Vitamin D3 metabolites in hypercalcaemic adults after kidney transplantation.

Vitamin D3 metabolites and iPTH were measured in 26 patients at various times after renal transplantation. Hypercalcaemia (serum Ca greater than 2.62 mmol/L, 14 patients) was associated with hyperparathyroidism (p less than 0.02) and raised 1,25(OH)2D3 (p less than 0.05) but raised 1,25(OH)2D3 was also found in most patients in the normocalcaemic group. Lower 25(OH)D3 concentrations were found in the group with normal 1,25(OH)2D3 compared to the group with elevated 1,25(OH)2D3 (p less than 0.05). Low values of 24,25(OH)2D3 were found in both the normocalcaemic and hypercalcaemic patients (p less than 0.002). Impaired creatinine clearance (less than or equal to 55 ml/min, mean: 38 ml/min) was not associated with reduced 1,25(OH)2D3. No difference in D3 metabolites was found between hypophosphataemic and normophosphataemic patients.