Microlithiase alvéolaire pulmonaire : à propos de deux cas familiaux au Maroc

Abstract

Pulmonary alveolar microlithiasis (PAM) is a rare autosomal recessive disease. The majority of patients are asymptomatic. The disease is often diagnosed on routine radiological examination. We report two familial cases of PAM. A 17-year-old girl with a chest X-ray showing an alveolar syndrome, especially on the right side, a bronchointerstitial syndrome, and diffuse calcifications. The thoracic CT scan showed calcified micro- and macronodules with pleural and pericardial calcifications. Respiratory function tests showed restrictive syndrome and normal blood gas values suggestive if PAM, which was confirmed by the presence of microliths in bronchoalveolar lavage (BAL). Family investigation led to chest radiograph of a 14-year-old sister who was asymptomatic but presented with an aspect of "sandstorm" calcifications. PAM is known to be radio-clinically dissociative. In typical cases, radiology can suggest the diagnosis, which is often confirmed by SLC34A2 mutation or microliths in BAL or sputum. The prognosis is compromised in the long-term. The only effective treatment nowadays is lung transplantation.