Severe autoimmune diffuse alveolar hemorrhage in children; early diagnosis and initiation of therapeutic plasma exchange may improve clinical outcomes.

Introduction: Diffuse alveolar hemorrhage (DAH) is a rare but life-threatening pulmonary complication in children, presenting with hemoptysis, anemia, diffuse infiltrates, and respiratory failure. Autoimmune diseases such as systemic lupus erythematosus (SLE) and ANCA-associated vasculitis (AAV) account for 30%-40% of pediatric DAH cases. Pediatric evidence is limited to case reports and small series. We aimed to characterize the clinical course, management, and outcomes of pediatric patients with autoimmune DAH requiring intensive care. Methods: We conducted a retrospective cohort study at a single tertiary pediatric institution, identifying 6 patients admitted to the ICU from 2013 to 2024 with DAH secondary to SLE or AAV. Results: All six patients (5 females; age 14-17) were critically ill. Five required MV (median 18 days, IQR: 18-25), two required high-frequency oscillatory ventilation (HFOV) (6, 10 days), and three required VV-ECMO (8, 9, and 45 days). Four had new-onset autoimmune diagnoses on admission. All received high-dose corticosteroids and therapeutic plasma exchange (TPE) (mean 6.5 ± 2.6 sessions); adjunctive therapies included cyclophosphamide, rituximab, IVIG, mycophenolate mofetil, and hydroxychloroquine. TPE was initiated within 24 h of DAH diagnosis in most cases. Two patients with less severe presentations had delayed initiation, and one progressed to HFOV. All patients on ECMO were successfully decannulated; one died from Conclusion: Autoimmune DAH in pediatric patients carries high morbidity, often requiring advanced respiratory support and multimodal immunosuppression. Early diagnostics work up and initiation of TPE may improve outcomes. Further prospective pediatric study would be necessary to guide standardized treatment protocols.