Validity of pleural fluid protein in differentiating tuberculous from malignant pleural effusion

Background: Pleural tuberculosis is one of the commonest causes of pleural effusion in regions endemic for tuberculosis including Pakistan. Objective: To study the types of clinico-radiological presentations of pleural tuberculosis and analyze misuse of antibiotics prior to its diagnosis. Methodology: Prospective analysis of clinico-radiological features and misuse of antibiotics among 58 patients with pleural tuberculosis, over 24 months (May 2015 to May 2017), presenting at the department of pulmonology, Shaikh Zayed Hospital, FPGMI Lahore, Pakistan. Results: The study included 58 patients including 37 males (64%) and 21 females (36%), having ages in the range of 14 to 72 years. Thirty three (56.9%) were indoor and 25 (43.1%) were OPD patients; 38 (48.3%) had left sided pleural effusion, 38 (48.3%) with right pleurisy & 2 (3.4%) had bilateral pleural effusions. Small sized pleural effusions on chest radiographs were seen in 6 (10.34%), moderate effusions in 22 (37.93%), larger effusions in 25 (43.10%) and massive effusions in 5 (8.62%) patients with 50% having septations on ultrasound chest examination. Diagnosis of pleural TB was made on the basis of either positive pleural biopsy (caseating granulomatous inflammation) with lymphocytic (51.72%) or neutrophilic (5.17%) exudative effusions or exudative lymphocytic effusion alone (43.10%). Duration of illness prior to hospital visit was ≤ 2 weeks in 24 (41.4%), 2-3 weeks in 14 (24.1%) and ≥ 4 weeks in 20 (34.5%) patients. Majority (63.2%) of the patients had intermediate to high grade continuous or intermittent pyrexia while 24 (41.4%) had low grade continuous fever with 24 (41.4%) subjects experiencing night sweats. Forty (69%) patients had cough and 13 (22.4%) had mild sputum production. Forty three (74.1%) patients also had dyspnea. Chest pain was present in 32 (55%) and 25 (43.1%) had pain of pleuritic nature. Wheeze and hemoptysis were the least frequent symptoms in 9 (15.5%) and 2 (3.4%) individuals respectively. Forty nine (84.5%) patients had visited physicians prior to presenting to the hospital and misuse of antibiotics was reported by 42 (72.4%) patients. Association of age with duration of illness prior to hospital visit showed statistical significance as majority (56.2%) of patients having ≤ 30 years of age had ≤ 2 weeks duration of illness compared to only 3 patients in 31-50 years of age group and 3 subjects having ages > 50 years (p-value = 0.048). Association of young age ≤ 30 years with other parameters including fever grade (p-value = 0.004), wheeze (p-value=0.050), physicians' visits (p-value = 0.075) and antibiotics misuse (p-value = 0.026) also revealed significant associations. Conclusion: Tuberculous pleural effusions appear moderate to large on chest radiographs, and presents in an acute manner, and should be investigated earlier to avoid diagnostic delay and prevent misuse of antibiotics.