Presumptive identification and antibiotic susceptibility of group B streptococci.
The comparative performance of three presumptive identification tests for group B haemolytic streptococci was investigated, using 371 different clinical isolates of group B streptococci. Hippurate was hydrolysed by 96-1%, the CAMP reaction was positive in 95-0%, and pigment was produced by 97-3%. A combination of any two tests would have detected over 99-8%. On bile esculin agar 99-0% were able to grow, but non hydrolysed esculin; 5-1% were susceptible to bacitracin. The minimum inhibitory concentrations of five antibiotics for 279 group B streptococci were determined. All were susceptible to penicillin G, ampicillin, cephalothin, and erythromycin, while 80% were resistant to tetracycline. The MIC distributions were independent of the results of any identification test.
D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001414:Bacitracin / Q000494:pharmacology; D002512:Cephalothin / Q000494:pharmacology; D004912:Erythrocytes / Q000378:metabolism; D004917:Erythromycin / Q000494:pharmacology; D004929:Esculin / Q000378:metabolism; D006461:Hemolysis; D006626:Hippurates / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D008826:Microbial Sensitivity Tests; D010400:Penicillin G / Q000494:pharmacology; D010858:Pigmentation; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000302:isolation & purification* / Q000378:metabolism; D013752:Tetracycline / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D006626:Hippurates; D001414:Bacitracin; D004929:Esculin; D004917:Erythromycin; D000667:Ampicillin; D013752:Tetracycline; D010400:Penicillin G; D002512:Cephalothin