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Furugaito M, Arai Y, Uzawa Y, Kamisako T, Ogura K, Okamoto S, Kikuchi K. Antimicrobial Susceptibility to 27 Drugs and the Molecular Mechanisms of Macrolide, Tetracycline, and Quinolone Resistance in Gemella sp. Antibiotics (Basel) 2023; 12:1538. [PMID: 37887239 PMCID: PMC10604004 DOI: 10.3390/antibiotics12101538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/09/2023] [Accepted: 10/09/2023] [Indexed: 10/28/2023] Open
Abstract
Gemella is a catalase-negative, facultative anaerobic, Gram-positive coccus that is commensal in humans but can become opportunistic and cause severe infectious diseases, such as infective endocarditis. Few studies have tested the antimicrobial susceptibility of Gemella. We tested its antimicrobial susceptibility to 27 drugs and defined the resistant genes using PCR in 58 Gemella strains, including 52 clinical isolates and six type strains. The type strains and clinical isolates included 22 G. morbillorum, 18 G. haemolysans (GH) group (genetically indistinguishable from G. haemolysans and G. parahaemolysans), 13 G. taiwanensis, three G. sanguinis, and two G. bergeri. No strain was resistant to beta-lactams and vancomycin. In total, 6/22 (27.3%) G. morbillorum strains were erythromycin- and clindamycin-resistant ermB-positive, whereas 5/18 (27.8%) in the GH group, 6/13 (46.2%) G. taiwanensis, and 1/3 (33.3%) of the G. sanguinis strains were erythromycin-non-susceptible mefE- or mefA-positive and clindamycin-susceptible. The MIC90 of minocycline and the ratios of tetM-positive strains varied across the different species-G. morbillorum: 2 µg/mL and 27.3% (6/22); GH group: 8 µg/mL and 22.2% (4/18); G. taiwanensis: 8 µg/mL and 53.8% (7/13), respectively. Levofloxacin resistance was significantly higher in G. taiwanensis (8/13 61.5%) than in G. morbillorum (2/22 9.1%). Levofloxacin resistance was associated with a substitution at serine 83 for leucine, phenylalanine, or tyrosine in GyrA. The mechanisms of resistance to erythromycin and clindamycin differed across Gemella species. In addition, the rate of susceptibility to levofloxacin differed across Gemella sp., and the quinolone resistance mechanism was caused by mutations in GyrA alone.
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Affiliation(s)
- Michiko Furugaito
- Department of Clinical Laboratory and Biomedical Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan; (M.F.); (S.O.)
- Department of Clinical Laboratory, Kindai University Hospital, Osakasayama, Osaka 589-8511, Japan
| | - Yuko Arai
- Department of Infectious Diseases, Tokyo Women’s Medical University, Shinjuku-ku, Tokyo 162-8666, Japan; (Y.A.); (Y.U.)
| | - Yutaka Uzawa
- Department of Infectious Diseases, Tokyo Women’s Medical University, Shinjuku-ku, Tokyo 162-8666, Japan; (Y.A.); (Y.U.)
| | - Toshinori Kamisako
- Department of Clinical Laboratory Medicine, Faculty of Medicine, Kindai University, Osakasayama, Osaka 589-8511, Japan;
| | - Kohei Ogura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan;
| | - Shigefumi Okamoto
- Department of Clinical Laboratory and Biomedical Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan; (M.F.); (S.O.)
| | - Ken Kikuchi
- Department of Infectious Diseases, Tokyo Women’s Medical University, Shinjuku-ku, Tokyo 162-8666, Japan; (Y.A.); (Y.U.)
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Torres-Morales J, Mark Welch JL, Dewhirst FE, Borisy GG. Site-specialization of human oral Gemella species. J Oral Microbiol 2023; 15:2225261. [PMID: 37361319 PMCID: PMC10288933 DOI: 10.1080/20002297.2023.2225261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/28/2023] Open
Abstract
Gemella species are core members of the human oral microbiome in healthy subjects and are regarded as commensals, although they can cause opportunistic infections. Our objective was to evaluate the site-specialization of Gemella species among various habitats within the mouth by combining pangenomics and metagenomics. With pangenomics, we identified genome relationships and categorized genes as core and accessory to each species. With metagenomics, we identified the primary oral habitat of individual genomes. Our results establish that the genomes of three species, G. haemolysans, G. sanguinis and G. morbillorum, are abundant and prevalent in human mouths at different oral sites: G. haemolysans on buccal mucosa and keratinized gingiva; G. sanguinis on tongue dorsum, throat, and tonsils; and G. morbillorum in dental plaque. The gene-level basis of site-specificity was investigated by identifying genes that were core to Gemella genomes at a specific oral site but absent from other Gemella genomes. The riboflavin biosynthesis pathway was present in G. haemolysans genomes associated with buccal mucosa but absent from the rest of the genomes. Overall, metapangenomics show that Gemella species have clear ecological preferences in the oral cavity of healthy humans and provides an approach to identifying gene-level drivers of site specificity.
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Affiliation(s)
| | - Jessica L. Mark Welch
- The Forsyth Institute, Cambridge, MA, USA
- Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA, USA
| | - Floyd E. Dewhirst
- The Forsyth Institute, Cambridge, MA, USA
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
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Said M, Tirthani E. Gemella morbillorum- and Capnocytophaga sp.-Related Mycotic Thoracic Aortic Aneurysm and Mediastinal Abscess: An Unusual Case Report, a Treatment Challenge, and a Review of Literature. Cureus 2021; 13:e17728. [PMID: 34659942 PMCID: PMC8491562 DOI: 10.7759/cureus.17728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2021] [Indexed: 11/30/2022] Open
Abstract
A thoracic mycotic aortic aneurysm is an uncommon entity that can complicate mediastinal abscesses. Gemella morbillorum and Capnocytophaga sp. are oral bacteria that are very rarely encountered in this setting, especially when occurring together and with other organisms, posing a difficult treatment challenge per the available guidelines and sensitivities. We present in detail this interesting case of a multi-organism mediastinal abscess and thoracic mycotic aortic aneurysm after a previous esophagogastroduodenoscopic procedure in a 51-year-old female with known achalasia who presented with upper abdominal pain, including a successful surgical and antibiotic treatment regimen and a literature review of the involved topics.
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Affiliation(s)
- Mina Said
- Internal Medicine, Rochester Regional Health, Rochester, USA
| | - Ekta Tirthani
- Internal Medicine, Rochester Regional Health, Rochester, USA
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Toyoshima H, Fujii K, Tanigawa M, Nakamura A, Tanabe M, Tanaka H, Nakanishi Y, Sakabe S. The First Case Report of Mediastinal Abscess Caused by Gemella bergeri. Intern Med 2021; 60:1631-1635. [PMID: 33390483 PMCID: PMC8188013 DOI: 10.2169/internalmedicine.5043-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Most cases of mediastinal abscess occur as a postoperative complication of a thoracic surgical procedure or following trauma. The most common causative microorganism is Staphylococcus aureus, but it can be rarely caused by unusual microorganisms, such as Gemella species. These are relatively difficult-to-identify commensal microorganisms of the upper respiratory and gastrointestinal tracts and may cause several infections. A 66-year-old man was diagnosed with Gemella bergeri mediastinal abscess by the molecular detection of bacterial genes. He was successfully treated with penicillin antibiotic for eight weeks. To our knowledge, this is the first case report of mediastinal abscess caused by G. bergeri.
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Affiliation(s)
- Hirokazu Toyoshima
- Department of Infectious Diseases, Japanese Red Cross Ise Hospital, Japan
| | - Koji Fujii
- Department of Surgery, Japanese Red Cross Ise Hospital, Japan
| | - Motoaki Tanigawa
- Department of Respiratory Medicine, Japanese Red Cross Ise Hospital, Japan
| | - Akiko Nakamura
- Department of Infection Control, Aichi Medical University, Japan
| | - Masaki Tanabe
- Department of Infection Control and Prevention, Mie University Hospital, Japan
| | - Hiroyuki Tanaka
- Department of Infectious Diseases, Japanese Red Cross Ise Hospital, Japan
| | - Yuki Nakanishi
- Department of Infectious Diseases, Japanese Red Cross Ise Hospital, Japan
| | - Shigetoshi Sakabe
- Department of Infectious Diseases, Japanese Red Cross Ise Hospital, Japan
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Risk Factors and Patient Profile of Infective Endocarditis due to Gemella spp.. AMERICAN JOURNAL OF MEDICAL CASE REPORTS 2021; 9:103-115. [PMID: 33585676 PMCID: PMC7877815 DOI: 10.12691/ajmcr-9-2-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND The diagnosis of infective endocarditis is difficult, especially when it involves atypical organisms. Therefore, our study identified risk factors of infective endocarditis caused by rare pathogen, Gemella spp. METHODS A systematic review was conducted to investigate characteristics of endocarditis patients infected with Gemella spp. using the search term "Gemella" and "endocarditis." Case reports were gathered by searching Medline/Pubmed, Google Scholar, CINAHL, Cochrane CENTRAL, and Web of Science databases. 83 articles were selected for review. RESULTS Five species of Gemella were identified. Typical patients were males between 31 and 45 years of age. On admission, patients had fever, tachycardia, and normal blood pressure. Common clinical manifestation other than fever included fatigue and weakness, chills and sweating, and nausea, vomiting, diarrhea, and weight changes. One in four reported a history of congenital heart disease, and a recent oral cavity infection. Laboratory tests reveal anemia, leukocytosis, and elevated erythrocyte sedimentation in all age groups, elevated C-reactive protein is observed among adult and geriatric populations only. Mitral and aortic valves were most commonly infected by Gemella spp.. The most common Gemella spp.-susceptible antibiotics were penicillin, vancomycin, cephalosporin, macrolide, and aminoglycosides. However, antibiotic resistance was observed against penicillin, aminoglycoside, and fluoroquinolone. Antibiotic course of at least six weeks resulted in superior clinical improvements than durations under six weeks. Finally, one in two patients underwent valve replacement or repair, with common complications affecting the cardiovascular, neurological, and renal systems. Finally, death occurred in 1 in 8 patients, half of which occurred post-surgical procedure, and the majority occurring equal to or greater than 1 week from admission. CONCLUSION Our systematic review highlights the importance of considering rare pathogens, particularly in the presence of predisposing risk factors.
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García López E, Martín-Galiano AJ. The Versatility of Opportunistic Infections Caused by Gemella Isolates Is Supported by the Carriage of Virulence Factors From Multiple Origins. Front Microbiol 2020; 11:524. [PMID: 32296407 PMCID: PMC7136413 DOI: 10.3389/fmicb.2020.00524] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/11/2020] [Indexed: 12/29/2022] Open
Abstract
The molecular basis of the pathogenesis of the opportunistic invasive infections caused by isolates of the Gemella genus remains largely unknown. Moreover, inconsistencies in the current species assignation were detected after genome-level comparison of 16 public Gemella isolates. A literature search detected that, between the two most pathogenic species, Gemella morbillorum causes about twice the number of cases compared to Gemella haemolysans. These two species shared their mean diseases - sepsis and endocarditis - but differed in causing other syndromes. A number of well-known virulence factors were harbored by all species, such as a manganese transport/adhesin sharing 83% identity from oral endocarditis-causing streptococci. Likewise, all Gemellae carried the genes required for incorporating phosphorylcholine into their cell walls and encoded some choline-binding proteins. In contrast, other proteins were species-specific, which may justify the known epidemiological differences. G. haemolysans, but not G. morbillorum, harbor a gene cluster potentially encoding a polysaccharidic capsule. Species-specific surface determinants also included Rib and MucBP repeats, hemoglobin-binding NEAT domains, peptidases of C5a complement factor and domains that recognize extracellular matrix molecules exposed in damaged heart valves, such as collagen and fibronectin. Surface virulence determinants were associated with several taxonomically dispersed opportunistic genera of the oral microbiota, such as Granulicatella, Parvimonas, and Streptococcus, suggesting the existence of a horizontally transferrable gene reservoir in the oral environment, likely facilitated by close proximity in biofilms and ultimately linked to endocarditis. The identification of the Gemella virulence pool should be implemented in whole genome-based protocols to rationally predict the pathogenic potential in ongoing clinical infections caused by these poorly known bacterial pathogens.
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Affiliation(s)
- Ernesto García López
- Departamento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas (CSIC), Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Antonio J. Martín-Galiano
- Intrahospital Infections Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Majadahonda, Spain
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Stinson LF, Boyce MC, Payne MS, Keelan JA. The Not-so-Sterile Womb: Evidence That the Human Fetus Is Exposed to Bacteria Prior to Birth. Front Microbiol 2019; 10:1124. [PMID: 31231319 PMCID: PMC6558212 DOI: 10.3389/fmicb.2019.01124] [Citation(s) in RCA: 205] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/03/2019] [Indexed: 01/12/2023] Open
Abstract
The human microbiome includes trillions of bacteria, many of which play a vital role in host physiology. Numerous studies have now detected bacterial DNA in first-pass meconium and amniotic fluid samples, suggesting that the human microbiome may commence in utero. However, these data have remained contentious due to underlying contamination issues. Here, we have used a previously described method for reducing contamination in microbiome workflows to determine if there is a fetal bacterial microbiome beyond the level of background contamination. We recruited 50 women undergoing non-emergency cesarean section deliveries with no evidence of intra-uterine infection and collected first-pass meconium and amniotic fluid samples. Full-length 16S rRNA gene sequencing was performed using PacBio SMRT cell technology, to allow high resolution profiling of the fetal gut and amniotic fluid bacterial microbiomes. Levels of inflammatory cytokines were measured in amniotic fluid, and levels of immunomodulatory short chain fatty acids (SCFAs) were quantified in meconium. All meconium samples and most amniotic fluid samples (36/43) contained bacterial DNA. The meconium microbiome was dominated by reads that mapped to Pelomonas puraquae. Aside from this species, the meconium microbiome was remarkably heterogeneous between patients. The amniotic fluid microbiome was more diverse and contained mainly reads that mapped to typical skin commensals, including Propionibacterium acnes and Staphylococcus spp. All meconium samples contained acetate and propionate, at ratios similar to those previously reported in infants. P. puraquae reads were inversely correlated with meconium propionate levels. Amniotic fluid cytokine levels were associated with the amniotic fluid microbiome. Our results demonstrate that bacterial DNA and SCFAs are present in utero, and have the potential to influence the developing fetal immune system.
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Affiliation(s)
- Lisa F Stinson
- Division of Obstetrics and Gynaecology, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Mary C Boyce
- Centre for Integrative Metabolomics and Computational Biology, School of Science, Edith Cowan University, Perth, WA, Australia
| | - Matthew S Payne
- Division of Obstetrics and Gynaecology, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Jeffrey A Keelan
- Division of Obstetrics and Gynaecology, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
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Munson E, Carroll KC. An Update on the Novel Genera and Species and Revised Taxonomic Status of Bacterial Organisms Described in 2016 and 2017. J Clin Microbiol 2019; 57:e01181-18. [PMID: 30257907 PMCID: PMC6355528 DOI: 10.1128/jcm.01181-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Recognition and acknowledgment of novel bacterial taxonomy and nomenclature revisions can impact clinical practice, disease epidemiology, and routine clinical microbiology laboratory operations. The Journal of Clinical Microbiology (JCM) herein presents its biannual report summarizing such changes published in the years 2016 and 2017, as published and added by the International Journal of Systematic and Evolutionary Microbiology Noteworthy discussion centers around descriptions of novel Corynebacteriaceae and an anaerobic mycolic acid-producing bacterium in the suborder Corynebacterineae; revisions within the Propionibacterium, Clostridium, Borrelia, and Enterobacter genera; and a major reorganization of the family Enterobacteriaceae. JCM intends to sustain this series of reports as advancements in molecular genetics, whole-genome sequencing, and studies of the human microbiome continue to produce novel taxa and clearer understandings of bacterial relatedness.
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Affiliation(s)
- Erik Munson
- College of Health Sciences, Marquette University, Milwaukee, Wisconsin, USA
| | - Karen C Carroll
- Division of Medical Microbiology, Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Hadano Y, Kinugasa Y, Ohkusu K, Ishibashi K, Isoda M. Gemella haemolysans bacteremia in a patient with secondary peritonitis due to a duodenal ulcer perforation: A case report. IDCases 2018; 12:133-135. [PMID: 29942771 PMCID: PMC6010975 DOI: 10.1016/j.idcr.2018.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 04/26/2018] [Accepted: 04/26/2018] [Indexed: 12/15/2022] Open
Abstract
We describe a case of Gemella haemolysans septic shock in a 75-year old Japanese male with a duodenal perforation and secondary peritonitis. Blood cultures on admission were positive for Gram-positive and Gram-variable cocci, and G. haemolysans was identified using whole cell matrix-assisted laser desorpition/ionization mass spectrometry (MALDI-TOF MS), with a score value of 2.12. The 16S rRNA sequencing was difficult to use as a diagnostic test because there was more than 99% sequence homology with related bacterial strains. Based on both the biochemical profiles and whole groEL sequence, we concluded that the strain in our patient was G. haemolysans. The patient was successfully treated with a 16-day course of antimicrobials. His clinical condition improved, and no evidence of a relapse of the infection was noted. Although MALDI-TOF MS and 16S rRNA sequencing are useful for identification of the species, the basic biochemical profile is also important to identify a rare species.
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Affiliation(s)
- Yoshiro Hadano
- Department of Infectious Diseases, St. Mary's Hospital, Kurume, Japan
| | | | - Kiyofumi Ohkusu
- Department of Microbiology, Tokyo Medical University, Tokyo, Japan
| | | | - Miwako Isoda
- Department of Infectious Diseases, St. Mary's Hospital, Kurume, Japan
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Villmones HC, Haug ES, Ulvestad E, Grude N, Stenstad T, Halland A, Kommedal Ø. Species Level Description of the Human Ileal Bacterial Microbiota. Sci Rep 2018; 8:4736. [PMID: 29549283 PMCID: PMC5856834 DOI: 10.1038/s41598-018-23198-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/06/2018] [Indexed: 02/07/2023] Open
Abstract
The small bowel is responsible for most of the body’s nutritional uptake and for the development of intestinal and systemic tolerance towards microbes. Nevertheless, the human small bowel microbiota has remained poorly characterized, mainly owing to sampling difficulties. Sample collection directly from the distal ileum was performed during radical cystectomy with urinary diversion. Material from the ileal mucosa were analysed using massive parallel sequencing of the 16S rRNA gene. Samples from 27 Caucasian patients were included. In total 280 unique Operational Taxonomic Units were identified, whereof 229 could be assigned to a species or a species group. The most frequently detected bacteria belonged to the genera Streptococcus, Granulicatella, Actinomyces, Solobacterium, Rothia, Gemella and TM7(G-1). Among these, the most abundant species were typically streptococci within the mitis and sanguinis groups, Streptococcus salivarius, Rothia mucilaginosa and Actinomyces from the A. meyeri/odontolyticus group. The amounts of Proteobacteria and strict anaerobes were low. The microbiota of the distal part of the human ileum is oral-like and strikingly different from the colonic microbiota. Although our patient population is elderly and hospitalized with a high prevalence of chronic conditions, our results provide new and valuable insights into a lesser explored part of the human intestinal ecosystem.
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Affiliation(s)
| | | | - Elling Ulvestad
- Department of Microbiology, Haukeland University Hospital, 5021, Bergen, Norway.,Department of Clinical Science, University of Bergen, 5021, Bergen, Norway
| | - Nils Grude
- Department of Microbiology, Vestfold Hospital Trust, 3103, Tønsberg, Norway
| | - Tore Stenstad
- Department of Infectious Medicine, Vestfold Hospital Trust, 3103, Tønsberg, Norway
| | - Adrian Halland
- Department of Urology, Vestfold Hospital Trust, 3103, Tønsberg, Norway
| | - Øyvind Kommedal
- Department of Microbiology, Haukeland University Hospital, 5021, Bergen, Norway
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The first case report of infective endocarditis caused by Gemella taiwanensis. J Infect Chemother 2017; 23:567-571. [PMID: 28385567 DOI: 10.1016/j.jiac.2017.02.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/28/2017] [Accepted: 02/27/2017] [Indexed: 11/21/2022]
Abstract
Gemella is a facultative anaerobic Gram-positive coccus and a rare cause of infective endocarditis (IE). Gram staining may eventually misidentify the organism, which tends to easily decolorize and manifest as either Gram-negative or Gram-variable. Commercial biochemical tests are often used to identify Gemella, but the methods they employ sometimes lack accuracy. A 52-year-old woman was diagnosed with Gemella taiwanensis IE after initial identification of the pathogen as Gemella haemolysans using biochemical tests combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). She was treated successfully with penicillin, gentamicin, and mitral valve replacement. To our knowledge, this is the first case of IE confirmed by 16S rRNA gene and groEL sequencing to have been caused by G. taiwanensis. The accurate diagnosis of rare or difficult-to-identify pathogens is a major challenge for clinical microbiological laboratories. The concurrent use of molecular methods could lead to the recognition of new or different pathogens.
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Munson E, Carroll KC. What's in a Name? New Bacterial Species and Changes to Taxonomic Status from 2012 through 2015. J Clin Microbiol 2017; 55:24-42. [PMID: 27795334 PMCID: PMC5228236 DOI: 10.1128/jcm.01379-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Technological advancements in fields such as molecular genetics and the human microbiome have resulted in an unprecedented recognition of new bacterial genus/species designations by the International Journal of Systematic and Evolutionary Microbiology Knowledge of designations involving clinically significant bacterial species would benefit clinical microbiologists in the context of emerging pathogens, performance of accurate organism identification, and antimicrobial susceptibility testing. In anticipation of subsequent taxonomic changes being compiled by the Journal of Clinical Microbiology on a biannual basis, this compendium summarizes novel species and taxonomic revisions specific to bacteria derived from human clinical specimens from the calendar years 2012 through 2015.
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Affiliation(s)
- Erik Munson
- College of Health Sciences, Marquette University, Milwaukee, Wisconsin, USA
| | - Karen C Carroll
- Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Lin YT, Tsai JC, Yamamoto T, Chen HJ, Hung WC, Hsueh PR, Teng LJ. Emergence of a small colony variant of vancomycin-intermediateStaphylococcus aureusin a patient with septic arthritis during long-term treatment with daptomycin. J Antimicrob Chemother 2016; 71:1807-14. [DOI: 10.1093/jac/dkw060] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 02/15/2016] [Indexed: 11/13/2022] Open
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