Department of Pulmonary Medicine, Rajagiri Hospital, Kochi, Kerala, India.
Department of Clinical Epidemiologist, Rajagiri Hospital, Kochi, Kerala, India.
Int J Mycobacteriol. 2021 Oct-Dec;10(4):405-410. doi: 10.4103/ijmy.ijmy_214_21.
Establishing the etiology of exudative pleural effusions in the setting of an unrewarding pleural fluid analysis often requires biopsies from the parietal pleura. However, it may be noted that diagnosis such as pulmonary embolism and connective tissue diseases can result in an exudative pleural effusion where a pleural biopsy can yield nonspecific results. Medical thoracoscopy (MT) is a minimally invasive procedure performed under local anesthesia or moderate sedation with excellent yield and favorable safety profile. We analyzed the diagnostic yield of MT for exudative pleural effusions after employing a rigid diagnostic algorithm. The study was undertaken to ascertain the yield of MT in establishing the diagnosis in diagnosis of exudative pleural effusions, to find out the relative contribution of pleural tuberculosis (TB) as a cause of undiagnosed exudative pleural effusion, to describe the etiology of undiagnosed exudative pleural effusion in patients undergoing MT and to determine the correlation between pleural fluid adenosine deaminase (ADA) levels and TB pleuritis in patients undergoing MT.
This was a retrospective study. Patients with undiagnosed exudative pleural effusion were included in the study. MT was performed with semirigid thoracoscope (Olympus LTF 160) under local anesthesia and conscious sedation. Gross appearance and ADA level of pleural fluid were noted. Pleural biopsy material was subjected to histopathology examination and culture for mycobacteria along with cartridge-based nucleic acid amplification test for TB. The yield of MT for establishing the etiology of pleural effusion and the relative contribution of tuberculous pleuritis as a cause of undiagnosed pleural effusion was ascertained. Correlation of pleural fluid ADA levels was done with a final diagnosis of TB pleuritis in patients undergoing MT.
Twenty-five patients with undiagnosed exudative pleural effusion underwent thoracoscopy of which 16 were male and 9 were female. MT was able to establish the diagnosis in all cases, providing a diagnostic yield of 100%. Histopathological examination of biopsy specimens yielded a diagnosis of malignant involvement of pleura in 10 patients and granulomatous pleuritis consistent with TB in 14 patients. Pleural TB contributed to 60% of undiagnosed pleural effusions in the present study. The mean ADA value among those who turned positive was 56.338 and 35.300 among those who turned negative using genexpert, which was found to be statistically significant. A value of 31 IU/L showed a sensitivity of 93.3% and specificity of 99.8% and hence can be taken as a cut off value for the diagnosis of pleural TB based on receiver-operating characteristic analysis.
TB contributed to 60% of undiagnosed exudative pleural effusions in the present study. MT had 100% yield in the diagnosis of undiagnosed exudative effusions. Pleural fluid ADA levels may help in differentiating TB versus malignant effusion.
在胸膜液分析结果不明确的情况下，要明确渗出性胸腔积液的病因，通常需要对壁层胸膜进行活检。然而，需要注意的是，肺栓塞和结缔组织疾病等诊断结果也可能导致渗出性胸腔积液，此时胸膜活检的结果可能并不具有特异性。内科胸腔镜检查（MT）是一种微创程序，在局部麻醉或中度镇静下进行，具有极好的收益和良好的安全性。我们分析了在采用严格的诊断算法后，MT 对渗出性胸腔积液的诊断效果。该研究旨在确定 MT 在确定渗出性胸腔积液诊断中的效果，明确结核性胸膜炎（TB）在未明确病因的渗出性胸腔积液中的相对占比，描述接受 MT 治疗的患者中未明确病因的渗出性胸腔积液的病因，并确定 MT 患者胸腔液腺苷脱氨酶（ADA）水平与 TB 胸膜炎之间的相关性。
这是一项回顾性研究。本研究纳入了未明确病因的渗出性胸腔积液患者。在局部麻醉和清醒镇静下，使用半刚性胸腔镜（Olympus LTF 160）进行 MT。记录胸腔液的大体外观和 ADA 水平。对胸膜活检标本进行组织病理学检查和分枝杆菌培养，以及基于试剂盒的结核分枝杆菌核酸扩增检测。确定 MT 对胸腔积液病因的诊断效果，并确定结核性胸膜炎作为未明确病因的胸腔积液的病因的相对占比。对 MT 患者胸腔液 ADA 水平与 TB 胸膜炎的最终诊断进行相关性分析。
25 例未明确病因的渗出性胸腔积液患者接受了胸腔镜检查，其中 16 例为男性，9 例为女性。MT 能够在所有病例中确定诊断，诊断效果达到 100%。活检标本的组织病理学检查结果显示，10 例患者为胸膜恶性受累，14 例患者为符合结核的肉芽肿性胸膜炎。在本研究中，TB 导致 60%的未明确病因的胸腔积液。使用 genexpert 检测结果为阳性的患者平均 ADA 值为 56.338，结果为阴性的患者平均 ADA 值为 35.300，差异具有统计学意义。31 IU/L 的 ADA 值具有 93.3%的敏感性和 99.8%的特异性，因此可作为基于受试者工作特征分析的胸腔 TB 诊断的截断值。
在本研究中，TB 导致 60%的未明确病因的渗出性胸腔积液。MT 在诊断未明确渗出性胸腔积液方面的效果达到 100%。胸腔液 ADA 水平有助于鉴别 TB 与恶性胸腔积液。
