Simor A E, Watt C, Low D E
Department of Microbiology, Mount Sinai Hospital; and Med-Chem Laboratories, Toronto, Ontario.
Can J Infect Dis. 1990 Spring;1(1):23-7. doi: 10.1155/1990/583209.
Verocytotoxin-producing strains of Escherichia coli, most often serotype 0157:H7, have been associated with both sporadic and epidemic diarrheal disease in Canada. In order to determine the isolation rate of E coli 0157:H7 in outpatients with diarrhea, all stool specimens submitted for culture to Med-Chem Laboratories in Metropolitan Toronto between June 1988 and September 1989 were cultured on MacConkey-Sorbitol agar in addition to standard enteric media. A total of 46 (0.3%) of 16,125 stool specimens yielded E coli 0157:H7 or verotoxin-producing E coli 0157:H(-). These isolates came from 31 patients with diarrhea; only 16 (52%) had a history of hemorrhagic colitis and one patient developed hemolytic uremic syndrome. Although MacConkey-Sorbitol agar was useful as a differential medium for detecting E coli 0157:H7, 14.5% of all specimens yielded nonsorbitol-fermenting isolates. It is not certain whether the routine use of MacConkey-Sorbitol agar is justified when isolation rates of E coli 0157:117 are very low.
产生志贺毒素的大肠杆菌菌株，最常见的血清型为O157:H7，在加拿大与散发性和流行性腹泻病都有关联。为了确定腹泻门诊患者中O157:H7大肠杆菌的分离率，1988年6月至1989年9月间提交给大多伦多地区Med-Chem实验室进行培养的所有粪便标本，除了在标准肠道培养基上培养外，还在麦康凯-山梨醇琼脂上进行培养。在16125份粪便标本中，共有46份（0.3%）培养出O157:H7大肠杆菌或产志贺毒素的O157:H(-)大肠杆菌。这些分离株来自31例腹泻患者；只有16例（52%）有出血性结肠炎病史，1例患者发展为溶血尿毒综合征。虽然麦康凯-山梨醇琼脂作为检测O157:H7大肠杆菌的鉴别培养基很有用，但所有标本中有14.5%培养出不发酵山梨醇的分离株。当O157:117大肠杆菌的分离率非常低时，常规使用麦康凯-山梨醇琼脂是否合理尚不确定。
