Simultaneous measurement of a deficit in total body calcium and phosphorus in diagnosis of hyperparathyroidism.

Simultaneous measurement of a deficit in total body calcium and phosphorus in diagnosis of hyperparathyroidism Bone disease is a well-established complication of primary hyper- parathyroidism but may not be detected early by conventional clinical and radiological procedures because of their limnited sensitivity.'Nevertheless, sequential changes in body calcium estimated by activation analysis in vivo and expressed in relative terms have been reported after parathyroidectomy.3Using an analogous procedure, we have measured the total body content of calcium, phosphorus, sodium, chlorine, potassium, and nitrogen simultaneously in absolute terms (numol or g).4We report a patient in whom an appreciable depletion of calcium and phosphorus was not detected radiologically, and hyperparathyroidism was later confirmed by removal of a parathyroid adenoma.Case report A 62-year-old woman presented with septicaemia and acute renal failure secondary to a right ureteric calculus.Investigations after recovery showed persistently raised serum calcium and alkaline phosphatase concentrations, a renal tubular phosphate leak, and a raised serum parathyroid hormone con- centration of 750 ng/l (normal range 0-550 ng/l).Biochemical findings are