Hematopoietic stem cell transplantation for pulmonary alveolar proteinosis associated with primary immunodeficiency disease

Pulmonary alveolar proteinosis (PAP) is a rare disorder that is characterized by the excessive accumulation of surfactant-like materials in the alveoli, leading to hypoxemic respiratory failure. We describe two Japanese infants with PAP associated with hypogammaglobulinemia and monocytopenia. These patients may have underlying primary immunodeficiency (PID) and were successfully treated with allogeneic hematopoietic stem cell transplantation (HSCT). This report indicates that allogeneic HSCT may provide a curative treatment for PAP associated with PID.