Murray P R, Wold A D, Hall M M, Washington J A
J Pediatr. 1976 Oct;89(4):576-9. doi: 10.1016/s0022-3476(76)80389-7.
The detection of group A beta-hemolytic streptococci by bacitracin susceptibility was examined, with the presumptive identification on primary blood agar plates compared with that on pure subcultured plates. A total of 638 group A streptococcus isolates was recovered from 4,632 throat swab specimens. Only about half of these isolates were identifiable on the primary plate, compared with 96% identifiable on pure subcultured plates. The unreliable results with bacitracin disk testing on primary plates were due to (1) too few colonies present in the vicinity of the disk or (2) colonies overgrown by oropharyngeal flora.
通过杆菌肽敏感性检测A组β溶血性链球菌，并将在初代血琼脂平板上的初步鉴定结果与在纯传代培养平板上的结果进行比较。从4632份咽拭子标本中总共分离出638株A组链球菌。在初代平板上，只有约一半的分离株可被鉴定，而在纯传代培养平板上这一比例为96%。在初代平板上进行杆菌肽纸片试验结果不可靠的原因是：（1）纸片附近菌落数量过少；（2）菌落被口咽菌群过度生长。
