Osteomalacia After Parathyroidectomy in Patients with Uremia

Abstract

Five patients on maintenance dialysis had symptoms of osteomalacia, proven by biopsy, after parathyroidectomy. In all 5 patients clinical and radiographic manifestations of secondary hyperparathyroidism were present before surgery, and in 2 patients preoperative biopsy of bone confirmed the existence of osteitis fibrosa. Like previously described patients with osteomalacia all 5 had multiple fractures and normal or high serum Ca concentrations that rose to abnormally high values on treatment with vitamin D or dihydrotachysterol. Quantitative histomorphometry of biopsy after parathyroidectomy showed no residual parathyroid hormone effect and nearly complete cessation of mineralization. Four patients had forearm autografts of parathyroid tissue that appeared to be functioning at very low rates according to paired venous sampling, and all 5 patients had relatively low circulating concentrations of parathyroid hormone. Secondary hyperparathyroidism may have an important facilitative role in the mineralization of bone in uremic patients.