A 41-year-old man with no toxic habits and a history of lactose intolerance, diagnosed in 2003 with Crohn's disease with an inflammatory pattern and ileal involvement, which had started two years earlier with an episode of uveitis. He is currently in clinical remission without any maintenance treatment.
For the last two months he has had an upper respiratory tract cold, accompanied in the last few days by cough, whitish expectoration and fever of 38ºC. Initially diagnosed with right basal pneumonia, he was treated with antibiotics and mucolytics with little improvement. He subsequently presented with dyspnoea, purulent expectoration, asthenia and loss of 8-10 kg. After failing to improve, he was referred to hospital and admitted to the pneumology department.
Physical examination revealed pale skin, temperature: 37.2 ºC and pulmonary auscultation with crackles in the right base.
-Complementary examinations:
- Systematic: ESR: 66 mm 1 hour, leukocytes: 6,900/ul with normal formula, red blood cells: 4,570,000/ul; Hb: 11.9 g/dl; Ht: 35.6%; platelets: 366,000/ul. Biochemistry: no significant findings. Coagulation: normal. O2 sat: 95%.
- Blood cultures negative for anaerobes and aerobes. HIV serology: negative. Sputum bacteriology negative. Urine bacterial Ag: negative for pneumococcus and legionella.
- Chest X-ray on admission: alveolar infiltrates in the right base and minimal infiltrates in the left base, which in subsequent radiological controls became migratory to segment 6, also affecting the right middle lobe. Days later, condensation was observed in the right upper lobe, reducing the basal infiltrates.
- Spirometry: FVC: 2.52 l (56%); FEV1: 2.23 l (60%); FEV1/VC: 78%; MMEF25-75: 1.96 l (46%): non-obstructive ventilatory failure.
- Thoracic CT: extensive parenchymal consolidation in the right upper lobe; resolution consolidation and volume loss in the right middle lobe; partial resolution consolidation in the right lower lobe with image of alveolar infiltrate and partial resolution image in the posterior segment of the left upper lobe.

- Following the results, fibrobronchoscopy was performed with bronchoalveolar lavage (BAL) and transbronchial biopsy (BTB): no endoluminal lesions or mucosal alteration were observed. BAL microbiology: normal upper airway flora with negative culture of Legionella, Gram, BAAR and fungi. BAL: 80 cells/mm3, 65% macrophages, 25% lymphocytes (increased), 5% eosinophils and 5% PMN. Lymphocyte populations: CD4/CD8 ratio: 0.87. Transbronchial biopsy: widened interalveolar septa due to chronic inflammation and fibrosis. Alveolar cell hyperplasia with pneumocyte desquamation at the lumen and PAS-negative granular exudate. Myxoid granulation tissue emerging from terminal bronchi into the lumen. No granulomatous lesions or hyaline membranes. All of the above is compatible with organised pneumonia with bronchiolitis obliterans.
Treatment with prednisone at a dose of 1 mg/kg/day was started, and the fever subsided and the rest of the symptoms improved. At one month and three months the patient was asymptomatic and radiological controls were normal.

