In Reply.—It was very interesting to read about four of five children in a family who had pseudohypoparathyroidism and eventually seemed to develop pseudo-pseudohypoparathyroidism.
Our patient had normal levels of calcium and serum inorganic phosphate on several occasions, unlike your patient who had a high level of serum inorganic phosphate. Hypocalcemia and hyperphosphatemia are characteristic of patients with pseudohypoparathyroidism. A complication, particularly of hyperphosphatemia, is the frequent occurrence of soft tissue calcifications. In pseudohypoparathyroidism, the mineral deposits in ectopic sites may include the development of true bone.1 Lack of these findings is consistent with normal levels of serum inorganic phosphate levels in our patient.
Our patient failed to show phosphaturic response to parathyroid hormone administration. Bell et al2 have demonstrated that higher doses of parathyroid hormone did cause a rise in serum and urinary calcium levels and in urinary phosphate excretion in patients with pseudohypoparathyroidism. However, the