Clinical, biochemical and radiological characterization of Van Buchem disease
A follow-up study

The rare sclerosing bone disorder Van Buchem Disease (VBD) is caused by a
defective synthesis of the protein sclerostin. Sclerostin antagonises Wnt
signalling in osteoblast, thereby down regulating bone formation. In VBD the
decreased expression of sclerostin therefore leads to generalised hyperostosis.
Due to the rarity of the disorder, literature about VBD is sparse, with only a
few studies, examining small numbers of patients. A more complete
characterization of this rare disorder should not only give better insight in
its etiology and pathology, but can also lead to a better understanding of the
working mechanism of sclerostin and its effect on bone formation.
In 2013 we reported the first cross-sectional systematic study of patients with
VBD and their heterozygous disease-carriers. Our data suggested that the
clinical complications of the disease stabilize with time raising the question
whether sclerostin controls bone formation to the same extent throughout life.
However, longitudinal data to test this hypothesis are not available either in
patients with VBD or in those with the closely related disease sclerosteosis
that is due to loss-of-function mutations of the SOST gene. In the present
study we will test this hypothesis 8 years after the original evaluation, with
specific aim to characterize their clinical, biochemical and densitometric
changes with aging.

Clinical, biochemical and radiological characterization of Van Buchem Disease

Follow up study

subjects will be asked for disease related complains, 2-3 tubes of blood will
be obtained from each subject, and bone mineral density will be determined by
DEXA scan.