Background: Familial alveolar microlithiasis is a rare lung disease. In this study we describe the cytologic features of this disease in bronchoalveolar lavage.
Case: A 10-year-old girl and her uncle, a 50-year-old man, had dyspnea and diffuse interstitial pattern on chest radiograph with no defined cause at a period of 10 years apart. Open lung biopsy in the girl and transbronchial lung biopsy plus bronchoalveolar lavage (BAL) in the man were per-formed to determine the diagnosis. In cyopen lung biopsy the diagnosis was alveolar microlithiasis. BAL revealed rehtypical microliths (calcospherites), and th transbronchial lung biopsy performed in the same patient failed to disclose superficially reset any significant pathology. In cytologic a smears, extracellular and intracellular concentrically layered purple-brown, round-to-oval microliths were clearly seen. Cyanophilic periodic acid-Schiff positive intracytoplasmic amorphous material was also frequently seen in alveolar macrophages.
Conclusion: Familial alveolar microlithiasis is a rare interstitial lung disease that can be easily diagnosed by BAL. This procedure is a very useful tool in diagnosing and classifying some interstitial lung diseases.