Abstract
Organising pneumonia (OP), a rare form of interstitial lung disease (ILD), is frequently misdiagnosed as community-acquired pneumonia, leading to delays in appropriate treatment. While the cryptogenic form (cryptogenic organising pneumonia [COP]) has no identifiable cause, secondary organising pneumonia (SOP) has been associated with infections, drug reactions, autoimmune diseases, radiation exposure and, increasingly, the use of monoclonal antibodies. Following a thorough literature review, we concluded that an accurate diagnosis is best achieved through a combination of clinical and biological data, computed tomography (CT) imaging and, when possible, histological analysis. Corticosteroids have shown high efficacy; however, the relapse rate remains significant, emphasising the need for close patient monitoring as a standard of care.