Possible Association Between Anti-Trisulfated-Heparin- Disaccharide Immunoglobulin M Autoantibody and Fibromyalgia Syndrome

Background: Fibromyalgia syndrome (FMS) is estimated to affect 2-4% of the general population. While FMS has some known environmental and genetic risk factors, the disorder has no clear etiology. A common coexisting disorder with FMS is small fiber neuropathy (SFN). High levels of serum Immunoglobulin M (IgM) binding to trisulfated-heparin-disaccharide (TS-HDS) were recently found to be associated with SFN. Objectives: To evaluate potential differences in anti-TS-HDS an-tibody titers in women with FMS compared to healthy controls. Methods: In this cross-sectional study, we evaluated 51 female participants: 30 with a diagnosis of FMS and 21 healthy controls who had been recruited at the Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Israel. All of the participants were older than 18 years of age. Anti-TS-HDS IgM levels were measured in their sera using the enzyme immuno-assay technique. Results: The mean anti-TS-HDS IgM levels were significantly lower in the FMS group, compared with the control group (7.7 +/- 5 vs. 13.2 +/- 8.6 U/ml, respectively; P = 0.013). Conclusions: There is a possible association between FMS and anti-TS-HDS IgM. This association might be the missing link for the coexistence of SFN and FMS, but further study should be performed to assess this association and this auto-antibodycharacteristic.