Immune modulation with a staphylococcal preparation in fibromyalgia/chronic fatigue syndrome: relation between antibody levels and clinical improvement.

The aims of this study were to evaluate the serological response to treatment with staphylococcal vaccine in fibromyalgia/chronic fatigue syndrome patients and to explore the relationship between serological response and clinical effect. Twenty-eight patients, half of whom served as controls, were recruited from a 6-month randomised trial in which repeated administration of the staphylococcal toxoid vaccine Staphypan Berna (Berna Biotech, Switzerland) was tested against placebo. Antibody status against extracellular toxins/enzymes, cell-wall components, and enterotoxins was evaluated at baseline and at endpoint. The clinical response to treatment was recorded in rating scales. In the group receiving active treatment, significant serological changes were recorded, whereas no significant changes were found in controls. Treatment led to a significantly increased capacity of serum to neutralise alpha-toxin and a significant increase in serum IgG to alpha-toxin and lipase. Furthermore, the increase in these parameters combined paralleled the improvement in clinical outcome. Thus, the greater the serological response, the greater was the clinical effect. In conclusion, this explorative study has shown that repeated administration of the Staphypan Berna vaccine in patients with fibromyalgia/chronic fatigue syndrome causes a serological response to several staphylococcal antigens, particularly to certain extracellular toxins and enzymes. The results further show that this response is related to the clinical outcome of treatment.