Pulmonary alveolar proteinosis: Experience from a tertiary care center and systematic review of Indian literature

Background: Pulmonary alveolar proteinosis (PAP) is a rare disorder characterized by deposition of lipoproteinaceous material within alveoli, with a variable clinical course. Here, we report an experience of management of PAP at our center. A systematic review of previously reported cases from India is also included in the article. Materials and Methods: This study included patients with primary PAP managed at our center from 2009 to 2015. Diagnosis of primary PAP was based on histopathologic diagnosis on bronchoalveolar lavage or transbronchial lung biopsy and absence of causes of secondary PAP. For systematic review of Indian publications, the literature search was performed using PubMed and EMBASE databases using the terms "pulmonary alveolar proteinosis'" or "alveolar proteinosis" and "India" or "Indian." Results: During the above-specified period, five patients with diagnosis of PAP were admitted at our center. Median age of patients was 32 years (interquartile range [IQR] 30.5-59); 80% were female. Mean duration (+/- standard deviation) of symptoms was 6.2 (+/- 1.79) months. Anti-granulocyte-macrophage colony stimulating factor (GM-CSF) antibodies were elevated in 4 out of 5 patients (80%). For management, whole lung lavage (WLL) was done for four patients with median volume of 32.5 (IQR 18-74) L per patient. All the patients showed significant symptomatic as well as improvement in physiological parameters. Subcutaneous GM-CSF and ambroxol were given to 3 patients and 1 patient, respectively. The median follow-up of all patients was 18 (IQR 5-44) months. A systematic review of all Indian studies of PAP revealed thirty publications. Conclusions: WLL is the most common, effective, and safe therapy in patients with PAP. GM-CSF administration is an efficacious treatment for patients with incomplete response after WLL.