Vitamin D resistant rickets.

Vitamin D resistant rickets is not a rare disorder. Increased awareness of this metabolic disorder during the examination of children with bowed legs, even infants receiving normal supplements of vitamin D, may lead to diagnosis oftener. Ten previously unrecorded cases of this disorder are included within this report. Three of the patients had associated congenital anomalies which also required treatment. Treatment of the vitamin D resistant rickets consists of the oral administration of large doses of vitamin D. Careful observation of patients during vitamin D therapy to prevent overdosage and resultant hypercalcemia is of utmost importance. Surgical correction of the bony deformities is rarely necessary. The cause of vitamin D resistant rickets is thought to be a defect of renal tubular mechanisms.