Crohn's disease presenting with pleural effusion: a case report.

Crohn's disease (CD) is a granulomatous inflammatory bowel disease. Around 25% of CD patients exhibit extraintestinal manifestations, though pulmonary involvement is rare. This study presents a case of CD causing pleural effusion. A 43-year-old man visited the pulmonology clinic with a dry cough for one-month, right-side pleuritic chest pain, and exertional dyspnea. He was treated with antihistamines and antitussive syrup, with incomplete relief. A chest CT scan showed bilateral mild pleural effusion. Given his occasional black stools and high serum calprotectin, a colonoscopy confirmed CD. Pulmonary manifestations may involve airway, parenchymal, and interstitial pathologies, but no distinctive pathological findings differentiate CD's pulmonary manifestations from other causes. In conclusion, isolated bilateral pleural effusion and the underlying pleuritis as a pulmonary manifestation of CD-characterized by dry cough and pleuritic chest pain, particularly preceding the diagnosis of CD-is extremely rare but possible.