Organizing Pneumonia As the Initial Manifestation of Systemic Lupus Erythematosus: Case Report and Literature Review.

Systemic lupus erythematosus (SLE) can affect multiple organs, including the lungs, with a reported frequency ranging from 20% to 90%. Organizing pneumonia (OP) is a rare and uncommon presentation that may be life-threatening. A 42-year-old male presented with respiratory symptoms, fever, a history of recurrent pneumonia, and the development of oral ulcers. Antinuclear antibodies were positive with an AC-01 pattern, and he scored 10 points according to the 2022 European Alliance of Associations for Rheumatology (EULAR) classification criteria, establishing the diagnosis of SLE. Corticosteroid therapy was initiated with clinical resolution. We conducted a search in the PubMed database for cases of systemic lupus erythematosus that initially presented with organizing pneumonia. The search terms used were "organization" or "organized", or "organizing", and "pneumonia" and "lupus" or "systemic lupus erythematosus". It should be noted that no time filter was applied, and reports of cases of individuals under 18 years of age were excluded. OP was diagnosed as the initial manifestation of SLE, representing a diagnostic challenge in the absence of other guiding symptoms. We identified 19 case reports describing OP as the initial presentation of SLE. This case illustrates the diagnostic complexity and variability of SLE, and how OP, in the appropriate clinical context, should raise suspicion of SLE onset.