Adult Pulmonary Alveolar Proteinosis

Pulmonary alveolar proteinosis (PAP) is a rare lung disorder that results from accumulation of lipoproteinaceous material in the alveolar spaces, due to abnormal surfactant homeostasis. Patients with PAP may be asymptomatic, or present with varying degrees of dyspnea and in some cases, even respiratory failure. Antibodies to GM-CSF, a glycoprotein cytokine critical for lung immunity and alveolar macrophage maturation, is pathogenic for autoimmune PAP (>90% of cases). Bronchoscopy is critical for confirmation of diagnosis. Treatment for symptomatic PAP includes modalities such as whole lung lavage, supplementation of GM-CSF, and, rarely, lung transplantation.