Introduction: Cryptogenic organising pneumonia is a particular form of inflammatory and fibroproliferative lung disease. The disease onset is subacute with cough, dyspnoea, fever, weight loss, and elevation of biological inflammatory markers. Chest imaging usually shows multifocal alveolar opacities predominating in the subpleural regions. Lung biopsy reveals budding connective tissue filling the distal airspaces.
Case outline: A 57-year-old electrician complaining of cough, dyspnoea, and fatigue was diagnosed with pneumonia and treated with antibiotics and antihistaminics. After clinical and radiographic progression of the disease, open lung biopsy was performed, some 15 months after the disease onset. The diagnosis of cryptogenic organising pneumonia was made. The patient was treated with oral and inhalatory corticosteroids and finally with cytostatics, which led to a partial improvement of his condition. However, work capacity was lost and the quality of life seriously deteriorated.
Conclusion: The diagnosis is established by combining clinical, radiological and histological criteria. Similarities with other disease processes can lead to a delayed or erroneous diagnosis. Most patients respond well to corticosteroid therapy (prednisone or methyl-prednisolone). Relapses are frequent but can generally be controlled.