title: Clinical and molecular characteristics of invasive and noninvasive skin and soft tissue infections caused by group A Streptococcus.
abstract: The severity of skin and soft tissue infections caused by group A Streptococcus (GAS) is variable, and there are only a limited number of studies evaluating the characteristics of these infections in the literature. From May 2005 to November 2007, 73 patients with skin and soft tissue infections caused by group A Streptococcus were included in this study. Among these patients, 34 (46.6%) had invasive diseases. Diabetes mellitus, alcoholism, and hypertension were the most common underlying disorders. The overall mortality rate was 6.8%, and the elderly were predisposed to invasive infections (P < 0.001). Neutrophil percentages of ≥80, serum creatinine levels of ≥2 mg/dl, and high serum C-reactive protein levels were noted more frequently in patients with invasive infections than in patients with noninvasive infections, as were bacteremia and a high mortality rate. Of the 73 isolates, 93.2%, 97.3%, and 37% exhibited susceptibility to erythromycin, clindamycin, and tetracycline, respectively. The five most prevalent emm types were emm106 (24.7%), emm11 (12.3%), emm102 (9.6%), emm4 (8.2%), and emm12 (8.2%). Compared to other types, the emm106 type was significantly more likely to be associated with invasive diseases (P = 0.012). Dendrogram analysis showed a unique SmaI-digested pulsed-field gel electrophoresis pattern of the emm106 type that was particularly prone to cause invasive skin and soft tissue infections (P < 0.001). The results of this study suggest that isolates with the emm106 gene may be an emerging group A Streptococcus strain that causes invasive skin and soft tissue infections. Further surveillance study to understand the significance of this invasive strain is critical.
authors.affiliation: Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Jiun-Nong
authors.initials: JN
authors.lastname: Lin
authors.forename: Lin-Li
authors.initials: LL
authors.lastname: Chang
authors.forename: Chung-Hsu
authors.initials: CH
authors.lastname: Lai
authors.forename: Hsi-Hsun
authors.initials: HH
authors.lastname: Lin
authors.forename: Yen-Hsu
authors.initials: YH
authors.lastname: Chen
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000437:Alcoholism / Q000150:complications; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D048909:Diabetes Complications; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012307:Risk Factors; D012867:Skin / Q000473:pathology; D017192:Skin Diseases, Bacterial / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality / Q000473:pathology*; D018461:Soft Tissue Infections / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality / Q000473:pathology*; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality / Q000473:pathology*; D013297:Streptococcus pyogenes / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents