National Institute for Research in Tuberculosis, Chennai, India.
J Acquir Immune Defic Syndr. 2013 Jul 1;63(3):331-8. doi: 10.1097/QAI.0b013e31829341af.
The Revised National TB Control Program bases diagnosis of tuberculosis (TB) on sputum smear examination and response to a course of antibiotics, whereas World Health Organization recommends early chest radiography [chest x-ray (CXR)] for HIV-infected symptomatic patients. We evaluated the utility of initial CXR in the diagnostic algorithm for symptomatic HIV-infected patients with negative sputum smears.
HIV-infected ambulatory patients with cough or fever of ≥2 weeks and 3 sputum smears negative for acid-fast bacilli were enrolled in Chennai and Pune, India, between 2007 and 2009. After a CXR and 2 sputum cultures, a course of broad-spectrum antibiotics was given and patients were reviewed after 14 days. Sensitivity, specificity, positive and negative predictive values of symptoms, CXR, and various combinations for diagnosing pulmonary tuberculosis (PTB) were determined, using sputum culture as gold standard.
Five hundred four patients (330 males; mean age: 35 years; median CD4: 175 cells per cubic millimeter) were enrolled. CXR had a sensitivity and specificity of 72% and 57%, respectively, with positive predictive value (PPV) of 21% and negative predictive value (NPV) of 93% to diagnose PTB. TB culture was positive in 49 of 235 patients (21%) with an abnormal initial CXR and 19 of 269 patients (7%) with a normal CXR (P < 0.001). Sensitivity and specificity of cough ≥2 weeks for predicting PTB was 97% and 6%, with PPV and NPV of 14% and 94%, respectively.
Although moderately sensitive, basing a diagnosis of TB on initial CXR leads to overdiagnosis. An absence of weight loss had a high NPV, whereas none of the combinations had a good PPV. A rapid and accurate diagnostic test is required for HIV-infected chest symptomatic.
修订后的国家结核病控制规划将结核病（TB）的诊断基于痰涂片检查和对一系列抗生素的反应，而世界卫生组织建议对有症状的 HIV 感染患者进行早期胸部 X 光检查（胸片）。我们评估了初始胸片在诊断无痰涂片阳性的有症状 HIV 感染患者的诊断算法中的效用。
2007 年至 2009 年，在印度钦奈和浦那招募了有咳嗽或发热≥2 周且 3 次痰涂片抗酸杆菌阴性的 HIV 感染门诊患者。在进行了 CXR 和 2 次痰培养后，给予广谱抗生素治疗，并在 14 天后对患者进行了复查。使用痰培养作为金标准，确定了症状、CXR 以及各种组合诊断肺结核（PTB）的敏感性、特异性、阳性预测值和阴性预测值。
共纳入了 504 例患者（330 例男性；平均年龄：35 岁；中位数 CD4：175 个细胞/立方毫米）。CXR 的敏感性和特异性分别为 72%和 57%，阳性预测值（PPV）为 21%，阴性预测值（NPV）为 93%，可诊断为 PTB。在初始 CXR 异常的 235 例患者中有 49 例（21%）和在 CXR 正常的 269 例患者中有 19 例（7%）TB 培养阳性（P<0.001）。咳嗽≥2 周预测 PTB 的敏感性和特异性分别为 97%和 6%，PPV 和 NPV 分别为 14%和 94%。
虽然 CXR 的敏感性适中，但基于初始 CXR 做出 TB 诊断会导致过度诊断。体重减轻缺失具有高 NPV，而任何组合都没有良好的 PPV。对于有症状的 HIV 感染者胸部症状，需要一种快速而准确的诊断测试。
