The Incidence of Hyperparathyroidism in Renal Allograft Recipients with Stable Renal Function

Sung, Yong Jic; Kim, Young Ok; Sung, Kwang Yong; Park, Ju Hyun; Yang, Chul Woo; Kim, Yong Soo; Jang, Yoon Sik; Bang, Byung Kee

Abstract

The hyperparathyroidism which causes renal osteodystrophy is a common complication in patients with end stage renal diseases. It is usually normalized after successful renal transplantation, but it remains in some renal transplant recipients. It is not well known whether hyperparathyroidism decreases bone mineral density in renal allograft recipients or not. To evaluate the incidence and predictive marker for hyperparathyroidism in renal allograft recipients and to describe the impact of hyperparathyroidism on the bone mineral density, we measured intact parathyroid hormone(iPTH) in 193 renal allograft recipients with stable renal and hepatic function. The mean age of patients was 42+/-12(13-76) years old and male female ratio was 1.9. The patients were on pre-transplant dialysis for 14.4+/-15.6(0-130) months and were followed up for 43.8+/-35.7(2-204) months after transplantation. Of the total 193 patients, 13 patients(6.7%) had high iPTH level. All patients showed normal serum calcium and phosphorous levels. iPTH levels were positively correlated to pre- and post-transplant serum alkaline phosphatase levels(vs. pre-transplant r=0.32, P<0.001, vs post- transplant r=0.63, P<0.001). There was no difference in pre- and post-transplant serum calcium, phosphorus, post-transplant serum creatinine and hemoglobin levels between the patients. There were no statistical differences in age, sex, duration of pre-transplant dialysis, duration of post-transplant follow-up, number of transplantation, donor type, primary renal disease and episodes of acute rejection. Of the total 193 patients, bone mineral density was studied in 37 patients. Bone mineral densities did not correlated to iPTH levels. In conclusion, the incidence of hyperparathyroidism in renal allograft recipients with stable renal function was 6.7%. Pre- and post-transplant serum alkaline phosphatase levels might be used as a useful marker for hyperparathyroidism. Serum iPTH level was not correlated to bone mineral density.