Osteoscintigraphic changes in kidney-transplanted patients

Metabolism of prednisone in kidney transplanted patients with necrosis of the femoral head

Interindividual variation of the metabolism of prednisolone and of the susceptibility to glucocorticoids might be possible factors contributing to the development of osteonecrosis after renal allotransplantation. As this aspect has not been properly investigated previously, we compared, in the present study, the metabolism of total and free prednisolone in 6 renal allotransplanted patients who subsequently developed osteonecrosis of the femoral head and the metabolism of 6 matched controls, who did not develop osteonecrosis. There was no difference in age, bodyweight, total serum protein or albumin, or in liver or renal function. The baseline cortisol was 54 +/- 23 micrograms in patients with necrosis, and 102 +/- 53 micrograms/l in patients without necrosis (n.s.). Likewise there was no difference in the peak concentration of prednisolone (420 +/- 43 vs. 394 +/- 42 micrograms/l, n.s.), the bioavailability (0.57 +/- 0.09 vs. 0.61 +/- 0.05, n.s.) or in the apparent volume of distribution at steady state (Vdss, 0.37 +/- 0.09 vs. 0.37 +/- 0.04 l/kg, n.s.). The clearance of prednisolone in patients with osteonecrosis was 33% lower (0.79 +/- 0.11 vs. 1.18 +/- 0.13 ml/min./kg b.wt., P < 0.05) and t1/2 was correspondingly 33% longer (246 +/- 18 min. vs. 184 +/- 15 min., P < 0.05) than in patients without osteonecrosis. However, there was no difference in the apparent volume of distribution of free prednisolone (2.07 +/- 0.36 vs. 1.69 +/- 0.28 l/kg, n.s.), in the t1/2 (152 +/- 30 vs. 107 +/- 20 min., n.s.), or in the clearance (7.33 +/- 2.12 vs. 7.82 +/- 1.18 ml/min./kg) between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Necrosis of the femoral head after renal transplantation

The cumulated risk of developing necrosis of the femoral head following renal transplantation was 42/374 in patients treated with steroids and azathioprine, and 4/124 in patients treated with cyclosporine-A and a reduced dose of steroids. 29 of the osteonecrosis cases were bilateral, with the time lapse between the two sides rarely exceeding 6 months. The reduction in the rate of osteonecrosis paralleled a reduction in the number of rejection episodes during the first month after transplantation and in the cumulated dose of steroids 1 month and 1 year after transplantation. We concluded that the risk of femoral head necrosis following renal transplantation is reduced by using cyclosporin-A for immunosuppression, which caused less rejection episodes and consequently a reduction in steroid medication.

Osteonecrosis in renal transplant recipients. Early radiological detection and course

Early radiologic signs and the radiologic course were examined retrospectively in 20 renal transplant patients who developed osteonecrosis after transplantation. Osteonecrosis appeared in 25 hips, 8 knees, 9 shoulders and 1 elbow. In most patients who developed osteonecrosis of the hip the early radiologic signs of osteonecrosis, with areas of lucencies and increased densities, were preceded by a thin fracture line in the immediate subchondral bone, parallel to the articular surface, appearing within a mean of 14 months after renal transplantation. This change seems to be a specific and very early finding in patients who subsequently develop osteonecrosis after renal transplantation. The initiation of collapsing phenomena of the articular surface was preceded by architectural changes near the articular surface wtih areas of lucencies and sclerosis. At the time of this investigation 26 per cent of the bones showed signs of regression of the changes with rebuilding of the former shape; 32 per cent showed progression and in 42 per cent the condition was stationary.