Response Profiles to High-concentration Capsaicin Desensitization in Patients with Peripheral Neuropathic Pain with or Without Allodynia: a Regional Multicenter Prospective Cohort

Inclusion Criteria:

• Patient over 18 years of age on the day of inclusion

• Patient who has been informed and has not expressed opposition to participating inthe study,

• Patient with peripheral neuropathic pain (whatever the etiology), defined by :

• "Neuropathic Pain 4" score ("DN4" score) ≥ 4/10

• AND pain according to the numerical scale (EN) > 4/10,

• AND stable analgesic treatment for at least 1 month,

• AND with or without mechanical allodynia according to the Quantitative SensoryTesting (QST) : Brush test (dynamic), Von Frey test (static)

• AND with or without thermal allodynia to hot or cold as determined by aROLLTEMP-II® (Rolltemp is a device designed for quick screening of temperaturesensibility over large body areas).

• Patient responding to an indication of desensitization to high concentrationcapsaicin concentration and not presenting any contra-indication.

• Patient naïve of high concentration of Capsaicin on the concerned zone

• Patient understanding French

Non-inclusion Criteria:

• Patient with pain related to complex regional pain syndrome (criteria not meetingthe indication for capsaicin)

• Patient with active cancer (underlying disease and treatments may modify painperception),

• Patient receiving or having received in the last 3 months Botulinum toxin A on theconcerned area (this treatment of neuropathic pain may modulate the effect ofcapsaicin and disturb the demonstration of causality),

• Patient with planned surgery within the next 12 months on the painful site (surgerymay cause neuropathic damage and/or bias the pain assessment),

• Patient included in an interventional research protocol,

• Patient under guardianship or curators,

• Patient under legal protection

Exclusion Criteria:

None