Pulmonary alveolar microlithiasis is a rare disease, characterized by extensive phosphocalcic concretions within the alveolar spaces. Pulmonary alveolar microlithiasis is usually asymptomatic and is incidentally found because radiologic findings are characteristic. In about half of the cases, it is an autosomal recessive disorder due to mutations in the SLC34A2 gene. Pulmonary alveolar microlithiasis can easily be diagnosed by bronchioloalveolar lavage or transbronchial biopsy. The clinical course is usually stable during several years and lung transplantation is the only effective treatment when a respiratory failure occurs. A 49-year-old woman was referred with a restrictive respiratory failure due to a pulmonary alveolar microlithiasis incidentally discovered on a chest radiography when she was 11 and was confirmed by surgical lung biopsy. She was asymptomatic until she was 43 when she presented a progressive dyspnea leading to continuous oxygen administration 4 years later. Laboratory findings only showed a polyglobulia related to hypoxemia. Chest radiography and computed tomography chest scan revealed a bilateral symmetric micronodular pattern. She underwent a lung transplantation when she was 49. Pathological examination confirmed the diagnosis of diffuse pulmonary alveolar microlithiasis with interstitial fibrosis. The patient died 3 months after surgery in an infectious context.