Clinical features of secondary pulmonary alveolar proteinosis associated with myelodysplastic syndrome

Abstract

Rationale:Pulmonary alveolar proteinosis (PAP) is a rare lung disorder characterized by the abnormal accumulation of alveolar surfactant protein in alveolar spaces. Secondary PAP can result from myelodysplastic syndrome (MDS).Patient concerns:But most reports described a single case; here we reported 2 cases of PAP secondary to MDS. One case developed secondary PAP at the same time as MDS, and the other developed during the course of MDS.Diagnoses:The diagnosis of PAP was made by bronchoalveolar lavage and based on the identification of periodic acid-Schiff-positive proteinaceous material. Chest high resolution CT (HRCT) scans showed variable distribution of ground glass opacities, but crazy-paving appearance was not seen in our 2 cases.Interventions:Because the patients’ general conditions were poor, whole lung lavage was not used in the 2 cases.Outcomes:And the 2 cases’ prognoses were poor.Lessons:In conclusion, pulmonary physicians should suspect the possibility of secondary PAP when they encounter unexplained pulmonary infiltrates with some hematologic or infectious disease that shows diffuse bilateral GGO on an HRCT scan.

Secondary Pulmonary Alveolar Proteinosis Following Treatment with Azacitidine for Myelodysplastic Syndrome

“…The emergence of sPAP is observed not only at the diagnosis of MDS but also under various clinical conditions (8)(9)(10)(11)(12). A previous study showed the development of sPAP at the time of disease progression after treatment with cytotoxic agents (10); however, limited information is currently available on the emergence of sPAP in MDS patients treated Intern Med 59: 1081-1086, 2020 DOI: 10.2169/internalmedicine.3770-19 We herein report a case of MDS/sPAP that was diagnosed during treatment with azacitidine for high-risk MDS.…”

Subcutaneous Sweet syndrome mimicking cellulitis in a patient with myelodysplastic syndrome and subsequent secondary pulmonary alveolar proteinosis

“…Idiopathic PAP occurs as a result of autoantibodies against GM-CSF, whereas secondary PAP may result from functional impairment of the GM-CSF receptor on alveolar macrophages and/or an abnormal signal transduction pathway after interaction of GM-CSF and its receptor in association with haematological disorders, immunosuppressive drugs, dust inhalation, acute silicosis or certain chronic infections. 4,5 Although the exact pathogenesis of secondary PAP associated with haematological malignancy remains unknown, alveolar macrophages derived from malignant clones may be defective or have an abnormal GM-CSF transduction pathway. Therapy for secondary PAP mainly depends on the treatment used for the underlying disease.…”