Disorders of calcium and phosphorus metabolism after successful kidney transplantation.

Systematic study undertaken of 44 transplant patients with plasma creatinine below 0.11 mmol/L indicated renal phosphorus leak in approximately two-thirds of them and increased plasma PTH in all but one. Plasma 1,25(OH)2D was elevated in half the patients in whom it was measured. The lack of correlation found between plasma 1,25(OH)2D and plasma PTH or phosphorus probably indicates tubular lesions resulting in decreased production of 1,25(OH)2D. A phosphorus restriction test in 12 hypophosphatemic patients demonstrated that the reduced renal phosphorus reabsorption probably was due to both persisting hyperparathyroidism and a PTH-independent phosphorus leak.