Pulmonary alveolar microlithiasis: a rare familial inheritance with report of six cases in a family. Contribution of six new cases to the number of case reports in Turkey.
Pulmonary alveolar microlithiasis (PAM) is a lung disease characterized by deposits of calcium within the alveoli. Our aim was to emphasize the familial character and the clinical features of the disease, and to draw attention to the increasing number of Turkish patients reported in the world. We detected 6 cases of PAM. Three cases had been diagnosed 4 years earlier, and 3 new cases were detected during the screening of the family members. All patients were male and the mean age was 11.5 ranging between 5 and 29 years. Five of the patients were cousins and the other one was their uncle. Radiographic studies showed a sand-like appearance in all patients. One case showed small subpleural bullae and bronchiectatic changes in both lower lobes in recent high-resolution CT scans, while his CT performed 4 years ago showed only sand-like appearance. The cases were diagnosed with the demonstration of microliths by bronchoalveolar lavage in 5 patients and transbronchial biopsy in 1. Recently reported cases from Turkey have constituted a considerable percentage among all cases in the world. In conclusion, (1) our patients constitute one of the largest series of cases reported in one family in the world. The disease seems to have familial and racial characteristics. The Turkish race has to be further investigated for genetic transmission. (2) Contrary to female predominance in previous reports, all 6 cases were male and 5 of them were below 12 years of age. (3) The disorder may show rapid progression in some cases probably due to the severity of the genetic disturbance.