Background
Before thoracoscopic surgery, diagnosing tuberculous (TB) pleurisy was a
medical challenge. Thoracoscopy is the most accurate but expensive method for
TB pleurisy diagnosis. TB is common in low-income countries, where financial
limitations prevent the use of thoracoscopy, motivating the search for a cheaper
alternative.
Patients and methods
A prospective study was done from January 2019 to January 2023 to evaluate
diagnostic methods for patients with exudative pleural effusions (PE) of unknown
etiologies. The demographic, radiological, procedural, and histological data of
exudative PE patients were analyzed. All patients were examined for adenosine
deaminase (ADA) and lymphocyte/neutrophil ratio in pleural fluid. Ultrasoundguided
Abrams needle biopsy and video-assisted thoracoscopic surgery pleural
biopsies were obtained, and histopathological results were assessed.
Results
Of 250 patients with PE, 161 (64%) had TB PE, 72 (28.8%) had malignant
PE, and 17 (6.8%) had idiopathic PE. Sensitivity of ADA (≥40 U/l) was 88%,
lymphocyte/neutrophil ratio (≥0.75) was 86.1%, and their overall sensitivity was
91%. They had 93.2, 86.3, and 100% specificity, respectively. For ultrasoundguided
Abrams needle biopsy, the sensitivity of histopathology, culture, and
combined histopathology/culture was 66, 46.5, and 78.4%, respectively. All
were 100% specific. For thoracoscopic biopsy, the sensitivity of histopathology,
culture, and combined histopathology/culture was 100, 86.6, and 100%,
respectively. All were 100% specific. The assay sensitivity of pleural fluid and
tissue Xpert Mycobacterium tuberculosis/rifampin resistance was 12.5 and
49.7%, respectively. Both were 100% specific. Combining ADA more than or
equal to 40 U/l, lymphocyte/neutrophil ratio more than or equal to 0.75, and an
ultrasound-guided Abrams needle biopsy yielded 92.4% sensitivity and 100%
specificity.