title: Correlation of virulence genes to clinical manifestations and outcome in patients with Streptococcus dysgalactiae subspecies equisimilis bacteremia.
abstract: OBJECTIVE
  Streptococcus dysgalactiae subsp. equisimilis (SDSE) is increasingly recognized as a human pathogen responsible for invasive infection and streptococcal toxic shock syndrome (STSS). The pathogen possesses virulence genes that resemble those found in Streptococcus pyogenes (GAS). We analyzed the association between these specific toxic genes, clinical presentations, and outcome in patients with SDSE infections.
  
  
  METHODS
  Patients (older than 18 years) with community-acquired invasive bacteremia caused by SDSE bacteremia who were undergoing treatment at China Medical University Hospital from June 2007 to December 2010 were included in this study. Multiplex polymerase chain reaction was performed to identify virulence genes of the SDSE isolates. Demographic data, clinical presentations, and outcome in patients with SDSE infections were reviewed and analyzed.
  
  
  RESULTS
  Forty patients with 41 episodes of SDSE bacteremia were reviewed. The median age of the patients with SDSE infection was 69.7 years; 55% were female and 78% had underlying diseases. Malignancy (13, 33%) and diabetes mellitus (13, 33%) were the most common comorbidities. The 30-day mortality rate was 12%. Compared with the survivors, the non-survivors had a higher rate of diabetes mellitus (80% vs. 26%), liver cirrhosis (60% vs.11%), shock (60% vs.17%), STSS (60% vs. 8%), and a high Pittsburgh bacteremia score >4 (40% vs. 6%). Most isolates had scpA, ska, saga, and slo genes, whereas speC, speG, speH, speI, speK, smez, and ssa genes were not detected. speA gene was identified only in one patient with STSS (1/6, 17%). All isolates were susceptible to penicillin, cefotaxime, levofloxacin, moxifloxacin, vancomycin, and linezolid.
  
  
  CONCLUSIONS
  In invasive SDSE infections, most isolates carry putative virulence genes, such as scpA, ska, saga, and slo. Clinical SDSE isolates in Taiwan remain susceptible to penicillin cefotaxime, and levofloxacin.
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Chia-Ta
authors.initials: CT
authors.lastname: Tsai
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.
authors.forename: Chih-Yu
authors.initials: CY
authors.lastname: Chi
authors.affiliation: Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Cheng-Mao
authors.initials: CM
authors.lastname: Ho
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Po-Chang
authors.initials: PC
authors.lastname: Lin
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Chia-Hui
authors.initials: CH
authors.lastname: Chou
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Jen-Hsien
authors.initials: JH
authors.lastname: Wang
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Jui-Hsing
authors.initials: JH
authors.lastname: Wang
authors.affiliation: Department of Pediatrics, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Hsiao-Chuan
authors.initials: HC
authors.lastname: Lin
authors.affiliation: Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Ni
authors.initials: N
authors.lastname: Tien
authors.affiliation: Division of Infectious Diseases, Department of Health, Chang-Hua Hospital, Chang-Hua, Taiwan.
authors.forename: Kuo-Hsi
authors.initials: KH
authors.lastname: Lin
authors.affiliation: Division of Infectious Disease, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan. Electronic address: D7905@mail.cmuh.org.tw.
authors.forename: Mao-Wang
authors.initials: MW
authors.lastname: Ho
authors.affiliation: Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Kweishan, Taoyuan, Taiwan. Electronic address: janglu45@gmail.com.
authors.forename: Jang-Jih
authors.initials: JJ
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016470:Bacteremia / Q000382:microbiology* / Q000473:pathology*; D002681:China; D017714:Community-Acquired Infections / Q000382:microbiology / Q000473:pathology; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000382:microbiology* / Q000473:pathology*; D013291:Streptococcus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D013624:Taiwan; D016896:Treatment Outcome; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D037521:Virulence Factors
keywords: Phoenix Automated Microbiology System; Streptococcal toxic shock syndrome; Streptococcus dysgalactiae subsp. dysgalactiae; Streptococcus dysgalactiae subsp. equisimilis; Superantigen