Tuberculous Pleural Effusion
A 34-year-old man whose father was treated for pulmonary tuberculosis last year has 6 weeks of fever, night sweats, 7 kg weight loss, and blood-streaked sputum. He has never smoked. There is stony dullness and absent breath sounds over the right lower chest, with a central trachea. Pleural aspirate is straw coloured and lymphocyte predominant, with protein 52 g/L and adenosine deaminase 78 U/L. What is the most likely diagnosis?
- A.Effusion secondary to congestive heart failure
- B.Bronchogenic carcinoma obstructing the right main bronchus
- C.Tuberculous pleuritisCorrect
- D.Esophageal rupture with pleural contamination
Explanation
A lymphocyte-predominant exudate with a high adenosine deaminase level in a young non-smoker with weeks of fever, night sweats, weight loss and a household tuberculosis contact is characteristic of tuberculous pleuritis, which results from a delayed hypersensitivity reaction to mycobacterial antigens reaching the pleural space. Adenosine deaminase above roughly 40 U/L in a lymphocytic exudate has high sensitivity and specificity for tuberculosis in endemic settings, and pleural biopsy with granulomas or culture is confirmatory when needed since fluid smear and culture yield is low. The absence of tracheal and apical shift is an important clue: a moderate effusion alone would push the mediastinum away, so a midline mediastinum implies a balancing volume-losing process or simply a modest effusion, but it argues strongly against a large tension-type collection. A bronchogenic carcinoma obstructing the ipsilateral bronchus would cause collapse and pull the trachea toward the lesion, and would be unusual in a 34-year-old who has never smoked, although hemoptysis and constitutional symptoms overlap. Heart failure produces bilateral transudative effusions with raised jugular venous pressure, orthopnea and a third heart sound, not a unilateral lymphocytic exudate with weight loss. Esophageal rupture presents acutely with severe chest pain, subcutaneous emphysema and an effusion with very low pH and high amylase after vomiting or instrumentation. Treatment is standard antituberculous chemotherapy, and most effusions resorb without drainage unless the patient is symptomatic or the fluid is loculated.
Why each option
- A.
- Heart failure effusions are usually bilateral transudates with raised jugular venous pressure and no weight loss or night sweats.
- B.
- Bronchial obstruction by tumour causes collapse with tracheal shift toward the lesion and is unlikely at 34 years in a never-smoker.
- C.
- Correct. Lymphocytic exudate with adenosine deaminase 78 U/L plus constitutional symptoms and a household contact indicates tuberculous pleuritis.
- D.
- Esophageal rupture is an acute event with severe pain, surgical emphysema and pleural fluid of low pH and high amylase.
Reference: UpToDate 2025, Tuberculous pleural effusion
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