Pulmonary Alveolar Microlithiasis: Radiologic Findings of Eight Cases in Turkey

Objective: Pulmonary alveolar microlithiasis (PAM) is a rare idiopathic disease characterized by presence of diffuse innumerable minute calculi called microliths The aim of this report was to describe the radiographic findings of PAM with particular attention to features provided by chest X-ray and high resolution computerized tomography (HRCT). Material and Methods: We diagnosed three index cases of PAM who came from the same village in 1996. In 2005 we performed a study including 279 residents of that village by using microfilm screening to determine undiagnosed cases. Five additional cases of PAM were detected and underwent HRCT. HRCT and chest X-ray images of eight cases were assessed specifically for patterns, distribution, and profusion of pulmonary abnormalities. Results: Of eight cases, four were adults and four were children. Diffuse typical microcalcifications were detected in chest X-ray in three cases while reticulonodular pattern was seen in three cases and reticular pattern in two cases. Fine microcalcification, parenchymal band and fisssural prominence were the most common findings on HRCT. Small subpleural cysts were detected in five cases but only case 1 showed black pleural line in chest X-ray. One case had small subpleural bullae and bronchiectatic changes in both lower lobes predominantly in the left lung in HRCT. Conclusion: Relatives of a patient with PAM having reticular or reticulonodular pattern in chest X-ray must be investigated in detail for PAM because it can be the early stage of the disease. HRCT has a major importance for the detection of the rapid progression.