NCT06527183

Fibromyalgia and Small Fiber Neuropathy

Fibromyalgia and Small Fiber Neuropathy : Which Prevalence and Which Relationship With Pain ?

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 150 (estimated)
• Sponsor: Hospital Ambroise Paré Paris · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

The primary objective of this study will be to assess the proportion of fibromyalgia patients with diffuse small-fiber neuropathy (i.e. in the upper and lower limbs) and compare this proportion to patients with other chronic pains (nociplastic, nociceptive) and with healthy controls. Our analysis will be based on the demonstration of structural abnormalities of small nerve fibers by means of skin biopsy, but also of functional abnormalities using four validated tests commonly used in this field: quantitative sensory testing (QST), laser evoked potential recordings, Sudoscan and confocal corneal microscopy. It will thus be possible to verify whether or not patients with small fiber neuropathy have a particular clinical profile in terms of pain, physical activity, comorbidities or pain impact.

Detailed description

Small fiber neuropathy has been observed in a large proportion of fibromyalgia patients. However, the pathophysiological role of these neurological abnormalities in determining the pain and other symptoms of fibromyalgia, and the specificity of these abnormalities, are not well understood. The primary objective of this study will be to assess the proportion of fibromyalgia patients with diffuse small-fiber neuropathy (i.e. in the upper and lower limbs) and compare this proportion to patients with other chronic pains (nociplastic, nociceptive) and with healthy controls. Our analysis will be based on the demonstration of structural abnormalities of small nerve fibers by means of skin biopsy, but also of functional abnormalities using four validated tests commonly used in this field: quantitative sensory testing (QST), laser evoked potential recordings, Sudoscan and confocal corneal microscopy. It will thus be possible to verify whether or not patients with small fiber neuropathy have a particular clinical profile in terms of pain, physical activity, comorbidities or pain impact.

Conditions

• Chronic Pain Syndrome

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Skin punch biopsy to demonstrate small fiber neuropathy	Skin punch biopsy to assess intrapidermal nerve fiber density

Timeline

• Start date: 2022-01-04
• Primary completion: 2025-12-01
• Completion: 2026-05-01
• First posted: 2024-07-30
• Last updated: 2025-09-10

Locations

2 sites across 1 country: France