Pregnant Patient on Hemodialysis Who Showed Remarkable Improvement of Severe Hyperparathyroidism by Strict Serum Phosphorus Control.

We encountered a pregnant hemodialysis patient with severe hyperparathyroidism (HPT). Although her disease was considered to be refractory to medical treatment, the serum intact parathyroid hormone (PTH) level remarkably improved without manifestation of hypercalcemia through only strict serum phosphorus control, mainly via intensification of dialysis. The very strong correlation between the serum phosphorus level and serum intact PTH level suggested the possibility of secondary HPT. She ultimately gave birth to a healthy baby. The clinical course of the patient's HPT and the growth of the child have been good for more than six years.