Pierre C, Olivier C, Lecossier D, Boussougant Y, Yeni P, Hance A J
INSERM Unité 82, Faculté de Médecine Xavier Bichat, Paris, France.
Am Rev Respir Dis. 1993 Feb;147(2):420-4. doi: 10.1164/ajrccm/147.2.420.
Standard microbiologic techniques were compared with a rapid diagnostic method based on the amplification by polymerase chain reaction (PCR) of a fragment of the IS6110 insertion element (present in multiple copies in the Mycobacterium tuberculosis genome) for the detection of M. tuberculosis in specimens obtained from children diagnosed as having primary tuberculosis on clinical grounds. Two (n = 7) or three (n = 15) gastric aspirates were obtained from the 22 children with primary tuberculosis. All specimens were negative for mycobacteria by acid-fast staining and culture. When DNA was purified from the clinical specimens and aliquots of each sample were amplified in duplicate, 15 of 59 (25%) specimens gave at least one positive result. Increasing beyond two the number of times that samples were tested did not appreciably improve sensitivity. Testing multiple samples from the same individual increased the diagnostic yield. Thus, when three different samples from the same subject were tested two times each, two or more positive results were obtained from 9 of 15 children with primary tuberculosis but 0 of 17 control subjects. Samples from children with symptoms, recent contact with patients with active tuberculosis, vesicular tuberculin responses, or abnormal chest radiographs were more frequently positive than those from patients whose only manifestation of tuberculosis was a positive (but not vesicular) tuberculin response. Thus, M. tuberculosis DNA can be detected by PCR in gastric aspirates of many children with primary tuberculosis, despite that specimens from these patients are negative by culture. Multiple samples must be tested to optimize the diagnostic yield.
将标准微生物学技术与基于聚合酶链反应（PCR）扩增IS6110插入元件片段（该元件在结核分枝杆菌基因组中以多拷贝形式存在）的快速诊断方法进行比较，以检测从临床上诊断为原发性结核的儿童获得的标本中的结核分枝杆菌。从22例原发性结核儿童中获取两份（n = 7）或三份（n = 15）胃抽吸物。所有标本经抗酸染色和培养，结核分枝杆菌均为阴性。当从临床标本中纯化DNA并将每个样品的等分试样进行重复扩增时，59份标本中有15份（25%）至少得到一个阳性结果。将样品检测次数增加到两次以上并没有明显提高敏感性。检测同一个体的多个样品可提高诊断率。因此，当对同一受试者的三个不同样品各检测两次时，15例原发性结核儿童中有9例获得两个或更多阳性结果，而17例对照受试者均为阴性。有症状、近期与活动性结核患者接触、出现水疱性结核菌素反应或胸部X线片异常的儿童的样品比仅结核菌素反应阳性（但不是水疱性）的结核患者的样品更常呈阳性。因此，尽管这些患者的标本培养为阴性，但通过PCR可在许多原发性结核儿童的胃抽吸物中检测到结核分枝杆菌DNA。必须检测多个样品以优化诊断率。
