Persistent hyperparathyroidism following renal transplantation is not uncommon, however the ideal management requires careful consideration of multiple pre- and post-transplant factors. We present a case of 56 year old woman with end stage renal failure secondary to autosomal dominant polycystic kidney disease. Her background is significant for left breast carcinoma, mitral valve repair and congenital hearing impairment.
Prior to renal transplantation, she required haemodialysis for 6 years. She had an elevated parathyroid hormone (PTH) of 127pmol/L with normocalcemia and mild hyperphosphatemia of 1.09mmol/L, normal 25-hydroxyvitamin D and low 1,25hydroxyvitamin D of 28pmol/L, consistent with end stage renal disease. Markers of bone formation were elevated with raised alkaline phosphatase (ALP) of 120U/L and procollagen type 1 N-terminal propeptide (P1NP) 515mcg/L (normal range 15-70), and elevated bone resorption with high β-C-terminal telopeptide of type 1 collagen (β-CTX) of 2.08mcg/L (normal range <0.58). Her bone mineral density (BMD) measured by dual energy x-ray absorptiometry was in the osteoporotic range, with a lumbar spine T-score -3.6, total hip T-score -3.0, 1/3 radius T-score -3.1 and ultra-distal radius T-score -4.4. She had no fractures. She was treated with calcitriol 0.25mcg daily.
Following cadaveric transplantation, she had persistent hyperparathyroidism. A parathyroid sestamibi scan was suggestive of a right inferior parathyroid adenoma (concordant ultrasound). She was commenced on risdedronate 35mg weekly. At one year post-transplant, on prednisone 5mg daily, her BMD was stable/improved, with a lumbar spine T-score -3.7, total hip T-score -2.6 and 1/3 radius T-score -2.9. Bone turnover was in the mid-normal pre-menopausal range with P1NP 38mcg/L, β-CTX 19mcg/L and ALP 71U/L. She had persistent hyperparathyroidism, with a PTH of 35pmol/L, corrected calcium 2.75mmol/L, phosphate 0.83mmol/L, 25hydroxyvitamin D 46nmol/L and 1,25hydroxyvitamin D 188pmol/L.
We present the available management options for this patient in light of competing factors and the current evidence.