According to a recent study published in Seminars in Arthritis and Rheumatism, the fibromyalgia patients have high prevalence of Small fiber pathology (SPF). The information regarding SFP could be helpful in developing better pharmacotherapies and interventions for the management of fibromyalgia.

Fibromyalgia is a severe neuropathic condition that exhibits widespread chronic pain with neuropathic pain characteristics. The fibromyalgia symptoms exert a significant negative impact on patients' quality of life. Although, the pathophysiology of fibromyalgia is still not clear; evidence regarding the peripheral nervous system with a high SFP prevalence involvement in fibromyalgia is raised — this systematic literature review was intended to confirm the prevalence of SFP among patients with fibromyalgia.

EMBASE, Web of Science, CINAHL, MEDLINE, Cochrane Library and PubMed was searched for the related data. The full-text English language articles with information regarding SFP and fibromyalgia were included. Two independent reviewers screened all articles using a priori criteria. The critical appraisal tool by Munn et al. was used to assess methodological quality and related risk of bias. Random-effects meta-analysis with 95% CI was used to determine overall and subgroup pooled prevalence.

A total of 935 studies were identified; out of which only 8 articles with 222 participants fulfil the criteria. The pooled prevalence of SFP in fibromyalgia during the meta-analysis noticed was 49% with average heterogeneity (I2= 68%). The prevalence rate achieved corneal confocal microscopy was 59%, and by a skin biopsy was 45%. Compelling evidence of a different phenotype comprising SFP in fibromyalgia was observed during the analysis. Overall outcomes showed a high involvement of SFP in fibromyalgia pathophysiology.