Successful Inhaled Sargramostim Therapy for Autoimmune Pulmonary Alveolar Proteinosis in a Patient with an Intellectual Disability: A Caregiver-Assisted Approach.

Autoimmune pulmonary alveolar proteinosis (aPAP) can be difficult to diagnose in the absence of typical imaging findings and when bronchoscopy is impractical. A 40-year-old man with an intellectual disability was initially suspected to have bird-related hypersensitivity pneumonitis based on feather duvet exposure, positive bird antigen-specific IgG, and diffuse ground-glass opacities. Progression despite corticosteroid treatment and markedly elevated anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies and KL-6 suggested aPAP. Inhaled sargramostim was administered using a pediatric soft mask with caregiver assistance because inspiratory synchronization was challenging. Oxygenation, A-aDO2, biomarkers, and imaging improved, and the patient remained stable for more than 12 months after treatment discontinuation.