Clinical, Electrophysiological and Genetic Characteristics of Hereditary and Inflammatory Polyneuropathies in France

To describe the clinical, electrophysiological, and genetic characteristics of genetic and inflammatory peripheral neuropathies in detail in order to advance our understanding of these rare and disabling diseases. This detailed description is also necessary with a view to the future use of innovative treatments. In recent years, there have indeed been spectacular advances in the field of genetic therapies (siRNA, antisense oligonucleotides, gene therapy) and next-generation immunosuppressive therapies (complement inhibitors, anti-FcRN), all of which are applicable in the short- to medium-term for genetic and inflammatory polyneuropathies.

This is a multicenter, prospective-retrospective study using data collected as part of routine clinical care.The objectives are as follows:

* Describe the different subtypes of genetic and inflammatory pyneuropathies in France
* Describe the demographic characteristics
* Describe the geographic distribution
* Describe the electrophysiological findings
* Describe the genetic abnormalities

Primary outcomes

• Number and percentage of participants by type of polyneuropathy [At inclusion, based on the diagnosis documented in the medical record.]: Participants will be classified as having genetic or inflammatory polyneuropathy according to the diagnosis documented in their medical records. The number and percentage of participants in each category will be reported.

Secondary outcomes

• Number and percentage of participants by polyneuropathy subtype [At inclusion, based on the diagnosis documented in the medical record.]: The number and percentage of participants in each genetic or inflammatory polyneuropathy subtype, as documented in the medical records, will be reported.
• Demographic characteristics of patients [At baseline, corresponding to the date of inclusion in the study, using data available in the medical record up to that date.]: Description of demographic characteristics of patients with genetic or inflammatory polyneuropathies, including age, sex and other available demographic data.
• Geographical distribution of patients [At baseline, corresponding to the date of inclusion in the study, using data available in the medical record up to that date.]: Description of the geographical distribution of patients with genetic or inflammatory polyneuropathies included in participating centers in France.
• Number and percentage of participants by electrophysiological neuropathy pattern [At inclusion, based on electrophysiological examinations available in the medical record.]: The electrophysiological neuropathy pattern documented in the medical record will be classified as axonal, demyelinating or mixed. The number and percentage of participants in each category will be reported.
• Genetic abnormalities [At baseline, corresponding to the date of inclusion in the study, using genetic data available in the medical record up to that date.]: Description of genetic abnormalities identified in patients with genetic or inflammatory polyneuropathies, when genetic analysis results are available in the medical records.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Adult patients aged 18 years or older.
* Patients with a diagnosis of genetic or inflammatory polyneuropathy, confirmed by complementary examinations performed as part of routine care, including genetic, biological and/or electrophysiological tests.

Exclusion Criteria:

\- Patient opposition to the use of their routine care data for research purposes.