PP03.17 – 2750: Bone turnover and its connection to penicillamine use in Chinese patients with Wilson disease

Abstract

Objective The prevalence of osteoporosis is higher among patients with Wilson disease (WD) than the general public, of which the cause is still unclear. The purpose of this research is to analyze the possible causes for the high prevalence and connection between penicillamine and bone mineral density. Methods Eight-four WD patients (44 males and 40 females) and 76 controls (27 males and 49 females) were enrolled in this study. The patients were diagnosed via mutation analysis of ATP7B. Dual-energy X-ray Analysis (DXA) was used to evaluate the bone mineral density (BMD). Serum phosphate, calcium, magnesium, parathyroid hormone, calcitonin, osteocalcin, 25-(OH)-Vitamin D as well as alkaline phosphatase were measured to evaluate the bone turnover activity. Based on the information on imaging, laboratory test and previous medical history, we analyzed the correlations between BMD, bone turnover activity and patients' age, gender, clinical manifestations and maximum dosage of penicillamine. Results Fifty-eight patients received a DXA scan. The prevalence of osteoporosis in WD patients was 27.58% (16/58) whereas that in the controls was 19.74% (15/76). BMD, T. score and Z score of lumbar vertebrae as well as BMD, Z score of hip neck were significantly lower in WD patients. 25(OH)-Vitamin D, serum phosphate, serum calcium and ALP were significantly higher in WD patients than the controls. But among patients who have received different maximum daily dosage of penicillamine, larger dose was associated with lower BMD. Age, gender and clinical manifestations did not affect BMD among WD patients. Conclusion WD patients have a higher prevalence of osteoporosis, lower BMD and higher bone turnover activity compared with controls. The use of penicillamine is an important precipitating factor.