Diagnostic value of T-cell spot test for tuberculosis infection in patients with pulmonary tuberculosis and diabetes mellitus

Abstract

Objective To explore the diagnostic value of T-cell spot test for tuberculosis infection (T-SPOT.TB)in patients with pulmonary tuberculosis (PTB) and diabetes mellitus (DM).

Methods Totally 106 patients with DM complicated with suspected PTB were selected from respiratory department of Hebei Chest Hospitalfrom February 2017 to December 2018. Among them, 62 patients with PTB complicated with DM were diagnosed as the observation group and 44 patients with DM alone as the control group. T-SPOT.TB, tuberculin (PPD) test and sputum acid-fast bacilli (AFB) smear were performed in all patients, at the same time, the results of T-SPOT.TB test in the diagnosis of PTB combined with DM under different blood sugar control conditions were compared.

Results The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of sputum smear AFB in the diagnosis of PTB with DM were respectively 27.42% (17/62), 95.45% (42/44), 89.47% (17/19), 48.28% (42/87) and 55.66% (59/106); but the diagnostic results of PPD test were respectively 56.45% (35/62), 84.09% (37/44), 83.33% (35/42), 57.81% (37/64) and 67.92% (59/106), and the diagnostic results of T-SPOT.TB were respectively 95.16% (59/62), 93.18% (41/44), 95.16% (59/62), 93.18% (41/44) and 94.34% (100/106). Among them, the sensitivity, negative predictive value and accuracy of T-SPOT.TB diagnosis were significantly higher than those of sputum AFB smear and PPD test ( P<0.05). There were no significant difference in the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of T-SPOT.TB test in patients with good blood glucose control and poor blood glucose control ( P>0.05).

Conclusion T-SPOT.TB detection has higher sensitivity and clinical application value in the clinical diagnosis of PTB combined with DM.

Abstract

摘要： 目的 探讨结核感染T细胞斑点试验 (T-SPOT.TB) 在肺结核 (PTB) 合并糖尿病 (DM) 患者中的诊断价值。 方法 选取2017年2月—2018年12月河北省胸科医院结核内科收治的106例DM并发可疑PTB患者, 其中确诊为PTB 合并DM患者62例, 设为观察组; 单纯DM患者44例, 设为对照组。对所有受试者进行T-SPOT.TB、结核菌素 (PPD) 试 验及痰抗酸杆菌 (AFB) 涂片检测, 同时对比不同血糖控制情况下T-SPOT.TB检测诊断PTB合并DM的结果。 结果痰 涂片AFB诊断PTB合并DM的灵敏度、特异度、阳性预测值、阴性预测值及诊断准确度分别为27.42% (17/62) 、95.45% (42/44) 、89.47% (17/19) 、48.28% (42/87) 、55.66% (59/106), 而PPD试验的诊断结果依次为56.45% (35/62) 、84.09% (37/44) 、83.33% (35/42) 、57.81% (37/64) 、67.92% (72/106), T-SPOT.TB诊断结果则分别为95.16% (59/62) 、93.18% (41/44) 、 95.16% (59/62) 、93.18% (41/44) 、94.34% (100/106) 。其中T-SPOT.TB诊断的灵敏度、阴性预测值及准确度均显著高于 痰涂片AFB和PPD试验 ( P<0.05) 。血糖控制良好与控制不良者T-SPOT.TB检测诊断的灵敏度、特异度、阳性预测值、 阴性预测值和准确度相比差异均无统计学意义 ( P>0.05) 。 结论T-SPOT.TB检测在PTB合并DM的临床诊断上具有 更高的灵敏度和临床应用价值。