Paraffin-embedded Sample Test Promotes the Diagnosis of Tuberculous Pleurisy.

Context: Tuberculous pleurisy (TP) is the most common manifestation of extrapulmonary tuberculosis and the most frequent cause of pleural effusion (PE). Clinicians make a definitive diagnosis of TP based on the isolation of the mycobacterium tuberculosis (MTB) from PE or a pleural biopsy. Since the currently available tests for TP all have limitations in making a definitive diagnosis, clinicians urgently need new diagnostic tests.
Objective: The study intended to compare the value in clinically diagnosing TP of the paraffin-embedded sample test (PEST), using pleural-effusion samples; an adenosine deaminase assay (ADA) using pleural fluid; and the T cell enzyme-linked immunospot test (T-SPOT), using peripheral-blood.
Design: The research team performed a retrospective observational study.
Setting: The study took place at the Sir Run Run Hospital, Nanjing Medical University in Nanjing, Jiangsu, China.
Participants: Participants were 37 patients with suspected TP who had been admitted to the hospital between September 2018 and December 2022.
Outcome Measures: The research team assessed the diagnostic performance of PEST, ADA, and T-SPOT in the TP group, calculating the positive rate, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of the tests.
Results: Among the 37 participants, the testing confirmed that 24 had TP (64.86%), with 13 not having TP (35.14%). The PEST test produced a sensitivity of 83.3% for TP, with 20 out of 24 participants in the TP group testing positive (95% CI: 61.8 to 94.5), which was superior to the ADA, with only 9 out of the 24 participants (37.5%) in the TP group testing positive (95% CI: 19.6 to 59.2), with P < .001.
Conclusions: The PEST test possesses a high diagnostic value, and clinicians can use it as a time-saving, noninvasive, and highly sensitive method for TP diagnosis. It can be adjunct method to the currently used tests for diagnosing TP. A combination of several detection methods could promote effective treatment.