Paradoxical relation of osteopetrosis and rickets

Abstract

A 2-month-old boy was presented with fever and restlessness. He was the third child of consanguineous parents and born after a full-term uncomplicated pregnancy. His older brother had been diagnosed as osteopetrosis and died when he was 2 years old. In laboratory findings his hemoglobin was 6.3 gr/dL, white blood count 4150/mm3, platelet count 120.000/mm3, calcium level was 6.1 mg/dL, phosphorus 2.9 mg/dL and alkaline phosphatase 1398 IU/L. Parathormone level was high (295 pg/mL), urine Ca/cre (0.2) was significantly decreased with normal 25 hydroxyvitamin D level. Examinatin of bones revealed generalized increased bone density, cupping of the distal epiphyses in the radius and ulnae. Radiographic and laboratory findings were compatible with osteopetrosis and rickets. He had seizure because of hypocalcemia. 2000 IU (low dose) vitamin D was given for one week period with parenteral calcium gluconat (100 mg/kg/dose) and thereafter 400 IU vitamin D was continued daily. After treatment of low dose-short period vitamin D, hypocalcemia improved, and secondary calcification was shown in ulnae by X-Ray.