论文部分内容阅读
地点:北马拉维Karonga地区。 目的:比较在高HIV流行条件下两涂片法与三涂片法诊断肺结核的灵敏度和特异度。 设计:共对1992例可疑肺结核病人进行了检查,这些病人都有在2-7天内进行的三涂片检查结果以及至少一份标本的培养检查结果。涂片先以金胺染色并在荧光显微镜下观察,阳性者再行萋尼氏染色并在光学显微镜下观察确诊。培养检查采用L(?)wenstein-Jensen培养基接种法。标本的真阴性和真阳性根据培养检查结果而定。对两涂片法和三涂片法的诊断灵敏度、特异度以及阴性和阳性预测值进行了比较。 结果:与培养结果相比,三涂片法的灵敏度、特异度以及阳性和阴性预测值分别是70％、98％、92％和92％。头两份标本的涂片检查可以给出相似的结果。在三涂片法发现的阳性病例中,两涂片法至少可以发现其中的97％。就具有HIV检查结果的病例而言,两涂片法诊断培阳病例的灵敏度与三涂片法相同。 结论:在本研究条件下,应用荧光显微镜和光学显微镜,采用两涂片法替代三涂片法只略微降低了诊断灵敏度,但也稍微提高了诊断特异度;而且上述结果不受HIV感染状态的影响。考虑到误诊的高昂成本,提高诊断的特异度具有重要意义。在结核病控制实践中,由于采用两涂片法代替三涂片法可以节约大量时间,因此有可能使诊断的灵敏度和特异度
Location: Karonga area, Northern Malawi. PURPOSE: To compare the sensitivity and specificity of two smears and three smears in the diagnosis of tuberculosis under the prevalence of HIV. Design: A total of 1992 suspicious TB patients were examined. Both of these patients had triple-smear results within 2-7 days and at least one culture test. Smear with gold amine staining and observed under a fluorescence microscope, positive and then Niu Si staining and observed under a light microscope confirmed. Culture test using L (?) Wenstein-Jensen medium inoculation method. True negative and true positive according to the culture test results. The diagnostic sensitivity, specificity, and negative and positive predictive values for the two and three smears were compared. Results: The sensitivity, specificity, and positive and negative predictive values of the three-smear method were 70%, 98%, 92% and 92%, respectively, compared to the culture results. The first two smear tests can give similar results. In the three smear positive cases found, two smears found at least 97%. For cases with HIV test results, the sensitivity of the two smears to diagnosing cases of Pythium is the same as for the three-smear method. Conclusions: Under the conditions of this study, the use of fluorescence microscopy and optical microscopy, with the two-smear method instead of the three-smear method, reduced the diagnostic sensitivity slightly but also slightly increased the diagnostic specificity; and the above results were independent of HIV status influences. Given the high cost of misdiagnosis, it is of great importance to increase the specificity of the diagnosis. In tuberculosis control practice, because the use of two smears instead of three-smear method can save a lot of time, it is possible to make the diagnostic sensitivity and specificity