Secondary Pulmonary Alveolar Proteinosis Following Treatment with Azacitidine for Myelodysplastic Syndrome.

Secondary pulmonary alveolar proteinosis (sPAP) is a complication of myelodysplastic syndrome (MDS). A 60-year-old woman was diagnosed with MDS with excess blasts-1. Fifty-four months after the initial diagnosis, treatment with azacitidine was initiated. Seventy-three months after the diagnosis, a bone marrow examination revealed increased myeloblasts, at which time computed tomography showed diffuse ground-glass opacities and interlobular septal thickening in the bilateral lower lung fields. A lung biopsy revealed the presence of PAP; therefore, the clinical diagnosis of MDS/sPAP was confirmed. Careful attention should be paid to the development of sPAP in MDS patients with pulmonary lesions during azacitidine treatment.