Recruiting NCT06527183

Fibromyalgia and Small Fiber Neuropathy

— Observational Chronic Pain Syndrome

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied: The protocol lists: Skin punch biopsy to demonstrate small fiber neuropathy.
Who it may be relevant to: Registry conditions: Chronic Pain Syndrome. Basic parameters: from 18 years · All.
What needs checking: Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place: France
Next step: Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

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Official title

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

Overview

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.

Interventions

Diagnostic test Skin punch biopsy to demonstrate small fiber neuropathy
Skin punch biopsy to assess intrapidermal nerve fiber density

Primary outcome measures

Prevalence of small fiber neuropathy or pathology as assessed with skin punch biopsy in patients with fibromyalgia as compared to patients with other chronic pains and healthy subjects [Time frame: Baseline and at 6 months]

Secondary outcome measures (5)

Correlation between intraepidermal nerve fiber density and pain or other patient reported outcome measures (quality of life, distress, disability...) [Time frame: Baseline and at 6 months]
Investigate the potential specificity of the results obtained by comparing them with pain patients without fibromyalgia or nerve damage (patients with any nociceptive or nociplastic pain without fibromyalgia) matched for age and gender [Time frame: Baseline and at 6 months]
Monitor the evolution of abnormalities obtained over time (6 months) and correlate them with the evolution of pain and associated symptoms. [Time frame: 6 months]
Determine the sensitivity and diagnostic value of corneal confocal microscopy and laser evoked potentials as compared with skin punch biopsy for exploring nociceptive fibers [Time frame: Baseline and at 6 months]
Determine the diagnostic value of the sudoscan and quantified sensory tests compared with other tests for exploring nociceptive fibers in these patients [Time frame: Baseline and at 6 months]

Eligibility criteria

Inclusion criteria

patients over 18 years of age with no age limit -
having given their signed consent to take part in the study
affiliated to the French social security system
able to be followed for the entire duration of the study
reading and understanding French
accepting the principle of the study and able to comply with its conditions
suffering from chronic pain for at least six months of at least moderate intensity (≥ 4/10)
fibromyalgia detected by the FiRST questionnare and defined by the revised diagnostic criteria of the WHO or chronic nociceptive or nociplastic pain without associated fibromyalgia.
chronic pain for at least 6 months of at least moderate intensity (≥ 4/10)
untreated or with stable analgesic treatment for at least 2 weeks prior to inclusion- normal neurological examination at inclusion

Exclusion criteria

litigation or compensation-seeking
cancer for less than 2 years
known cause of small-fiber neuropathy such as diabetes, systemic disease, hypothyroidism, alcohol, renal failure, genetic disease
clinical or EMG neuropathy
peripheral or central nervous system pathology with or without associated neuropathic pain
uncontrolled chronic pathology such as : morbid obesity, sleep apnea, uncontrolled hypertension, etc. - psychosis, previous suicide attempt
drug or psychoactive substance abuse
cognitive or psychological disorders incompatible with compliance with and/or understanding of the protocol
participation in another biomedical research protocol.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model: Case-control

Study locations

France · 2 centers

Inserm U987 — Boulogne-Billancourt
Centre d'Evaluation et de Traitement de la douleur — Paris

Identifiers

NCT: NCT06527183 · 2020-A03400-39

Primary sources (government registries)

ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗