A 24-year-old man presents with gradual right-sided chest discomfort and low-grade fever for 3 weeks. Chest X-ray shows a moderate right pleural effusion. Pleural fluid: straw coloured, protein 4.9 g/dL, LDH 420 IU/L, lymphocyte predominant, glucose 70 mg/dL, adenosine deaminase 58 IU/L. GeneXpert on fluid is negative. What is the most likely diagnosis?

• A Parapneumonic effusion
• B Tuberculous pleural effusion ✓
• C Rheumatoid pleuritis
• D Malignant pleural effusion

Explanation

Tuberculous pleurisy classically produces a lymphocytic exudate with high adenosine deaminase; a value above about 40 IU/L in a young patient in a TB-endemic country like India has high sensitivity and specificity, and a negative GeneXpert does not exclude it because bacillary load in the fluid is paucibacillary. Parapneumonic effusions are neutrophil predominant with low glucose and pH, rheumatoid effusions show very low glucose, and malignancy is unlikely at this age.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.