Alterations in bone metabolism and HLA B27

S. Schmidt and colleagues presented a study on HLA B27 as a possible risk marker for altered bone metabolism in patients with spondyloarthritis and uveitis without spondyloarthritis as well as healthy carriers of HLA B27. The Wnt antagonists dickkopf 1 (DKK1) and sclerostin were measured. The authors didn’t speculate on osteoporosis, which could be interesting as the levels of healthy carriers are also alterated. Wikipedia: “Currently an anti-sclerostin antibody for the treatment of osteoporosis is being co-developed by Amgen and UCB.” (Paszty C, Turner CH, Robinson MK (September 2010). "Sclerostin: a gem from the genome leads to bone-building antibodies". J. Bone Miner. Res. 25 (9): 1897–904. doi:10.1002/jbmr.161. PMID 20564241) The autors concluded: „These data suggest that alterations in bone metabolism even occur in the absence of clinical SPA and are associated with HLA-B27 carriage.” I think that there is potential for new developments as well as a need to further evaluate these biomarkers in ankylosing spondylitis.

Abstract No. 594
Evidence of Human Leucozyte Antigen-B27 in Healthy Individuals and Patients with Uveitis Is a Risk Factor for Alterations in Bone Metabolism.
Sarah Schmidt1, Stephanie Finzel1, Jürgen Rech1, Matthias Englbrecht1, Silke Winkler1, Isabel Schmidt1, Roula Said-Nahal2, Maxime A. Breban2 and Georg A. Schett3.
1University of Erlangen-Nuremberg, Erlangen, Germany, 2Ambroise Pare’ Hospital (AP-HP), and Versailles Saint Quentin en Yvelines University, Boulogne-Billancourt, France, 3Department of Internal Medicine III and Institute for Clinical Immunology, University of Erlangen-Nuremberg, Erlangen, Germany
Conclusion: HLA-B27 positivity is associated with low levels of DKK1 and sclerostin independent from the presence of clinical symptoms of SPA. Both HLA-B27 healthy carriers as well as HLA-B27 associated uveitis without SPA Sunday, show lower levels of these two Wnt antagonists than normal HLA-B27 negative controls. These data suggest that alterations in bone metabolism even occur in the absence of clinical SPA and are associated with HLA-B27 carriage.

11.08.2016:

In the meantime Gamsjaeger and colleagues tested transgenic HLA B27 rats, which have a lower mineral/matrix ratio, higher relative proteoglycan, advanced glycation end content and pyridinoline/divalent collagen cross-link ratio, when compared with wild type animals. Therefore they conclude, that this model could be a useful for studies on the pathophysiology of spondyloarthropathy and of pharmacological intervention. 

http://www.ncbi.nlm.nih.gov/pubmed/24771481

 

Rheumatoid arthritis and falls

The study of C. Boehler and colleagues tried to correlate disease activity of rheumatoid arthritis and falls (Abstract: http://www.ncbi.nlm.nih.gov/pubmed/22879462). “Conclusion: The strongest correlation with falls was evident for patient-reported outcomes. Pain seems to be the common ground of these parameters.”
As falls should be avoided, this study suggests an increased attention towards the risk of falling. Patients with a higher level of disease activity are at a higher risk of falling. Pain seems to play a pivotal role. So control of pain and disease activity may reduce the risk. Concomitant osteoporosis is also of interest, but this issue hasn’t been addressed in the study. Also physiotherapy and especially muscle building exercise may be helpful in preventing falls.