Diffuse alveolar hemorrhage in pediatrics: Etiologies and outcomes

Background: Many conditions, including autoimmune disease and idiopathic pulmonary hemosiderosis (IPH), can cause diffuse alveolar hemorrhage (DAH). Little is known about the epidemiology and outcomes in children. Objectives: This retrospective cohort study sought to describe the etiologies and outcomes of DAH in pediatric patients at a tertiary care center. Methods: This study involved review of patient records with diagnostic codes or bronchoscopy reports suggestive of pulmonary hemorrhage at a large children's hospital over 11 years (2010-2020). Patients were included if they met criteria for DAH, defined as bilateral pulmonary infiltrates and at least one of the following: (1) hemoptysis, (2) blood visible on bronchoscopic exam without apparent airway source, or (3) DAH noted on biopsy or autopsy. Infants less than 10 days corrected gestational age were excluded. Results: Seventy-one children with DAH were included in the analysis. Cardiovascular disease was the most common etiology. Bleeding diathesis was common, but all patients had other causes of DAH. Patients with IPH were younger than those with autoimmune disease (p < .001). Most (77%) patients required mechanical ventilation, though this was less common among patients with autoimmune disease. Overall mortality was high (37%) but varied based on underlying etiology; mortality was higher in patients with cardiovascular disease (65%) while no deaths were seen in patients with autoimmune disease or IPH (p = .002). Survivors of DAH who performed pulmonary function tests had normal lung function. Conclusions: DAH frequently causes respiratory failure in children. In our cohort, mortality was highest in patients with cardiovascular disease.