侵襲性及非侵襲性的Streptococcus pyogenes的危險因子分析-M protein是侵襲性的關鍵嗎?

Abstract

Background. The incidence of invasive Streptococcus pyogenes (S. pyogenes) infection had increased since 1980s, especially in western countries. Few report in epidemiologic characteristics of invasive and noninvasive S. pyogenes infection was available in Taiwan. Methods. From April 2008 through October 2008, we collected S. pyogenes strains and clinical data from 7 medical centers in Taiwan. The enrolled strains were characterized by the emm types, drug susceptbility profiles and growth rate. Logistic regression model was used to identify the risk factors associated with invasive infection, necrotizing fasciitis (NF) and streptococcal toxic shock syndrome (STSS) caused by S. pyogenes. Results. During the study periods, we collected and identified 211 strains of S. pyogenes. The most prevalent emm types were emm1 (27.1%), emm102.2 (9.5%), emm11.0 (9.5%), and emm12.0 (9.0%). The 26-valent S. pyogenes vaccine covered 60.9% (126/207) of these strains, including those from invasive cases (70.7%, 53/75) and noninvasive cases (54.1%, 73/135). The resistant rates against erythromycin and tetracycline were 15% (31/211) and 48% (102/211), respectively. Alcohol abuse, isolates with emm 1.0, older age and female were risk factors for invasive infection. Tophaceous gout, isolates with emm 1.0 and renal function impairment were risk factors for ncerotizing fasciitis. Female, isolates with emm 1.0, isolates with emm 22 were significant risk factors of STSS. Isolates obtained from cases with invasive infection possess faster growth rate than those from cases with non-invasive infection. Isolates with emm type 1.0 possess significantly faster growth rate than those with other emm types. Among the 57 isolates with emm type 1.0, 48 (84%) have the same PFGE type. Conclusion. S. pyogenes infection caused significant morbidity and mortality in Taiwan. Isolates with emm type 1 are associated with invasive infection, STSS and NF. Penicillin and otherβ-lactams tested still exerted high levels of activity against S. pyogenes isolates.