Idiopathic arterial calcification of infancy.

We describe two twin sisters in whom calcification of different arteries was detected in the first weeks of life. Transient renal insufficiency, arterial hypertension, and skeletal abnormalities were also observed. One child had anasarca and heart decompensation at birth. Prenatal infarction of one kidney had occurred in the same infant. A kidney biopsy showed calcium deposits in all the layers of the arteries. Most findings in these patients are compatible with idiopathic arterial calcification of infancy (IACI). Investigation of calcium and phosphorus metabolism revealed spontaneously receding hypercalciuria, increased intraerythrocytic calcium levels, and transient X-ray abnormalities of the long bones. Treatment initially consisted of biphosphonate and later, the calcium antagonist flunarizin. A progressive diminution of the arterial calcification was observed in the course of both treatments.