Antimicrobial susceptibility and serotype of group B streptococci isolated from various

Abstract

For the purpose of analyzing the trends of group B streptococci(GBS), we investigated　the rates of isolation based on clinical specimens, sex and age, using 442 strams of GBS isolated from various clinical specimens at Kuji Prefectural Hospital in northern Japan from 1982 through 1989. All strains were serologically typed and their susceptibilities to penicillin(PCG), ampicillin(ABPC), cephaloridine(CER), cephalexin (CEX), tetracycline(TC), chloramphenicol(CP), erythromycin(EM),01eandomycin (OL)and lincomycin (LCM)were determined in terms of the minimum inhibitory concentrations of these antimicrobial agents. The results are as follows:

0f the 442 strains from clinical specimens,141 were isolated from urine(31.9%),119 by throat-swab(27.0%),66 from sputum(14.9%), and the remainning 116 from feces,otorrhea, pus and vaginal discharge. Serotype of GBS:Type W was dominant, followed by type I a and typeⅢ, type I c was isolated at a}lig}1 rate in 1986 but I b was isolated highly in 1989. Serotype of GBS by age:Type IV and I a were isolated frequently from the aged population;Type H and V were isolated from infants and schooLaged-children.Relationship between specimens and age:GBS were isolated frequently from school- aged.children by throat-swab;from the aged population, GBS was isolated from sputum and urine. The isolation rate of GBS, by age and sex:GBS isolated frequently from aged population, showed that the isolation rate of female was higher than that of male with the ratio of 6:4 . Of the 442 strains,106 (24.0%)were resistant to TC, but no correlation between resistance and serotype was observed. Resistant strains to EM, OL and LCM were predominate in typesⅢ, IV and V.Most of them were isolated from feces.