Angot P, Vergnaud M, Auzou M, Leclercq R
Service de Microbiologie, CHU C te de Nacre, Caen, France.
Eur J Clin Microbiol Infect Dis. 2000 Oct;19(10):755-8. doi: 10.1007/pl00011229.
The aim of this study was to analyze the mechanisms of macrolide resistance in French clinical isolates of Streptococcus pneumoniae. A total of 838 strains of pneumococci were isolated in 1997 in Normandy, a region of western France, by 19 microbiology laboratories. Fifty-three percent had displayed diminished susceptibility to penicillin G and 50% were resistant to erythromycin. From this collection, 92 penicillin-intermediate or -resistant and 18 penicillin-susceptible strains resistant to erythromycin were studied. The presence of erm genes coding for ribosomal methylases and of mefE-like genes responsible for macrolide efflux was screened by a multiplex polymerase chain reaction and confirmed by DNA/DNA hybridization. Of the 110 strains studied, 108 were cross-resistant to erythromycin, spiramycin and clindamycin, including 105 strains containing ermB-related genes and three strains that contained a combination of ermB- and mefE-related genes. Two strains apparently susceptible to clindamycin but resistant to spiramycin also contained ermB-related genes. No strain was resistant to erythromycin alone or contained only a mef-like gene. Therefore, resistance to erythromycin is mostly related to ribosomal methylation in this region of France.
本研究旨在分析法国临床分离的肺炎链球菌对大环内酯类抗生素耐药的机制。1997年，法国西部诺曼底地区的19个微生物实验室共分离出838株肺炎球菌。其中，53%的菌株对青霉素G的敏感性降低，50%的菌株对红霉素耐药。从这些菌株中选取了92株对青霉素中介或耐药且对红霉素耐药的菌株，以及18株对青霉素敏感且对红霉素耐药的菌株进行研究。通过多重聚合酶链反应筛选编码核糖体甲基化酶的erm基因和负责大环内酯类抗生素外排的mefE样基因的存在情况，并通过DNA/DNA杂交进行确认。在所研究的110株菌株中，108株对红霉素、螺旋霉素和克林霉素交叉耐药，其中105株含有ermB相关基因，3株同时含有ermB和mefE相关基因。另外两株对克林霉素敏感但对螺旋霉素耐药的菌株也含有ermB相关基因。没有菌株仅对红霉素耐药或仅含有mef样基因。因此，在法国的这个地区，对红霉素的耐药性主要与核糖体甲基化有关。
