Case series of Pulmonary Alveolar Microlithiasis from India

Pulmonary alveolar microlithiasis (PAM) is a rare disease characterised by calcific deposits in lung parenchyma. PAM being a progressive disease with dissociation between severity of clinical symptoms and radiological picture, it is often detected incidentally. Mutations in the SLC34A2 gene encoding the type IIb sodium phosphate cotransporter in alveolar type II cells are considered to be involved in the pathogenesis of PAM. The majority of the patients are diagnosed usually between the ages of 20 and 40 years, although paediatric PAM has also been reported. Diagnosis is confirmed by combination of radiological features, bronchial lavage and histopathological testing. At present, lung transplant is the only definitive treatment available. Though rare, the prevalence of PAM is worldwide. Till June 2018, 86 cases have been reported from India and 1042 cases have been reported worldwide. We report three cases from India, including a student, cement factory worker and a tailor, which will highlight the varied clinical and radiological presentations of this rare disease along with the response to treatment.