Metastatic pulmonary calcification in a dialysis patient

Pulmonary metastatic calcification associated with uremic patients is a complication of hyperparatiroidism characterized by deposits of calcium salts in alveolar walls, generally slowly progressive and often asymptomatic. We describe a patient undergoing long-term hemodialysis with severe secondary hyperparathyroidism, pulmonary infiltrates of calcium density of chest-x-ray, abnormal pulmonary diffusing capacity and positive technetium 99m diphosphonate (99m Tc-DPN) lung scan. Bacteriologic studies in bronchoalveolar lavage were negative. Lung biopsy showed diffuse septal calcification with fibrosis and immunofluorescence was negative. The evolution was unfavorable despite treatment. We review physiological, clinical, diagnostic and therapeutic aspects in order to a better understand this illness.