PULMONARY ALVEOLAR MICROLITHIASIS IN CHILDREN

Two asymptomatic Turkish sibs are presented, a 4-year-old boy and his 7-year-old sister, with pulmonary alveolar microlithiasis (PAM) confir med by transbronchial lung biopsy and bronchoalveolar lavage. Chest ra diographs and high resolution CT demonstrated widespread intra-alveola r calcifications in both lungs. The lesions were sharply defined and l ess than 1 mm in diameter. CT documented a high concentration of micro liths along the bronchovascular bundles, the intralobular fissure and the (sub)pleural lung parenchyma. The combination of bronchoalveolar l avage and roentgenographic appearance in high resolution CT are charac teristic and pathognomonic, and can confirm the diagnosis. The more se vere changes in the elder sib and the radiographic controls suggest th at the pulmonary disease may be progressive in our patients. The descr ibed family of consanguineous, unaffected parents with two affected an d one healthy child confirmed the autosomal recessive inheritance of P AM (McKusick 265100). In addition, the affected girl had autosomal rec essive Waardenburg-anophthalmia syndrome (McKusick 206920), raising th e question of whether this is a chance occurrence or possibly a contig uous gene syndrome.