Raised ADA in exudative pleural fluid with positive exposure is not tubercular

Abstract

Parapneumonic effusions are more familiar with bacterial pneumonia than viral pneumonia. In a tuberculosis-endemic country like India, viral parapneumonic effusions can be misdiagnosed as tubercular effusions and unnecessarily treated with antitubercular therapy. Here, we present an observational single case study of a middle-aged female who presented with shortness of breath a few days following an episode of atypical pneumonia. On examination, she was in acute respiratory distress with reduced air entry on the right side of her chest. Chest radiograph showed right-sided pleural effusion, which was exudative with lymphocytic predominance on diagnostic thoracocentesis with raised ADA level. Workup on pleural fluid was negative for bacteria as well as tuberculosis. Therapeutic thoracocentesis was done to relieve dyspnea, and she was managed conservatively without any antimicrobial therapy. It was thus a case of simple parapneumonic effusion, which, if misdiagnosed as tuberculous effusion considering its endemicity, would have resulted in unwanted exposure of the patient to antitubercular drugs and the associated drug side effects. This case study proves that contact exposure and exudative pleural effusion are not pathognomonic of tuberculosis.