Aim: To assess the levels of hyaluronic acid (HA) in Danish patients with fibromyalgia (FM).
Methods: Serum levels of HA were determined in 53 patients with established FM and 55 control samples with a radiometric assay (Pharmacia). Values were correlated to clinical parameters of disease severity (duration of disease, tender point scales, visual analogue scales).
Results: There were no differences in the HA levels of patients and controls. In all the patients, except one, values were within the reference intervals. Nor was there an association between HA levels and clinical findings.
Conclusions: Patients with FM do not generally have increased serum levels of HA, and other serum measurements have not been helpful in the diagnosis of FM. Some biochemical changes have been described in FM, however, and these have mainly been observed in the spinal fluid.