Untangling the Web – An approach to Cryptogenic Organizing Pneumonia

Cryptogenic organizing pneumonia (COP) is an idiopathic interstitial lung disease characterized by the formation of fibro-inflammatory buds, known as Masson bodies, within the alveolar airspaces. Unlike idiopathic pulmonary fibrosis, COP typically preserves the underlying lung architecture, offering a higher potential for recovery. Patients usually present in their 50s or 60s with subacute symptoms like nonproductive cough, exertional dyspnea, and constitutional signs such as fever, often failing to respond to standard antibiotics. Diagnosis relies on high-resolution CT imaging showing peripheral patchy consolidations—sometimes manifesting as the "reverse batwing" or "reversed halo" signs—and the exclusion of secondary causes like connective tissue diseases or drug toxicities. While mild cases may resolve spontaneously, the standard treatment involves a prolonged corticosteroid taper, which frequently yields dramatic clinical improvement within days. Despite a favorable prognosis, clinicians must monitor for common relapses during dosage reduction and consider alternative immunosuppressants for steroid-resistant cases.