Z Gastroenterol 2010; 48 - P5_38
DOI: 10.1055/s-0029-1246583

Reduced Bone Mineral Density in Wilson Disease

KH Weiss 1, D Gotthardt 2, E Ullrich 1, U Merle 1, W Stremmel 1
  • 1Abt. Innere Medizin IV, Universitätsklinikum Heidelberg, Heidelberg
  • 2Medizinische Klinik IV, Universität Heidelberg, Heidelberg

Introduction:

Wilson disease (WD) is an inherited disorder of human copper metabolism. Remarkable findings in WD are various skeletal changes including demineralization, subarticular cysts, and marginal fragmentation, which have been reported in Wilson disease ranging from mild to severe. Recent studies suggested a high prevalence of osteoporosis up to 43% to 68%. Risk factors for the development of osteoporosis in WD are unknown.

Patients and Results:

This study concerns 151 patients examined at the University Heidelberg between 1990 and 2009. Bone mineral density (BMD) measurements were performed at presentation and at routine follow-up examinations. Overall prevalence of osteopenia and osteoporosis was 79/151 (52.3%) and 15/151 (9.9%), respectively. No statistically significant differences were found when patients were grouped by manifestation, sex, WD treatment, presence of liver cirrhosis or mobility. Patients with the most common ATP7B-mutation H1069Q showed a trend to higher bone mineral content than other genotypes.

Serum parameters of calcium metabolism were compared amoung patients with normal bone mass, osteopenia and osteoporosis. Statistically significant differences were observed for PTH only, as patients with osteoporosis had significant higher median PTH levels (median 5.9 pmol/l vs. 3.9 pmol/l), p=0.001.

During follow-up, 42 patients with osteopenia received vitamine D/ calcium supplementation. 3 of these patients improved in BMD, 4 progressed to osteoporosis and 35 presented unchanged. Only 1 of 9 osteoporotic patients improved under bisphosphonate therapy.

Discussion:

Bone mineral density in WD was at least in part correlated with the ATP7B genotype suggesting an intrinsic effect of the WD-mutation in the pathogenesis. The outcome of prophylactic (vitamine D/calcium) or therapeutic (bisphosphonates) therapy was disappointing. Here, correction of a mild hyperparathyroidism might represent a more promissing approach.

ATP7B - Osteoporosis - WILSON DISEASE - bone mineral density