Is glucocorticoid-induced osteonecrosis after kidney transplantation related to osteoporosis?

Abstract

Osteopenia and osteonecrosis (ON) cause important longterm morbidity in renal transplant (Tx) recipients with increasing incidences because of longer graft survival and related drug exposure. A 38-year-old woman who started on haemodialysis in November 2001 had a renal Tx from a live relative in March 2003 due to chronic pyelonephritis with vesicoureteral reflux related end-stage renal disease. She had persistent secondary amenorrhoea 2 months before dialysis treatment. Throughout this period she had calcitriol and phosphorus binders for controlling secondary hyperparathyroidism. Her pre-Tx serum parathyroid hormone (PTH) was 73.2 pg/ml and body mass index (BMI) was 18.4 kg/m2 . Post-Tx immunosuppressive treatment was prednisolone (500 mg initially, then 30 mg/day), tapered to 25 mg/day by postoperative day 14, mycophenolate mofetil (2 g/day), cyclosporin (CsA; 100 mg/d) and daclizumab (a dose of 1 mg/kg, totalling five dosages with 2-week intervals). After an uneventful 4 weeks she complained of severe leg pain and symptoms of muscle weakness in the previous 4 days. The dose of prednisolone was tapered to 15 mg/day, but pain developed in both shoulders. Diffuse ON was diagnosed by hip and shoulder magnetic resonance imagings (MRI). At the time of diagnosis the total cumulative doses of prednisolone and CsA were 1220 mg and 2925 mg in 4 weeks, respectively. Serum creatinine was 0.7 mg/dl, calcium 10.5 mg/dl, Alkaline phosphatase (ALP) 271 IU/l, PTH 84 pg/ml, calcitonin 27 pg/ml and calcitriol 22.9 ng/dl. Bone mineral densities (BMD) of the lumbar spine and the hip region by Dual x-ray absorptiomtery (DEXA) after post-Tx 8 weeks were evaluated as osteoporosis with T scores of 3.2 and 3.9, respectively. Oral calcium, calcitriol and alendronate were added to the treatment. Her complaints regressed within 10 days. The dose of prednisolone was tapered to 10 mg/day at month 4 and to 5 mg/day at month 10. One year later, hip and shoulder MRIs showed normal findings. The respective post-Tx T scores of the lumbar spine and the femoral neck improved from -2.8 and -3.5 in the first year to -2.4 and -2.2 in the second year. Her serum creatinine level was 0.8 mg/dl with no complaint.