1 University of Oviedo and Hospital de la Seguridad Social, Oviedo, Asturias, Spain
2 Department of Pediatrics, Medical College of Virginia and Children's Medical Center, Virginia Commonwealth University, Richmond
Idiopathic hypoparathyroidism is a rare entity which is clinically characterized by episodes of hypocalcemia and hyperphosphatemia with deficient endogenous parathyroid hormone secretion.1,2 Exogenous parathyroid hormone administration elicits the appropriate renal phosphaturic response,3,4 and no associated endocrinopathies have been reported.1,2 Treatment with 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) is currently recommended.1,2,5
Responses to exogenous parathyroid hormone infusion consist not only of an increase in urine phosphate excretion but, more definitively, an increase in nephrogenous cyclic adenosine monophosphate (cAMP) production.6 Studies of these parameters in pediatric patients have been reported,3 but little is known about the influence of parathyroid hormone administration on the urine calcium excretion of hypoparathyroidism in children and how the renal response to parathyroid hormone may be modified by the 1,25-(OH)2D3 therapy.