A case with persistent nephrogenic diabetes insipidus following parathyroidectomy for hyperparathyroidism.

A 25-year-old woman with persistent nephrogenic diabetes insipidus (NDI) following parathyroidectomy for primary hyperparathyroidism is described. NDI is a well recognized complication of primary hyperparathyroidism, generally imputed to hypercalcemia, and promptly reversible after correcting it. In our case, the impaired concentrating ability of the renal tubule was irreversible after the removal of the parathyroid adenoma and the correction of the hypercalcemia, presumptively due to the morphological irreversible changes in the kidney. In addition, hypercalciuria persisted and was the cause of a compensatory hyperparathyroidism. Treatment with thiazide diuretic was effective to decrease relative hypercalciuria, thus reversing the compensatory hyperparathyroidism.