Regression of skeletal manifestations of hyperparathyroidism with oral vitamin D.

CONTEXT Parathyroidectomy is the only effective therapy for osteitis fibrosa cystica in hyperparathyroidism. OBJECTIVE The objective of this study was to describe the changes of skeletal and nonskeletal manifestations in a patient with hyperparathyroidism and renal failure after oral vitamin D therapy. DESIGN This was a descriptive case report. SETTING The patient was followed up in a referral center. PATIENT A 55-yr-old male patient with moderate renal failure was referred for expansile lytic lesions affecting several ribs and the spinous process of T12. His creatinine was 1.8 mg/dl; calcium, 8.9 mg/dl; PTH, 666 pg/ml; and 1,25 dihydroxy-vitamin D, 27 pg/ml. Bone mineral density (BMD) Z-scores by dual-energy x-ray absorptiometry were -4.1 at the spine, -1.7 at the hip, and -4.3 at the forearm. MAIN OUTCOME MEASURES The main outcome measures were the skeletal manifestations of hyperparathyroidism. RESULTS At 10 months of therapy, calcium level was 10 mg/d, PTH level declined to 71 pg/ml, and BMD increased by 12% at the spine and 18% at the hip. Computerized tomography (CT) cuts revealed marked regression in the lytic lesions. At 2 yr, BMD increased by an additional 6% at the spine, and there were no further changes in the lytic lesions by CT. The vitamin D receptor genotype using the restriction enzymes Bsm1, Taq1, and Apa1 was Bb, tt, and AA. CONCLUSIONS We showed regression of severe skeletal abnormalities of hyperparathyroidism documented by serial CT images in response to oral vitamin D therapy. It is possible that the vitamin D receptor genotype of the patient modulated this response.