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Xie O, Davies MR, Tong SYC. Streptococcus dysgalactiae subsp. equisimilis infection and its intersection with Streptococcus pyogenes. Clin Microbiol Rev 2024:e0017523. [PMID: 38856686 DOI: 10.1128/cmr.00175-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024] Open
Abstract
SUMMARYStreptococcus dysgalactiae subsp. equisimilis (SDSE) is an increasingly recognized cause of disease in humans. Disease manifestations range from non-invasive superficial skin and soft tissue infections to life-threatening streptococcal toxic shock syndrome and necrotizing fasciitis. Invasive disease is usually associated with co-morbidities, immunosuppression, and advancing age. The crude incidence of invasive disease approaches that of the closely related pathogen, Streptococcus pyogenes. Genomic epidemiology using whole-genome sequencing has revealed important insights into global SDSE population dynamics including emerging lineages and spread of anti-microbial resistance. It has also complemented observations of overlapping pathobiology between SDSE and S. pyogenes, including shared virulence factors and mobile gene content, potentially underlying shared pathogen phenotypes. This review provides an overview of the clinical and genomic epidemiology, disease manifestations, treatment, and virulence determinants of human infections with SDSE with a particular focus on its overlap with S. pyogenes. In doing so, we highlight the importance of understanding the overlap of SDSE and S. pyogenes to inform surveillance and disease control strategies.
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Affiliation(s)
- Ouli Xie
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Monash Infectious Diseases, Monash Health, Melbourne, Australia
| | - Mark R Davies
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Steven Y C Tong
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Victorian Infectious Disease Service, The Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
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Nigussie D, Makonnen E, Legesse BA, Fekadu A, Davey G. Antimicrobial susceptibility of bacteria isolated from the infected wounds of patients with lymphoedema in East Wollega, Ethiopia. Trans R Soc Trop Med Hyg 2020; 114:962-973. [PMID: 33247921 PMCID: PMC7738659 DOI: 10.1093/trstmh/traa143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/23/2020] [Accepted: 11/07/2020] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Lymphoedema is caused by dysfunction of the lymphatic system resulting in accumulation of high-protein content fluid in the interstitial space. To date, the bacteria associated with wound infections of patients with lower limb lymphoedema in Ethiopia have not been studied. This study identified pathogenic bacteria involved in wound infection and assessed antimicrobial susceptibility patterns in patients with lymphoedema in Ethiopia. METHODS Swab samples were collected from the wounds of patients with lymphoedema and cultured using standard microbiological techniques. Micro-organisms were identified by colony morphology followed by identification and antimicrobial susceptibility testing using the automated VITEK 2 COMPACT Microbial Detection System. RESULTS Swabs were collected from 103 patients and 84 were culture positive: 44 (52.4%) culture-positive samples showed polymicrobial growth and 40 (47.6%) grew single bacterial isolates. In total, 134 isolates were obtained, of which 26 gram-negative and 12 gram-positive bacterial species were identified. A total of 28/63 (44.4%) gram-negative isolates and 3/57 (5.3%) gram-positive isolates were multiple drug resistant. There was no resistance to ciprofloxacin, moxifloxacin or gentamycin among gram-negative or gram-positive bacteria. CONCLUSION In this study, many infections were polymicrobial and showed multiple drug resistance. Fluoroquinolones and gentamycin, however, seemed to be effective against bacterial wound infection in this setting.
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Affiliation(s)
- Dereje Nigussie
- Center for Innovative Drug Development and Therapeutic Trials for Africa (CDT-Africa), College of Health Sciences, Addis Ababa University, PO Box 9086, Addis Ababa, Ethiopia
- Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX, UK
| | - Eyasu Makonnen
- Center for Innovative Drug Development and Therapeutic Trials for Africa (CDT-Africa), College of Health Sciences, Addis Ababa University, PO Box 9086, Addis Ababa, Ethiopia
- Department of Pharmacology and Clinical Pharmacy, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Belete Adefris Legesse
- Center for Innovative Drug Development and Therapeutic Trials for Africa (CDT-Africa), College of Health Sciences, Addis Ababa University, PO Box 9086, Addis Ababa, Ethiopia
| | - Abebaw Fekadu
- Center for Innovative Drug Development and Therapeutic Trials for Africa (CDT-Africa), College of Health Sciences, Addis Ababa University, PO Box 9086, Addis Ababa, Ethiopia
- Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX, UK
| | - Gail Davey
- Centre for Global Health Research, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX, UK
- School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
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Systems and Precision Medicine in Necrotizing Soft Tissue Infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1294:187-207. [PMID: 33079370 DOI: 10.1007/978-3-030-57616-5_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Necrotizing soft tissue infections (NSTI) are multifactorial and characterized by dysfunctional, time dependent, highly varying hyper- to hypo-inflammatory host responses contributing to disease severity. Furthermore, host-pathogen interactions are diverse and difficult to identify and characterize, due to the many different disease endotypes. There is a need for both refined bedside diagnostics as well as novel targeted treatment options to improve outcome in NSTI. In order to achieve clinically relevant results and to guide preclinical and clinical research the vast amount of fragmented clinical and experimental datasets, which often include omics data at different levels (transcriptomics, proteomics, metabolomics, etc.), need to be organized, harmonized, integrated, and analyzed taking into account the Big Data nature of these datasets. In this chapter, we address these matters from a systems perspective and yet personalized approach. The chapter provides an overview on the increasingly more frequent use of Big Data and Artificial Intelligence (AI) to aggregate and generate knowledge from burgeoning clinical and biochemical information, addresses the challenges to manage this information, and summarizes current efforts to develop robust computer-aided clinical decision support systems so to tackle the serious challenges in NSTI diagnosis, stratification, and optimized tailored therapy.
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Pulido-Cejudo A, Guzmán-Gutierrez M, Jalife-Montaño A, Ortiz-Covarrubias A, Martínez-Ordaz JL, Noyola-Villalobos HF, Hurtado-López LM. Management of acute bacterial skin and skin structure infections with a focus on patients at high risk of treatment failure. Ther Adv Infect Dis 2017; 4:143-161. [PMID: 28959445 DOI: 10.1177/2049936117723228] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Over the last 25 years, the terminology of skin and soft tissue infections, as well as their classification for optimal management of patients, has changed. The so-called and recently introduced term 'acute bacterial skin and skin structure infections' (ABSSSIs), a cluster of fairly common types of infection, including abscesses, cellulitis, and wound infections, require an immediate effective antibacterial treatment as part of a timely and cautious management. The extreme level of resistance globally to many antibiotic drugs in the prevalent causative pathogens, the presence of risk factors of treatment failure, and the high epidemic of comorbidities (e.g. diabetes and obesity) make the appropriate selection of the antibiotic for physicians highly challenging. The selection of antibiotics is primarily empirical for ABSSSI patients which subsequently can be adjusted based on culture results, although rarely available in outpatient management. There is substantial evidence suggesting that inappropriate antibiotic treatment is given to approximately 20-25% of patients, potentially prolonging their hospital stay and increasing the risk of morbidity and mortality. The current review paper discusses the concerns related to the management of ABSSSI and the patient types who are most vulnerable to poor outcomes. It also highlights the key management time-points that treating physicians and surgeons must be aware of in order to achieve clinical success and to discharge patients from the hospital as early as possible.
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Affiliation(s)
| | | | - Abel Jalife-Montaño
- Department of General Surgery, Hospital General de México, México City, México
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Traverso F, Blanco A, Villalón P, Beratz N, Sáez Nieto JA, Lopardo H. Molecular characterization of invasive Streptococcus dysgalactiae subsp. equisimilis. Multicenter study: Argentina 2011-2012. Rev Argent Microbiol 2016; 48:279-289. [PMID: 28341023 DOI: 10.1016/j.ram.2016.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/01/2016] [Accepted: 07/31/2016] [Indexed: 11/27/2022] Open
Abstract
Streptococcus dysgalactiae subsp. equisimilis (SDSE) has virulence factors similar to those of Streptococcus pyogenes. Therefore, it causes pharyngitis and severe infections indistinguishable from those caused by the classic pathogen. The objectives of this study were: to know the prevalence of SDSE invasive infections in Argentina, to study the genetic diversity, to determine the presence of virulence genes, to study antibiotic susceptibility and to detect antibiotic resistance genes. Conventional methods of identification were used. Antibiotic susceptibility was determined by the disk diffusion and the agar dilution methods and the E-test. Twenty eight centers from 16 Argentinean cities participated in the study. Twenty three isolates (16 group G and 7 group C) were obtained between July 1 2011 and June 30 2012. Two adult patients died (8.7%). Most of the isolates were recovered from blood (60.9%). All isolates carried speJ and ssa genes. stG62647, stG653 and stG840 were the most frequent emm types. Nineteen different PFGE patterns were detected. All isolates were susceptible to penicillin and levofloxacin, 6 (26.1%) showed resistance or reduced susceptibility to erythromycin [1 mef(A), 3 erm(TR), 1 mef(A)+erm(TR) and 1 erm(TR)+erm(B)] and 7 (30.4%) were resistant or exhibited reduced susceptibility to tetracycline [2 tet(M), 5 tet(M)+tet(O)]. The prevalence in Argentina was of at least 23 invasive infections by SDSE. A wide genetic diversity was observed. All isolates carried speJ and ssa genes. Similarly to other studies, macrolide resistance (26.1%) was mainly associated to the MLSB phenotype.
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Affiliation(s)
- Fernando Traverso
- Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina; Nueva Clínica Chacabuco, Tandil, Buenos Aires, Argentina; Servicio de Neumotisiología, Tandil, Buenos Aires, Argentina.
| | - Alejandra Blanco
- Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina
| | - Pilar Villalón
- Centro Nacional de Microbiología ISCIII, Majadahonda, Madrid, Spain
| | - Noelia Beratz
- Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina
| | | | - Horacio Lopardo
- Servicio de Microbiología, Hospital de Pediatría Prof. Dr. Juan P Garrahan, Buenos Aires, Argentina
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Midha M, Rosenthal ME. Group G streptococcal myositis in a patient with myeloproliferative neoplasm. IDCases 2016; 5:54-6. [PMID: 27500083 PMCID: PMC4971150 DOI: 10.1016/j.idcr.2016.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 07/12/2016] [Accepted: 07/12/2016] [Indexed: 12/05/2022] Open
Abstract
While many cases of streptococcal infection are due to Lancefield groups A and B, there has been a rise in reported cases of infections due to group G streptococcus. We present a case of an individual with a hematologic malignancy who developed myositis secondary to group G streptococcus, with no clearly identifiable source of infection. The patient was managed with antibiotic therapy rather than surgical intervention due to high surgical risk related to severe thrombocytopenia. Targeted antibiotics initiated early in the course of disease may prevent the need for surgical intervention. Early diagnosis and treatment are critical to avoid the high morbidity and mortality of life-threatening infections caused by group G streptococcus.
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Affiliation(s)
- Monica Midha
- Department of Medicine, Jersey Shore University Medical Center, 1945 State Route 33, Neptune, NJ, 07753, United States
| | - Marnie E Rosenthal
- Division of Infectious Diseases, Jersey Shore University Medical Center, 1945 State Route 33, Neptune, NJ, 07753, United States
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Siemens N, Kittang BR, Chakrakodi B, Oppegaard O, Johansson L, Bruun T, Mylvaganam H, Svensson M, Skrede S, Norrby-Teglund A. Increased cytotoxicity and streptolysin O activity in group G streptococcal strains causing invasive tissue infections. Sci Rep 2015; 5:16945. [PMID: 26601609 PMCID: PMC4658506 DOI: 10.1038/srep16945] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 10/22/2015] [Indexed: 11/09/2022] Open
Abstract
Streptococcus dysgalactiae subsp. equisimilis (SDSE) has emerged as an important cause of severe skin and soft tissue infections, but little is known of the pathogenic mechanisms underlying tissue pathology. Patient samples and a collection of invasive and non-invasive group G SDSE strains (n = 69) were analyzed with respect to virulence factor expression and cytotoxic or inflammatory effects on human cells and 3D skin tissue models. SDSE strains efficiently infected the 3D-skin model and severe tissue pathology, inflammatory responses and altered production of host structural framework proteins associated with epithelial barrier integrity were evident already at 8 hours post-infection. Invasive strains were significantly more cytotoxic towards keratinocytes and expressed higher Streptokinase and Streptolysin O (SLO) activities, as compared to non-invasive strains. The opposite was true for Streptolysin S (SLS). Fractionation and proteomic analysis of the cytotoxic fractions implicated SLO as a factor likely contributing to the keratinocyte cytotoxicity and tissue pathology. Analyses of patient tissue biopsies revealed massive bacterial load, high expression of slo, as well as immune cell infiltration and pro-inflammatory markers. Our findings suggest the contribution of SLO to epithelial cytotoxicity and tissue pathology in SDSE tissue infections.
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Affiliation(s)
- Nikolai Siemens
- Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Bård R Kittang
- Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Bhavya Chakrakodi
- Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Oddvar Oppegaard
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Linda Johansson
- Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Trond Bruun
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Haima Mylvaganam
- Department of Microbiology, Haukeland University Hospital, Bergen, Norway
| | | | - Mattias Svensson
- Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Steiner Skrede
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Medicine, Haukeland University Hospital, Bergen, Norway
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Komatsu Y, Okazaki A, Hirahara K, Araki K, Shiohara T. Differences in clinical features and outcomes between group A and group G Streptococcus -induced cellulitis. Dermatology 2015; 230:244-9. [PMID: 25678161 DOI: 10.1159/000371813] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 12/21/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Streptococci are the main causative agents of cellulitis, and group G Streptococcus (GGS) shares many important virulent factors with group A Streptococcus (GAS). The difference in the clinical features of GAS- and GGS-induced cellulitis, however, has not been thoroughly characterized. OBJECTIVE Our aim was to recognize the differences in the clinical manifestations and outcomes of lower limb cellulitis caused by GAS and GGS. METHODS We retrospectively analyzed a total of 29 patients diagnosed with GAS- or GGS-induced lower limb cellulitis during the period from January 2008 to September 2013. RESULTS While the clinical manifestations of GAS-induced cellulitis were likely to be uniform, those of GGS-induced cellulitis were variable, depending on the predisposing factors. GGS-induced cellulitis occurred more frequently in older person who had chronic underlying illness. CONCLUSION We identified clinical predisposing factors that can predict the clinical course and outcomes of GGS-induced cellulitis.
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Affiliation(s)
- Yurie Komatsu
- Department of Dermatology, Kyorin University School of Medicine, Mitaka, Japan
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Merriman JA, Schlievert PM. Are we close to a vaccination against Staphylococcus aureus? Future Microbiol 2014; 9:717-20. [DOI: 10.2217/fmb.14.40] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Joseph A Merriman
- Department of Microbiology, Carver College of Medicine, University of Iowa, 51 Newton Road, Iowa City, Iowa, 52242 USA
| | - Patrick M Schlievert
- Department of Microbiology, Carver College of Medicine, University of Iowa, 51 Newton Road, Iowa City, Iowa, 52242 USA
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Abstract
SUMMARY This review begins with a discussion of the large family of Staphylococcus aureus and beta-hemolytic streptococcal pyrogenic toxin T lymphocyte superantigens from structural and immunobiological perspectives. With this as background, the review then discusses the major known and possible human disease associations with superantigens, including associations with toxic shock syndromes, atopic dermatitis, pneumonia, infective endocarditis, and autoimmune sequelae to streptococcal illnesses. Finally, the review addresses current and possible novel strategies to prevent superantigen production and passive and active immunization strategies.
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Iwata K, Arinuma Y, Nakayama H, Nogi S, Futami H, Takaoka H, Hashimoto A, Shimada K, Komiya A, Matsui T, Saito I, Tohma S. An autopsy case of necrotizing fasciitis with rapidly progressive purpura caused by hemolytic streptococcal infection in a patient with rheumatoid arthritis. Mod Rheumatol 2014. [DOI: 10.3109/s10165-011-0454-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Bruun T, Kittang B, de Hoog B, Aardal S, Flaatten H, Langeland N, Mylvaganam H, Vindenes H, Skrede S. Necrotizing soft tissue infections caused by Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis of groups C and G in western Norway. Clin Microbiol Infect 2013; 19:E545-50. [DOI: 10.1111/1469-0691.12276] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 05/07/2013] [Accepted: 05/07/2013] [Indexed: 01/22/2023]
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Necrotizing fasciitis in a pediatric patient caused by lancefield group g streptococcus: case report and brief review of the literature. Case Rep Med 2011; 2011:671365. [PMID: 22242030 PMCID: PMC3254238 DOI: 10.1155/2011/671365] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/27/2011] [Accepted: 10/11/2011] [Indexed: 11/18/2022] Open
Abstract
We report a case of necrotizing fasciitis with an accompanying toxic shock syndrome caused by Group G Streptococcus in a pediatric patient with a lymphatic malformation. Pediatricians need to be aware of the possibility of such infections, especially in those with vascular/lymphatic malformations, as early treatment is critical for survival.
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Iwata K, Arinuma Y, Nakayama H, Nogi S, Futami H, Takaoka H, Hashimoto A, Shimada K, Komiya A, Matsui T, Saito I, Tohma S. An autopsy case of necrotizing fasciitis with rapidly progressive purpura caused by hemolytic streptococcal infection in a patient with rheumatoid arthritis. Mod Rheumatol 2011; 21:669-72. [PMID: 21499909 DOI: 10.1007/s10165-011-0454-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 03/25/2011] [Indexed: 10/18/2022]
Abstract
A 77-year-old woman with rheumatoid arthritis was admitted as an emergency because of pain in the right leg with purpura. She was diagnosed with severe cellulitis and sepsis and started on intravenous antibiotics; however, the lesion rapidly extended to the proximal thigh and she died only 38 h after the onset of the first symptom. Autopsy and tissue culture revealed necrotizing fasciitis caused by Streptococcus dysgalactiae subspecies equisimilis. Physicians should consider that necrotizing fasciitis may be present when soft-tissue disorder is suspected in patients receiving corticosteroid therapy, which is associated with tissue fragility and immunosuppression.
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Affiliation(s)
- Kanako Iwata
- Department of Rheumatology, Sagamihara National Hospital, National Hospital Organization, 18-1 Sakuradai, Minami-ku, Sagamihara, Kanagawa 252-0392, Japan
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Takahashi T, Ubukata K, Watanabe H. Invasive infection caused by Streptococcus dysgalactiae subsp. equisimilis: characteristics of strains and clinical features. J Infect Chemother 2010; 17:1-10. [PMID: 20607346 DOI: 10.1007/s10156-010-0084-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Indexed: 10/19/2022]
Abstract
Among clinically isolated β-hemolytic streptococci, Streptococcus pyogenes and S. agalactiae were considered the main pathogens in humans until recently. In 1996, S. dysgalactiae subsp. equisimilis (SDSE) was proposed as a novel taxon among human-derived streptococcal isolates. SDSE has Lancefield group C or G antigens, exhibits strong β-hemolysis, and exerts streptokinase activity upon human plasminogen and proteolytic activity upon human fibrin. Similarly to group A streptococci, SDSE possesses virulence factors including M protein, streptolysin O, streptolysin S, streptokinase, hyaluronidase, C5a peptidase, and others. SDSE may exist among the normal flora of the skin, oropharynx, and gastrointestinal and genitourinary tracts. In the twenty-first century, invasive SDSE infection (i.e., cellulitis, urosepsis, and pneumonia) leading to various disseminated diseases is being diagnosed increasingly in Japan, elsewhere in Asia, in Europe, and in America. Particularly, among elderly patients, these invasive diseases are encountered increasingly in Japanese hospital emergency departments. Analysis of the part of the emm gene encoding the amino acid sequence at the N-terminal end of the M protein is used to determine the molecular epidemiology of SDSE. The distribution of emm types from patients with invasive or noninvasive infections differs between surveillance results from different countries. In this review, we summarize the characteristics of phenotypes and virulence factors in SDSE strains; the review also focuses on emerging SDSE infectious disease and future vaccination research.
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Affiliation(s)
- Takashi Takahashi
- Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.
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