eta (p=0.018, odds ratio 0.33). CONCLUSIONS Our study confirms that three clones of MRSA predominantly circulate in Colombia: a Chilean clone, a pediatric clone that causes HA-MRSA infections, and a USA300-related clone (SCCmec IVc) in CA-MRSA infections, which differ in the content of clinically important virulence genes. This study confirms that PVL is not a determinant of severity or mortality in CA-MRSA infections.
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Chong YP, Park SJ, Kim HS, Kim ES, Kim MN, Park KH, Kim SH, Lee SO, Choi SH, Jeong JY, Woo JH, Kim YS. Persistent Staphylococcus aureus bacteremia: a prospective analysis of risk factors, outcomes, and microbiologic and genotypic characteristics of isolates. Medicine (Baltimore) 2013; 92:98-108. [PMID: 23429353 PMCID: PMC4553980 DOI: 10.1097/md.0b013e318289ff1e] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Persistent Staphylococcus aureus bacteremia (SAB) that fails to respond to appropriate antibiotic therapy is associated with poor outcomes. Comprehensive prospective studies on risk factors and outcomes of persistent bacteremia are limited. We investigated outcomes and risk factors encompassing clinical, pharmacokinetic, microbiologic, and genotypic characteristics associated with persistent bacteremia using a case-control study nested in a prospective cohort of patients with SAB at a tertiary-care hospital from August 2008 through September 2010. We compared the clinical characteristics, management, and outcomes of patients with persistent bacteremia (≥7 d) with controls with resolving bacteremia (<3 d). To detect associations between microbiologic and genotypic characteristics of methicillin-resistant S. aureus (MRSA) isolates and persistent bacteremia, we determined the heteroresistance phenotype, SCCmec type, agr genotype and functionality, multilocus sequence typing, and presence of 41 virulence genes. Our cohort consisted of 483 patients; 76 (15.7%) had persistent bacteremia, 212 (43.5%) had resolving bacteremia. In the multivariate analysis, independent risk factors associated with persistent bacteremia were community-onset bacteremia (odds ratio [OR], 2.91; 95% confidence interval [CI], 1.24-6.87), bone and joint infection (OR, 5.26; 95% CI, 1.45-19.03), central venous catheter-related infection (OR, 3.36; 95% CI, 1.47-7.65), metastatic infection (OR, 36.22; 95% CI, 12.71-103.23), and methicillin resistance (OR, 16.99; 95% CI, 5.53-52.15). For patients with eradicable foci, delay (>3 d) in the removal of the infection focus was significantly associated with persistent bacteremia (OR, 2.18; 95% CI, 1.05-4.55). There were no significant associations of persistent bacteremia with high vancomycin minimal inhibitory concentration, vancomycin heteroresistance, and microbiologic/genotypic characteristics of MRSA isolates. However, initial vancomycin trough level <15 mg/L was an independent risk factor for persistent MRSA bacteremia (OR, 4.25; 95% CI, 1.51-11.96) in the multivariate analysis. Clinical outcomes were significantly worse for patients with persistent bacteremia. Relapse of bacteremia and attributable mortality within 12 weeks after SAB were significantly higher in patients with persistent bacteremia than in those with resolving bacteremia (9.2% [7/76] vs. 2.4% [5/212], p = 0.02 and 21.1% [16/76] vs. 9.4% [20/212], p = 0.009, respectively). In conclusion, patients with SAB should be given early aggressive treatment strategies, including early source control and maintenance of a vancomycin trough level ≥15 mg/L, to reduce the risk of persistent bacteremia.
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Affiliation(s)
- Yong Pil Chong
- From the Department of Infectious Diseases (YPC, KHP, SHK, SOL, SHC, JHW, YSK) and Department of Laboratory Medicine (MNK), Asan Medical Center, University of Ulsan College of Medicine, Center for Antimicrobial Resistance and Microbial Genetics (SJP, HSK, ESK, JYJ, YSK), Seoul, Republic of Korea
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70
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Mattis D, Spaulding A, Chuang-Smith O, Sundberg E, Schlievert P, Kranz D. Engineering a soluble high-affinity receptor domain that neutralizes staphylococcal enterotoxin C in rabbit models of disease. Protein Eng Des Sel 2013; 26:133-42. [PMID: 23161916 PMCID: PMC3542526 DOI: 10.1093/protein/gzs094] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 08/31/2012] [Accepted: 10/17/2012] [Indexed: 11/13/2022] Open
Abstract
Superantigens (SAgs) are a class of immunostimulatory exotoxins that activate large numbers of T cells, leading to overproduction of cytokines and subsequent inflammatory reactions and systemic toxicity. Staphylococcal enterotoxin C (SEC), a SAg secreted by Staphylococcus aureus, has been implicated in various illnesses including non-menstrual toxic shock syndrome (TSS) and necrotizing pneumonia. SEC has been shown to cause TSS illness in rabbits and the toxin contributes to lethality associated with methicillin-resistant S.aureus (MRSA) in a rabbit model of pneumonia. With the goal of reducing morbidity and mortality associated with SEC, a high-affinity variant of the extracellular variable domain of the T-cell receptor beta-chain for SEC (~14 kDa) was generated by directed evolution using yeast display. This protein was characterized biochemically and shown to cross-react with the homologous (65% identical) SAg staphylococcal enterotoxin B (SEB). The soluble, high-affinity T-cell receptor protein neutralized SEC and SEB in vitro and also significantly reduced the bacterial burden of an SEC-positive strain of MRSA (USA400 MW2) in an infective endocarditis model. The neutralizing agent also prevented lethality due to MW2 in a necrotizing pneumonia rabbit model. These studies characterize a soluble high-affinity neutralizing agent against SEC, which is cross-reactive with SEB, and that has potential to be used intravenously with antibiotics to manage staphylococcal diseases that involve these SAgs.
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MESH Headings
- Animals
- Anti-Bacterial Agents/administration & dosage
- Anti-Bacterial Agents/biosynthesis
- Anti-Bacterial Agents/chemistry
- Cell Line
- Cell Surface Display Techniques
- Directed Molecular Evolution
- Disease Models, Animal
- Endocarditis, Bacterial/drug therapy
- Endocarditis, Bacterial/immunology
- Endocarditis, Bacterial/microbiology
- Enterotoxins/antagonists & inhibitors
- Enterotoxins/metabolism
- Humans
- Interleukin-2/metabolism
- Lymphocyte Activation
- Methicillin-Resistant Staphylococcus aureus/immunology
- Methicillin-Resistant Staphylococcus aureus/metabolism
- Pneumonia, Staphylococcal/drug therapy
- Pneumonia, Staphylococcal/immunology
- Pneumonia, Staphylococcal/microbiology
- Protein Binding
- Protein Engineering
- Rabbits
- Receptors, Antigen, T-Cell, alpha-beta/administration & dosage
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Staphylococcal Infections/drug therapy
- Staphylococcal Infections/immunology
- Staphylococcal Infections/microbiology
- Superantigens/metabolism
- Superantigens/pharmacology
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- D.M. Mattis
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - A.R. Spaulding
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
- Present address: Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA
| | - O.N. Chuang-Smith
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - E.J. Sundberg
- Boston Biomedical Research Institute, Watertown, MA 02472, USA
- Present address: Institute of Human Virology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - P.M. Schlievert
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
- Present address: Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA
| | - D.M. Kranz
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
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Carriage of virulence factors and molecular characteristics ofStaphylococcus aureusisolates associated with bloodstream, and skin and soft tissue infections in children. Epidemiol Infect 2012; 141:2158-62. [DOI: 10.1017/s0950268812002919] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
SUMMARYWe investigated the virulence gene carriage and molecular type characteristics ofStaphylococcus aureusisolates from bloodstream infections (BSIs) and skin and soft tissue infections (SSTIs) in children. A total of 71 isolates, 16 of which were methicillin-resistantS. aureus(MRSA), were investigated by PCR for virulence-associated gene profiles, sequence type andspatype. This revealed that 76·7% and 53·7% of the SSTI and BSI isolates, respectively, exhibited simultaneous carriage of ⩾10 virulence genes. Compared to BSI isolates, carriage rates forhla,hlb,cna,clfA,seb,secandpvlgenes were significantly higher in SSTI isolates. By contrast, carriage ofeta,etbandseawas significantly higher for BSI isolates. Thirty-four sequence types (STs) and 36spatypes were identified in the 71 isolates and included 14 novel STs and four novelspatypes. ST59-MRSA-IV/V-t437 was the most common clone in the MRSA isolates. We concluded that virulence determinants are widely distributed in isolates ofS. aureusstrains from children with BSIs and SSTIs, with an unexpectedly high rate in SSTI isolates. Future profiling ofS. aureusvirulence determinants may allow the prediction of severity and outcome for children with these infections.
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Song Y, Du X, Li T, Zhu Y, Li M. Phenotypic and molecular characterization of Staphylococcus aureus recovered from different clinical specimens of inpatients at a teaching hospital in Shanghai between 2005 and 2010. J Med Microbiol 2012; 62:274-282. [PMID: 23118474 DOI: 10.1099/jmm.0.050971-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Staphylococcus aureus, including meticillin-sensitive and -resistant S. aureus (MSSA and MRSA, respectively), is associated with severe nosocomial human infections. This study aimed to investigate the molecular profile, including the dynamic changes and genotype/phenotype correlation, of S. aureus isolates recovered from different clinical specimens of inpatients with S. aureus infection over a 6-year span at a teaching hospital in Shanghai, China. Between 2005 and 2010, a random sample of 610 unique S. aureus isolates was collected from different clinical samples of inpatients with S. aureus infection for molecular and antibiotic susceptibility analysis. The results showed that, among the 610 S. aureus isolates, 20 sequence types (STs) determined by multi-locus sequence typing (primarily ST239, ST5, ST7, ST188 and ST398) and 52 spa types (primarily t002, t037, t030 and t601) were found. In total, 444 isolates (72.8 %) were MRSA and 166 (27.2 %) were MSSA. ST239-MRSA-III-spa t037 and ST5-MRSA-II-spa t002 were the predominant MRSA clones. From 2005 to 2010, spa t002, spa t037 and their corresponding STs (ST5 and ST239) were the most frequent clones among all of the S. aureus isolates and showed the most resistant phenotypes to various antibiotics. Generally, the different genotypes showed different drug resistance rates, but no isolates were resistant to vancomycin, teicoplanin or linezolid. The profiles of virulence and resistance genes differed by genetic background, with the ST239 and ST5 strains showing higher resistance rates to gentamicin, cefoxitin, ampicillin, cefazolin, erythromycin, clindamycin and levofloxacin than strains of other types. Moreover, the antiseptic resistance genes qacA/B were generally associated with these two types. The prevalence of STs was different among different clinical specimens and also changed by year. Recently (2009-2010), the distribution of predominant MRSA clones decreased, whilst the prevalence of non-predominant MSSA clones increased, especially for the isolates causing bacteraemia. Continual monitoring of clinical isolates is necessary to develop and maintain an effective strategy against S. aureus infection in the hospital setting.
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Affiliation(s)
- Yan Song
- Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Central Urumqi Road, Shanghai, PR China
| | - Xin Du
- Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Central Urumqi Road, Shanghai, PR China
| | - Tianming Li
- Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Central Urumqi Road, Shanghai, PR China
| | - Yuanjun Zhu
- Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Central Urumqi Road, Shanghai, PR China
| | - Min Li
- Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Central Urumqi Road, Shanghai, PR China
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Park KH, Lee YM, Hong HL, Kim T, Park HJ, Park SY, Moon SM, Chong YP, Kim SH, Lee SO, Choi SH, Jeong JY, Kim MN, Woo JH, Kim YS. Persistent catheter-related Staphylococcus aureus bacteremia after catheter removal and initiation of antimicrobial therapy. PLoS One 2012; 7:e46389. [PMID: 23115627 PMCID: PMC3480347 DOI: 10.1371/journal.pone.0046389] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Accepted: 08/29/2012] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Catheter-related Staphylococcus aureus bacteremia (CRSAB) occasionally persists despite catheter removal and initiation of appropriate antimicrobial therapy. The aim of this study was to determine the incidence, risk factors, and outcomes of persistent CRSAB after catheter removal and initiation of antimicrobial therapy. METHODS Consecutive patients with CRSAB were prospectively included from over a 41-month period. We compared the clinical features, 40 bacterial virulence genes, and outcomes between patients with persistent CRSAB (i.e., bacteremia for >3 days after catheter removal and initiation of appropriate antimicrobial therapy) and non-persistent CRSAB. RESULTS Among the 220 episodes of CRSAB, the catheter was kept in place in 17 (6%) and removed in 203 (94%) cases. In 43 (21%) of the 203 episodes, bacteremia persisted for >3 days after catheter removal and initiation of antimicrobial therapy. Methicillin resistance (Odds ratio [OR], 9.01; 95% confidence interval [CI], 3.05-26.61; P<0.001), non-catheter prosthetic devices (OR, 5.37; 95% CI, 1.62-17.80; P=0.006), and renal failure (OR, 3.23; 95% CI, 1.48-7.08; P=0.003) were independently associated with persistent CRSAB. Patients with persistent CRSAB were more like to experience complication than were those with non-persistent CRSAB (72% vs. 15%; P<0.001). Among all episodes due to methicillin-resistant S. aureus, persistent CRSAB isolates were associated with accessory gene regulator (agr) group II (P= .04), but presence of other bacterial virulence genes, distribution of vancomycin minimum inhibitory concentration distribution, and frequency of vancomycin heteroresistance did not differ between the groups. CONCLUSIONS In patients with CRSAB, bacteremia persisted in 21% of cases despite catheter removal and initiation of antimicrobial therapy. Methicillin resistance, renal failure, and non-catheter prosthetic devices were independent risk factors for persistent CRSAB, which was associated with a higher rate of complications.
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Affiliation(s)
- Ki-Ho Park
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Yu-Mi Lee
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Hyo-Lim Hong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Tark Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Hyun Jung Park
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - So-Youn Park
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Song Mi Moon
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Yong Pil Chong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Sung-Han Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Sang-Oh Lee
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Sang-Ho Choi
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Jin-Yong Jeong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
- Asan Institute of Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Mi-Na Kim
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Hee Woo
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Yang Soo Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
- * E-mail:
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74
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agr dysfunction and persistent methicillin-resistant Staphylococcus aureus bacteremia in patients with removed eradicable foci. Infection 2012; 41:111-9. [DOI: 10.1007/s15010-012-0348-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 09/25/2012] [Indexed: 01/25/2023]
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75
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Yu F, Li T, Huang X, Xie J, Xu Y, Tu J, Qin Z, Parsons C, Wang J, Hu L, Wang L. Virulence gene profiling and molecular characterization of hospital-acquired Staphylococcus aureus isolates associated with bloodstream infection. Diagn Microbiol Infect Dis 2012; 74:363-8. [PMID: 23021064 DOI: 10.1016/j.diagmicrobio.2012.08.015] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 08/16/2012] [Accepted: 08/18/2012] [Indexed: 11/28/2022]
Abstract
A better understanding of virulence gene profiling and molecular characterization of Staphylococcus aureus isolates associated with bloodstream infection (BSI) may provide further insights related to clinical outcomes with these infections. We analyzed 89 S. aureus isolates including 37 MRSA isolates (41.6%) recovered from 89 adult patients with BSI from 4 hospitals in Zhejiang province, eastern China. Thirty-five (94.6%) of MRSA isolates and 4 (7.7%) of methicillin-sensitive S. aureus (MSSA) isolates were resistant to multiple antimicrobials. All isolates harbored at least 2 of 22 possible virulence genes, including sdrC (92.1%), icaA (89.9%), hla (80.9%), clf (69.7%), sea (68.5%), sdrD (67.4%), hlb (67.4%), sdrE (65.2%), sei (51.7%), seg (50.6%), and cna (50.6%). Forty-four (49.4%) of all S. aureus BSI isolates, including 23 (62.2%) of MRSA isolates, harbored ≥10 of the virulence genes evaluated in this study. Sixteen (43.2%) MRSA isolates and 5 (9.6%) MSSA isolates harbored the gene encoding Panton-Valentine leukocidin (PVL). Collective genes for pvl, sdrE, sed, seg, and sei among MRSA isolates were significantly more frequent relative to MSSA isolates (P < 0.05). A total of 22 sequence types (STs), including novel ST2184, ST2199, and ST2200, and 33 spa types, including novel spa types t9530 and t9532, were identified among S. aureus BSI isolates, among which ST188 (15.7%) and ST7 (15.7%), and t091 (12.4%) and t189 (12.4%), seldom noted for Chinese isolates previously, were major STs and spa types, respectively. In contrast to previous reports, no predominant clones were found in the present study. Among the MRSA isolates, although ST239-MRSA-SCCmecIII, predominant clone in China, still represented the most common clone, it only accounted for 18.9%. However, ST188-MRSA- SCCmecIV seldom reported before accounted for 10.8%. Among the MSSA isolates, ST7-MSSA represented the most common clone (23.1%), followed by ST188-MSSA and ST630-MSSA (9.6% each). In conclusion, simultaneous carriage of multiple virulence genes and genetically considerable diversity were common among S. aureus BSI isolates. Furthermore, MRSA isolates exhibited more frequent carriage of superantigen genes and pvl relative to MSSA isolates. Taken together, there are distinctive virulence gene profiling and molecular characteristic among S. aureus isolates associated with bloodstream infection in China.
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Affiliation(s)
- Fangyou Yu
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou 325000, China
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76
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O'Hara FP, Amrine-Madsen H, Mera RM, Brown ML, Close NM, Suaya JA, Acosta CJ. Molecular characterization of Staphylococcus aureus in the United States 2004-2008 reveals the rapid expansion of USA300 among inpatients and outpatients. Microb Drug Resist 2012; 18:555-61. [PMID: 22775581 DOI: 10.1089/mdr.2012.0056] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To assess the clonal structure of Staphylococcus aureus in the United States, we performed a molecular epidemiological study of 1,055 S. aureus isolates from a nationally representative clinical isolate collection from 2004-2008. Resistant and susceptible isolates were typed with multilocus sequence typing, tested for the presence of Panton-Valentine leukocidin (PVL), and serotyped. USA300 (multilocus sequence typing clonal complex 8, PVL positive, and methicillin-resistant) was the most frequently isolated clone, expanding from 12% of all isolates in 2004 to 38% in 2006. The USA300 clone increased significantly in frequency among both outpatients and inpatients. USA300 increased in both skin and soft-tissue and invasive infection isolates. The second most frequently observed clone was clonal complex 5, PVL-negative, and methicillin-resistant, and its frequency was stable from 2004-2008. The methicillin-susceptible S. aureus in the study was polyclonal, and decreased in frequency as it was replaced by USA300.
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Affiliation(s)
- F Patrick O'Hara
- Department of Computational Biology, GlaxoSmithKline, Collegeville, Pennsylvania, USA
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77
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Immune-activating properties of Panton-Valentine leukocidin improve the outcome in a model of methicillin-resistant Staphylococcus aureus pneumonia. Infect Immun 2012; 80:2894-904. [PMID: 22665379 DOI: 10.1128/iai.06360-11] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Panton-Valentine leukocidin (PVL) is a cytotoxin expressed by many methicillin-resistant Staphylococcus aureus (MRSA) strains that cause community-acquired infections (CA-MRSA). Its role in virulence however, is controversial, with clinical data suggesting that PVL-producing strains may cause less severe disease in humans. PVL is capable of lysing human white blood cells, but at sublytic amounts, PVL can activate protective host immunity in the absence of cell damage. The concentration-dependent reactions it elicits from host cells could be the reason for seemingly contradictory results about PVL's role in virulence. We hypothesized that a key to understanding PVL's action on host cells and, possibly, outcomes from infection is the amount of toxin present, a hypothesis previously supported in studies using a low-inoculum skin infection model, where low levels of PVL augmented innate immune resistance to infection. Here, we present additional data supporting this hypothesis using a mouse model of MRSA pneumonia, wherein we found increased virulence of isogenic Δpvl strains and further confirmed PVL's capacity to activate proinflammatory responses from mouse and human neutrophils and pulmonary cells. Activation was measured as the production of phosphorylated p38 mitogen-activated protein kinase (MAPK) and proinflammatory cytokines interleukin-8 (IL-8) and KC (from human and mouse cells, respectively), as well as the release of antibacterial factors. Conversely, PVL lowered the levels of tumor necrosis factor alpha (TNF-α) produced in active pulmonary infection, while low doses induced apoptosis, suggesting that PVL also has the capacity to regulate inflammation. Our data indicate that, independent of its cytotoxic effects, PVL also plays an important and positive immunomodulatory role during MRSA infections.
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78
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Stapleton MR, Wright L, Clarke SR, Moseby H, Tarkowski A, Vendrengh M, Foster SJ. Identification of conserved antigens from staphylococcal and streptococcal pathogens. J Med Microbiol 2012; 61:766-779. [DOI: 10.1099/jmm.0.040915-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Melanie R. Stapleton
- The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Lynda Wright
- The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Simon R. Clarke
- School of Biological Sciences, AMS Building, University of Reading, Whiteknights, Reading RG6 6AJ, UK
| | - Hilde Moseby
- The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Andrej Tarkowski
- Department of Rheumatology and Inflammation Research, University of Göteborg, Guldhedsgatan 10A, S-413 46 Göteborg, Sweden
| | - Margareta Vendrengh
- Department of Rheumatology and Inflammation Research, University of Göteborg, Guldhedsgatan 10A, S-413 46 Göteborg, Sweden
| | - Simon J. Foster
- The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
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79
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Tong A, Tong SYC, Zhang Y, Lamlertthon S, Sharma-Kuinkel BK, Rude T, Ahn SH, Ruffin F, Llorens L, Tamarana G, Biek D, Critchley I, Fowler VG. Panton-Valentine leukocidin is not the primary determinant of outcome for Staphylococcus aureus skin infections: evaluation from the CANVAS studies. PLoS One 2012; 7:e37212. [PMID: 22623995 PMCID: PMC3356380 DOI: 10.1371/journal.pone.0037212] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 04/17/2012] [Indexed: 01/08/2023] Open
Abstract
The impact of Panton-Valentine leukocidin (PVL) on the severity of complicated skin and skin structure infections (cSSSI) caused by Staphylococcus aureus is controversial. We evaluated potential associations between clinical outcome and PVL presence in both methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) isolates from patients enrolled in two large, multinational phase three clinical trials assessing ceftaroline fosamil for the treatment of cSSSI (the CANVAS 1 and 2 programs). Isolates from all microbiologically evaluable patients with monomicrobial MRSA or MSSA infections (n = 473) were genotyped by PCR for pvl and underwent pulsed-field gel electrophoresis (PFGE). Genes encoding pvl were present in 266/473 (56.2%) isolates. Infections caused by pvl-positive S. aureus were associated with younger patient age, North American acquisition, and presence of major abscesses (P<0.001 for each). Cure rates of patients infected with pvl-positive and pvl-negative S. aureus were similar overall (93.6% versus 92.8%; P = 0.72), and within MRSA-infected (94.5% vs. 93.1%; P = 0.67) and MSSA-infected patients (92.2% vs. 92.7%; P = 1.00). This finding persisted after adjustment for multiple patient characteristics. Outcomes were also similar when USA300 PVL+ and non-USA300 PVL+ infections were compared. The results of this contemporary, international study suggest that pvl presence was not the primary determinant of outcome in patients with cSSSI due to either MRSA or MSSA.
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Affiliation(s)
- Amy Tong
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Steven Y. C. Tong
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
- Menzies School of Health Research, Darwin, Northern Territory, Australia
| | - Yurong Zhang
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Supaporn Lamlertthon
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
- Naresuan University, Phitsanulok, Phitsanulok Province, Thailand
| | - Batu K. Sharma-Kuinkel
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Thomas Rude
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Sun Hee Ahn
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Felicia Ruffin
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Lily Llorens
- Cerexa, Inc., Oakland, California, United States of America
| | | | - Donald Biek
- Cerexa, Inc., Oakland, California, United States of America
| | - Ian Critchley
- Cerexa, Inc., Oakland, California, United States of America
| | - Vance G. Fowler
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
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80
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Park KH, Kim ES, Kim HS, Park SJ, Bang KM, Park HJ, Park SY, Moon SM, Chong YP, Kim SH, Lee SO, Choi SH, Jeong JY, Kim MN, Woo JH, Kim YS. Comparison of the clinical features, bacterial genotypes and outcomes of patients with bacteraemia due to heteroresistant vancomycin-intermediate Staphylococcus aureus and vancomycin-susceptible S. aureus. J Antimicrob Chemother 2012; 67:1843-9. [DOI: 10.1093/jac/dks131] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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81
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Banchereau R, Jordan-Villegas A, Ardura M, Mejias A, Baldwin N, Xu H, Saye E, Rossello-Urgell J, Nguyen P, Blankenship D, Creech CB, Pascual V, Banchereau J, Chaussabel D, Ramilo O. Host immune transcriptional profiles reflect the variability in clinical disease manifestations in patients with Staphylococcus aureus infections. PLoS One 2012; 7:e34390. [PMID: 22496797 PMCID: PMC3319567 DOI: 10.1371/journal.pone.0034390] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 02/27/2012] [Indexed: 11/18/2022] Open
Abstract
Staphylococcus aureus infections are associated with diverse clinical manifestations leading to significant morbidity and mortality. To define the role of the host response in the clinical manifestations of the disease, we characterized whole blood transcriptional profiles of children hospitalized with community-acquired S. aureus infection and phenotyped the bacterial strains isolated. The overall transcriptional response to S. aureus infection was characterized by over-expression of innate immunity and hematopoiesis related genes and under-expression of genes related to adaptive immunity. We assessed individual profiles using modular fingerprints combined with the molecular distance to health (MDTH), a numerical score of transcriptional perturbation as compared to healthy controls. We observed significant heterogeneity in the host signatures and MDTH, as they were influenced by the type of clinical presentation, the extent of bacterial dissemination, and time of blood sampling in the course of the infection, but not by the bacterial isolate. System analysis approaches provide a new understanding of disease pathogenesis and the relation/interaction between host response and clinical disease manifestations.
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Affiliation(s)
- Romain Banchereau
- UT Southwestern Medical Center, Dallas, Texas, United States of America.
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82
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Patel H, Vaghasiya Y, Vyas B, Chanda S. Antibiotic-resistant Staphylococcus aureus: A Challenge to Researchers and Clinicians. ACTA ACUST UNITED AC 2012. [DOI: 10.3923/bj.2012.23.45] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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83
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Presence of genes encoding panton-valentine leukocidin is not the primary determinant of outcome in patients with hospital-acquired pneumonia due to Staphylococcus aureus. J Clin Microbiol 2012; 50:848-56. [PMID: 22205797 DOI: 10.1128/jcm.06219-11] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The impact of Panton-Valentine leukocidin (PVL) on the outcome in Staphylococcus aureus pneumonia is controversial. We genotyped S. aureus isolates from patients with hospital-acquired pneumonia (HAP) enrolled in two registrational multinational clinical trials for the genetic elements carrying pvl and 30 other virulence genes. A total of 287 isolates (173 methicillin-resistant S. aureus [MRSA] and 114 methicillin-susceptible S. aureus [MSSA] isolates) from patients from 127 centers in 34 countries for whom clinical outcomes of cure or failure were available underwent genotyping. Of these, pvl was detected by PCR and its product confirmed in 23 isolates (8.0%) (MRSA, 18/173 isolates [10.4%]; MSSA, 5/114 isolates [4.4%]). The presence of pvl was not associated with a higher risk for clinical failure (4/23 [17.4%] versus 48/264 [18.2%]; P = 1.00) or mortality. These findings persisted after adjustment for multiple potential confounding variables. No significant associations between clinical outcome and (i) presence of any of the 30 other virulence genes tested, (ii) presence of specific bacterial clone, (iii) levels of alpha-hemolysin, or (iv) delta-hemolysin production were identified. This study suggests that neither pvl presence nor in vitro level of alpha-hemolysin production is the primary determinant of outcome among patients with HAP caused by S. aureus.
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84
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Paniagua-Contreras G, Sáinz-Espuñes T, Monroy-Pérez E, Raymundo Rodríguez-Moctezuma J, Arenas-Aranda D, Negrete-Abascal E, Vaca S. Virulence Markers in <i>Staphylococcus aureus</i> Strains Isolated from Hemodialysis Catheters of Mexican Patients. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/aim.2012.24061] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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85
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Marimón JM, Villar M, García-Arenzana JM, Caba IDL, Pérez-Trallero E. Molecular characterization of Staphylococcus aureus carrying the panton-valentine leucocidin genes in northern Spain. J Infect 2012; 64:47-53. [DOI: 10.1016/j.jinf.2011.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 10/23/2011] [Accepted: 10/25/2011] [Indexed: 10/15/2022]
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86
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Xie Y, He Y, Gehring A, Hu Y, Li Q, Tu SI, Shi X. Genotypes and toxin gene profiles of Staphylococcus aureus clinical isolates from China. PLoS One 2011; 6:e28276. [PMID: 22194821 PMCID: PMC3240617 DOI: 10.1371/journal.pone.0028276] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 11/04/2011] [Indexed: 12/27/2022] Open
Abstract
A total of 108 S. aureus isolates from 16 major hospitals located in 14 different provinces in China were characterized for the profiles of 18 staphylococcal enterotoxin (SE) genes, 3 exfoliatin genes (eta, etb and etd), and the toxic shock syndrome toxin gene (tsst) by PCR. The genomic diversity of each isolate was also evaluated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and accessory gene regulator (agr) typing. Of these strains, 90.7% (98/108) harbored toxin genes, in which tsst was the most prevalent toxin gene (48.1%), followed by sea (44.4%), sek (42.6%) and seq (40.7%). The see and etb genes were not found in any of the isolates tested. Because of high-frequency transfer of toxin gene-containing mobile genetic elements between S. aureus strains, a total of 47 different toxin gene combinations were detected, including a complete egc cluster in 19 isolates, co-occurrence of sea, sek and seq in 38 strains, and sec and sel together in 11 strains. Genetic typing by PFGE grouped all the strains into 25 clusters based on 80% similarity. MLST revealed 25 sequence types (ST) which were assigned into 16 clonal complexes (CCs) including 2 new singletons. Among these, 11 new and 6 known STs were first reported in the S. aureus strains from China. Overall, the genotyping results showed high genetic diversity of the strains regardless of their geographical distributions, and no strong correlation between genetic background and toxin genotypes of the strains. For genotyping S. aureus, PFGE appears to be more discriminatory than MLST. However, toxin gene typing combined with PFGE or MLST could increase the discriminatory power of genotyping S. aureus strains.
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Affiliation(s)
- Yanping Xie
- School of Agriculture and Biology, Bor Luh Food Safety Center, Shanghai Jiao Tong University, Shanghai, China
| | - Yiping He
- Molecular Characterization of Foodborne Pathogens Research Unit, U. S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, Pennsylvania, United States of America
- * E-mail: (YH); (XS)
| | - Andrew Gehring
- Molecular Characterization of Foodborne Pathogens Research Unit, U. S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, Pennsylvania, United States of America
| | - Yu Hu
- School of Agriculture and Biology, Bor Luh Food Safety Center, Shanghai Jiao Tong University, Shanghai, China
| | - Qiongqiong Li
- School of Agriculture and Biology, Bor Luh Food Safety Center, Shanghai Jiao Tong University, Shanghai, China
| | - Shu-I Tu
- Molecular Characterization of Foodborne Pathogens Research Unit, U. S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, Pennsylvania, United States of America
| | - Xianming Shi
- School of Agriculture and Biology, Bor Luh Food Safety Center, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (YH); (XS)
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87
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Tong SYC, Chen LF, Fowler VG. Colonization, pathogenicity, host susceptibility, and therapeutics for Staphylococcus aureus: what is the clinical relevance? Semin Immunopathol 2011; 34:185-200. [PMID: 22160374 DOI: 10.1007/s00281-011-0300-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Accepted: 10/28/2011] [Indexed: 12/20/2022]
Abstract
Staphylococcus aureus is a human commensal that can also cause a broad spectrum of clinical disease. Factors associated with clinical disease are myriad and dynamic and include pathogen virulence, antimicrobial resistance, and host susceptibility. Additionally, infection control measures aimed at the environmental niches of S. aureus and therapeutic advances continue to impact upon the incidence and outcomes of staphylococcal infections. This review article focuses on the clinical relevance of advances in our understanding of staphylococcal colonization, virulence, host susceptibility, and therapeutics. Over the past decade key developments have arisen. First, rates of nosocomial methicillin-resistant S. aureus (MRSA) infections have significantly declined in many countries. Second, we have made great strides in our understanding of the molecular pathogenesis of S. aureus in general and community-associated MRSA in particular. Third, host risk factors for invasive staphylococcal infections, such as advancing age, increasing numbers of invasive medical interventions, and a growing proportion of patients with healthcare contact, remain dynamic. Finally, several new antimicrobial agents active against MRSA have become available for clinical use. Humans and S. aureus co-exist, and the dynamic interface between host, pathogen, and our attempts to influence these interactions will continue to rapidly change. Although progress has been made in the past decade, we are likely to face further surprises such as the recent waves of community-associated MRSA.
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Affiliation(s)
- Steven Y C Tong
- Division of Infectious Diseases and International Health, Duke University Medical Center, Box 102359, Durham, NC 27705, USA.
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88
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Aung MS, Urushibara N, Kawaguchiya M, Aung TS, Mya S, San T, Nwe KM, Kobayashi N. Virulence Factors and Genetic Characteristics of Methicillin-Resistant and -SusceptibleStaphylococcus aureusIsolates in Myanmar. Microb Drug Resist 2011; 17:525-35. [DOI: 10.1089/mdr.2011.0061] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Noriko Urushibara
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Mitsuyo Kawaguchiya
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | | | - San Mya
- National Health Laboratory, Yangon, Myanmar
| | - Thidar San
- National Health Laboratory, Yangon, Myanmar
| | | | - Nobumichi Kobayashi
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
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89
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Argudín MÁ, Mendoza MC, Vázquez F, Rodicio MR. Exotoxin gene backgrounds in bloodstream and wound Staphylococcus aureus isolates from geriatric patients attending a long-term care Spanish hospital. J Med Microbiol 2011; 60:1605-1612. [DOI: 10.1099/jmm.0.034611-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- M. Ángeles Argudín
- Department of Functional Biology, Laboratory of Microbiology, University of Oviedo, Oviedo, Spain
| | - M. Carmen Mendoza
- Department of Functional Biology, Laboratory of Microbiology, University of Oviedo, Oviedo, Spain
| | - Fernando Vázquez
- Monte Naranco Hospital, Oviedo, Spain
- Department of Functional Biology, Laboratory of Microbiology, University of Oviedo, Oviedo, Spain
| | - M. Rosario Rodicio
- Department of Functional Biology, Laboratory of Microbiology, University of Oviedo, Oviedo, Spain
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90
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Molecular and immunological characterization of Staphylococcus aureus in pediatric atopic dermatitis: implications for prophylaxis and clinical management. Clin Dev Immunol 2011; 2011:718708. [PMID: 22110527 PMCID: PMC3205653 DOI: 10.1155/2011/718708] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 09/01/2011] [Indexed: 11/17/2022]
Abstract
S. aureus represents a critical cofactor in atopic dermatitis (AD). In this paper, the prevalence of S. aureus infection/colonization was evaluated in 117 children as well as in their cohabitants, in order to assess the value of S. aureus characterization in predicting disease onset and severity and in providing indications for prophylaxis. Results showed that children with AD as well as their cohabitants had a significantly greater incidence of S. aureus infection/colonization as compared to controls. The genetic characterization showed a virtual identity of the bacteria strains collected at different sites of the patients with those found in the cohabitants, suggesting both a direct transmission between the nasal reservoir and the lesions in the same atopic subject and a risk for reinfection within family cohabitants. These data stress the need of preliminary laboratory assessment and posttherapy control in both AD patients and their close contacts for effective S. aureus eradication.
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91
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Nienaber JJC, Sharma Kuinkel BK, Clarke-Pearson M, Lamlertthon S, Park L, Rude TH, Barriere S, Woods CW, Chu VH, Marín M, Bukovski S, Garcia P, Corey GR, Korman T, Doco-Lecompte T, Murdoch DR, Reller LB, Fowler VG. Methicillin-susceptible Staphylococcus aureus endocarditis isolates are associated with clonal complex 30 genotype and a distinct repertoire of enterotoxins and adhesins. J Infect Dis 2011; 204:704-13. [PMID: 21844296 DOI: 10.1093/infdis/jir389] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Using multinational collections of methicillin-susceptible Staphylococcus aureus (MSSA) isolates from infective endocarditis (IE) and soft tissue infections (STIs), we sought to (1) validate the finding that S. aureus in clonal complex (CC) 30 is associated with hematogenous complications and (2) test the hypothesis that specific genetic characteristics in S. aureus are associated with infection severity. METHODS IE and STI isolates from 2 cohorts were frequency matched by geographic origin. Isolates underwent spa typing to infer CC and multiplex polymerase chain reaction for presence of virulence genes. RESULTS 114 isolate pairs were genotyped. IE isolates were more likely to be CC30 (19.5% vs 6.2%; P = .005) and to contain 3 adhesins (clfB, cna, map/eap; P < .0001 for all) and 5 enterotoxins (tst, sea, sed, see, and sei; P ≤ .005 for all). CC30 isolates were more likely to contain cna, tst, sea, see, seg, and chp (P < .05 for all). CONCLUSIONS MSSA IE isolates were significantly more likely to be CC30 and to possess a distinct repertoire of virulence genes than MSSA STI isolates from the same region. The genetic basis of this association requires further study.
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Affiliation(s)
- Juhsien J C Nienaber
- Duke University Medical Center Division of Infectious Diseases and International Health, Durham, North Carolina, USA
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92
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MINE Y, HIGUCHI W, TAIRA K, NAKASONE I, TATEYAMA M, YAMAMOTO T, UEZATO H, TAKAHASHI K. Nosocomial outbreak of multidrug-resistant USA300 methicillin-resistant Staphylococcus aureus causing severe furuncles and carbuncles in Japan. J Dermatol 2011; 38:1167-71. [DOI: 10.1111/j.1346-8138.2011.01284.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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93
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Lamy B, Laurent F, Gallon O, Doucet-Populaire F, Etienne J, Decousser JW. Antibacterial resistance, genes encoding toxins and genetic background among Staphylococcus aureus isolated from community-acquired skin and soft tissue infections in France: a national prospective survey. Eur J Clin Microbiol Infect Dis 2011; 31:1279-84. [PMID: 21997773 DOI: 10.1007/s10096-011-1441-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Accepted: 09/27/2011] [Indexed: 10/16/2022]
Abstract
The epidemiology of staphylococcal community-acquired skin and soft tissues infections (CA-SSTIs) has changed dramatically. We described prospectively the characteristics of the Staphylococcus aureus isolated from 71 non-teaching French hospitals and implicated in CA-SSTIs: antimicrobial susceptibility (mecA polymerase chain reaction [PCR], disk diffusion method), virulence factor gene (sea, tst, pvl) prevalence and genetic background (agr allele). During November 2006, 235 strains were collected (wound infection: 51%, abscess: 21%, whitlow: 8%, diabetic foot: 7%, furunculosis: 3%). sea, tst and pvl were identified in 22.1, 13.2 and 8.9% strains, respectively. agr allele 1 was the most frequently encountered genetic background, whatever the methicillin susceptibility. Among the 34 methicillin-resistant S. aureus (MRSA, 14.5% of all S. aureus), only one strain (2.9%) harboured pvl (belonging to the European ST80 clone), four (11.8%) tst (belonging to two endemic French clones) and 18 (52.9%) sea gene (mainly the Lyon clone). According to their in vitro activity, pristinamycin or trimethoprim/sulfamethoxazole could be considered as first-choice antibiotics. To date, the international pvl-positive MRSA clones have not spread in France. MRSA strains isolated from putative CA-SSTIs exhibited a genetic and phenotypic background of hospital-acquired (HA) clones. National survey should be continued, in order to monitor the emergence of virulent clones.
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Affiliation(s)
- B Lamy
- Department of Bacteriology, Hôpital Arnaud de Villeneuve, 34295, Montpellier, France
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94
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Faden H, Gill S, Lesse A. Impact of management and bacterial genomics on outcomes of Staphylococcus aureus bacteremia in children. Clin Pediatr (Phila) 2011; 50:929-35. [PMID: 21685214 DOI: 10.1177/0009922811407180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Children with Staphylococcus aureus bacteremia (SAB) generally presented with nonsevere signs and symptoms in sharp contrast to reports of adults with SAB. Despite incomplete adherence to current management guidelines, children with SAB did not experience mortality or relapse. Molecular characteristics of strains responsible for SAB in children were not significantly different than those described in adults. Improved outcomes in pediatric SAB compared with adults may most likely be attributed to less severe comorbidities in children.
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Affiliation(s)
- Howard Faden
- State University of New York at Buffalo, Buffalo, NY, USA.
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95
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Rasmussen RV, Fowler VG, Skov R, Bruun NE. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA. Future Microbiol 2011; 6:43-56. [PMID: 21162635 DOI: 10.2217/fmb.10.155] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Staphylococcus aureus bacteremia (SAB) is an urgent medical problem due to its growing frequency and its poor associated outcome. As healthcare delivery increasingly involves invasive procedures and implantable devices, the number of patients at risk for SAB and its complications is likely to grow. Compounding this problem is the growing prevalence of methicillin-resistant S. aureus (MRSA) and the dwindling efficacy of vancomycin, long the treatment of choice for this pathogen. Despite the recent availability of several new antibiotics for S. aureus, new strategies for treatment and prevention are required for this serious, common cause of human infection.
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Affiliation(s)
- Rasmus V Rasmussen
- Department of Cardiology, Copenhagen University Hospital, Gentofte, Copenhagen, Denmark
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96
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Chantry CJ, Wiedeman J, Buehring G, Peerson JM, Hayfron K, K'Aluoch O, Lonnerdal B, Israel-Ballard K, Coutsoudis A, Abrams B. Effect of flash-heat treatment on antimicrobial activity of breastmilk. Breastfeed Med 2011; 6:111-6. [PMID: 21091243 PMCID: PMC3143386 DOI: 10.1089/bfm.2010.0078] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND AND OBJECTIVES The World Health Organization recommends human immunodeficiency virus (HIV)-positive mothers in resource-poor regions heat-treat expressed breastmilk during periods of increased maternal-to-child transmission risk. Flash-heat, a "low tech" pasteurization method, inactivates HIV, but effects on milk protein bioactivity are unknown. The objectives were to measure flash-heat's effect on antimicrobial properties of lactoferrin, lysozyme, and whole milk and on the digestive resistance of lactoferrin and lysozyme. METHODS Flash-heated and unheated breastmilk aliquots from HIV-positive mothers in South Africa were "spiked" with Staphylococcus aureus and Escherichia coli and then cultured for 0, 3, and 6 hours. Lysozyme and lactoferrin activities were determined by lysis of Micrococcus luteus cells and inhibition of enteropathogenic E. coli, respectively, measured spectrophotometrically. Percentages of proteins surviving in vitro digestion, lactoferrin and lysozyme activity, and bacteriostatic activity of whole milk in heated versus unheated samples were compared. RESULTS There was no difference in rate of growth of E. coli or S. aureus in flash-heated versus unheated whole milk (p = 0.61 and p = 0.96, respectively). Mean (95% confidence interval) antibacterial activity of lactoferrin was diminished 11.1% (7.8%, 14.3%) and that of lysozyme by up to 56.6% (47.1%, 64.5%) by flash-heat. Digestion of lysozyme was unaffected (p = 0.12), but 25.4% less lactoferrin survived digestion (p < 0.0001). CONCLUSIONS In summary, flash-heat resulted in minimally decreased lactoferrin and moderately decreased lysozyme bioactivity, but bacteriostatic activity of whole milk against representative bacteria was unaffected. This suggests flash-heated breastmilk likely has a similar profile of resistance to bacterial contamination as that of unheated milk. Clinical significance of the decreased bioactivity should be tested in clinical trials.
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Affiliation(s)
- Caroline J Chantry
- Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817, USA.
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97
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Sequence diversities of serine-aspartate repeat genes among Staphylococcus aureus isolates from different hosts presumably by horizontal gene transfer. PLoS One 2011; 6:e20332. [PMID: 21625460 PMCID: PMC3098876 DOI: 10.1371/journal.pone.0020332] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 04/27/2011] [Indexed: 11/25/2022] Open
Abstract
Background Horizontal gene transfer (HGT) is recognized as one of the major forces for bacterial genome evolution. Many clinically important bacteria may acquire virulence factors and antibiotic resistance through HGT. The comparative genomic analysis has become an important tool for identifying HGT in emerging pathogens. In this study, the Serine-Aspartate Repeat (Sdr) family has been compared among different sources of Staphylococcus aureus (S. aureus) to discover sequence diversities within their genomes. Methodology/Principal Findings Four sdr genes were analyzed for 21 different S. aureus strains and 218 mastitis-associated S. aureus isolates from Canada. Comparative genomic analyses revealed that S. aureus strains from bovine mastitis (RF122 and mastitis isolates in this study), ovine mastitis (ED133), pig (ST398), chicken (ED98), and human methicillin-resistant S. aureus (MRSA) (TCH130, MRSA252, Mu3, Mu50, N315, 04-02981, JH1 and JH9) were highly associated with one another, presumably due to HGT. In addition, several types of insertion and deletion were found in sdr genes of many isolates. A new insertion sequence was found in mastitis isolates, which was presumably responsible for the HGT of sdrC gene among different strains. Moreover, the sdr genes could be used to type S. aureus. Regional difference of sdr genes distribution was also indicated among the tested S. aureus isolates. Finally, certain associations were found between sdr genes and subclinical or clinical mastitis isolates. Conclusions Certain sdr gene sequences were shared in S. aureus strains and isolates from different species presumably due to HGT. Our results also suggest that the distributional assay of virulence factors should detect the full sequences or full functional regions of these factors. The traditional assay using short conserved regions may not be accurate or credible. These findings have important implications with regard to animal husbandry practices that may inadvertently enhance the contact of human and animal bacterial pathogens.
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98
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Schaumburg F, Köck R, Friedrich AW, Soulanoudjingar S, Ngoa UA, von Eiff C, Issifou S, Kremsner PG, Herrmann M, Peters G, Becker K. Population structure of Staphylococcus aureus from remote African Babongo Pygmies. PLoS Negl Trop Dis 2011; 5:e1150. [PMID: 21572985 PMCID: PMC3091839 DOI: 10.1371/journal.pntd.0001150] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 03/09/2011] [Indexed: 12/15/2022] Open
Abstract
Background Pandemic community-acquired methicillin-resistant Staphylococcus aureus isolates (CA-MRSA) predominantly encode the Panton-Valentine leukocidin (PVL), which can be associated with severe infections. Reports from non-indigenous Sub-Saharan African populations revealed a high prevalence of PVL-positive isolates. The objective of our study was to investigate the S. aureus carriage among a remote indigenous African population and to determine the molecular characteristics of the isolates, particularly those that were PVL-positive. Methodology/Principal Findings Nasal S. aureus carriage and risk factors of colonization were systematically assessed in remote Gabonese Babongo Pygmies. Susceptibility to antibiotics, possession of toxin-encoding genes (i.e., PVL, enterotoxins, and exfoliative toxins), S. aureus protein A (spa) types and multi-locus sequence types (MLST) were determined for each isolate. The carriage rate was 33%. No MRSA was detected, 61.8% of the isolates were susceptible to penicillin. Genes encoding PVL (55.9%), enterotoxin B (20.6%), exfoliative toxin D (11.7%) and the epidermal cell differentiation inhibitor B (11.7%) were highly prevalent. Thirteen spa types were detected and were associated with 10 STs predominated by ST15, ST30, ST72, ST80, and ST88. Conclusions The high prevalence of PVL-positive isolates among Babongo Pygmies demands our attention as PVL can be associated with necrotinzing infection and may increase the risk of severe infections in remote Pygmy populations. Many S. aureus isolates from Babongo Pygmies and pandemic CA-MRSA-clones have a common genetic background. Surveillance is needed to control the development of resistance to antibiotic drugs and to assess the impact of the high prevalence of PVL in indigenous populations. Staphylococcus aureus is a bacterium that colonizes humans worldwide. The anterior nares are its main ecological niche. Carriers of S. aureus are at a higher risk of developing invasive infections. Few reports indicated a different clonal structure and profile of virulence factors in S. aureus isolates from Sub-Saharan Africa. As there are no data about isolates from remote indigenous African populations, we conducted a cross-sectional survey of S. aureus nasal carriage in Gabonese Babongo Pygmies. The isolates were characterized regarding their susceptibility to antibiotic agents, possession of virulence factors and clonal lineage. While similar carriage rates were found in populations of industrialized countries, isolates that encode the genes for the Panton-Valentine leukocidin (PVL) were clearly more prevalent than in European countries. Of interest, many methicillin-susceptible S. aureus isolates from Babongo Pygmies showed the same genetic background as pandemic methicillin-resistant S. aureus (MRSA) clones. We advocate a surveillance of S. aureus in neglected African populations to control the development of resistance to antibiotic drugs with particular respect to MRSA and to assess the impact of the high prevalence of PVL-positive isolates.
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Affiliation(s)
- Frieder Schaumburg
- Institute of Medical Microbiology, University of Münster, Münster, Germany.
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99
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Gill SR, McIntyre LM, Nelson CL, Remortel B, Rude T, Reller LB, Fowler VG. Potential associations between severity of infection and the presence of virulence-associated genes in clinical strains of Staphylococcus aureus. PLoS One 2011; 6:e18673. [PMID: 21541311 PMCID: PMC3082525 DOI: 10.1371/journal.pone.0018673] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 03/15/2011] [Indexed: 01/31/2023] Open
Abstract
Background The clinical spectrum of Staphylococcus aureus infection ranges from asymptomatic nasal carriage to osteomyelitis, infective endocarditis (IE) and death. In this study, we evaluate potential association between the presence of specific genes in a collection of prospectively characterized S. aureus clinical isolates and clinical outcome. Methodology/Principal Findings Two hundred thirty-nine S. aureus isolates (121 methicillin-resistant S. aureus [MRSA] and 118 methicillin-susceptible S. aureus [MSSA]) were screened by array comparative genomic hybridization (aCGH) to identify genes implicated in complicated infections. After adjustment for multiple tests, 226 genes were significantly associated with severity of infection. Of these 226 genes, 185 were not in the SCCmec element. Within the 185 non-SCCmec genes, 171 were less common and 14 more common in the complicated infection group. Among the 41 genes in the SCCmec element, 37 were more common and 4 were less common in the complicated group. A total of 51 of the 2014 sequences evaluated, 14 non-SCCmec and 37 SCCmec, were identified as genes of interest. Conclusions/Significance Of the 171 genes less common in complicated infections, 152 are of unknown function and may contribute to attenuation of virulence. The 14 non-SCCmec genes more common in complicated infections include bacteriophage-encoded genes such as regulatory factors and autolysins with potential roles in tissue adhesion or biofilm formation.
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Affiliation(s)
- Steven R Gill
- Department of Oral Biology, University at Buffalo, Buffalo, New York, United States of America.
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100
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Diffusion of meticillin-resistant Staphylococcus aureus USA300 strains in central Italy. Int J Antimicrob Agents 2011; 37:339-46. [DOI: 10.1016/j.ijantimicag.2010.12.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 09/23/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
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