Introduction:

Fibromyalgia (FM) is a non-degenerative syndrome characterized by generalized, chronic musculoskeletal pain, as well as mood, memory and sleep disorders.

Objective:

To search for serum anti-neural antibodies (ANeuA) in patients with FM (FMP) in order to rule out autoimmune etiology.

Methods:

The Fibromyalgia Impact Questionnaire (FIQ) and BECK’s depression inventory (BDI) were applied. Immunorreactivity and the target recognized on the sera from FMPs and healthy subjects were analyzed by indirect immunofluorescence and Western blot.

Results:

Both FIQ and BDI values were significantly altered in FMPs in comparison with those of controls (FIQ, 70 ± 25 vs. 12 ± 12, p < 0.0001; BDI, 17 ± 11 vs. 4 ± 3, p < 0.0002). Only five out of 15 FMP sera had ANeuA specifically directed against neurons from the medial vestibular nucleus of the brainstem. This immunoreactivity was not detected in the sera from the 14 controls. ANeuA recognized a 45 kDa protein.

Conclusions:

30% of FMPs have ANeuA that have not been described before. In future studies, it will be necessary for anti-neural immunoreactivity to be determined in a larger sample and for the role of ANeuAs in the pathophysiology of FM to be established.