Pseudohypoparathyroidism type II and anticonvulsant rickets.

A patient treated with anticonvulsants showed hypocalcemia and hyperphosphatemia in association with increased serum parathyroid hormone, reduced serum 25-hydroxy D3, diminished response in phosphorus excretion to exogenous parathyroid hormone and normal response in cyclic AMP excretion. Oral administration of Vitamin D3 resulted in normalization of serum 25-hydroxy D3, calcium, and phosphorus. At this stage, phosphorus excretion after parathyroid hormone returned to normal. These findings suggest that the patient had pseudohypoparathyroidism type II with anti-convulsant medication as a complicating factor.