Sensory neuronopathies (SN) are a group of rare neuropathies characterized by selective destruction of sensory neurons located in the dorsal root ganglia. SN may result from a wide range of etiologies, particularly paraneoplastic, autoimmune, toxic, and genetic causes. The functional prognosis of patients with SN is generally poor: in a recent study, two-thirds of patients had a modified Rankin Scale (mRS) score ≥3 and nearly half had an mRS ≥4.

The absence of reliable biomarkers in neuropathies justifies the use of clinical scales as indicators of disease severity, disability, and treatment response. However, none of the currently available "general neuropathy" scales have been specifically designed or validated for SN. The only scale developed specifically for SN is the SEARS (Sensory Ataxia Rating Scale), proposed in 2019, but it has not been widely used nor validated in large populations.

As a result, the absence of a clinical scale specifically designed for patients with SN makes longitudinal follow-up more challenging, particularly when assessing the response to immunomodulatory or immunosuppressive treatments when these therapies are indicated.

Inclusion Criteria:

• Patient affiliated with or beneficiary of a social security system
• Patient having received appropriate study information
• Adult patient ≥18 years old, male or female
• Patient diagnosed with probable SN according to Camdessanché et al. diagnostic criteria
• SN with one of the following etiologies:

Paraneoplastic SN with anti-Hu or anti-CV2/CRMP5 antibodies SN associated with Sjögren's syndrome, systemic lupus erythematosus, or primary biliary cholangitis Platinum-salt-induced SN SN caused by CANVAS syndrome

Exclusion Criteria:

• Patient unable to understand or read French

• Patient refusal to participate

• Patient known to have another neuropathy phenotype and/or etiology that could significantly influence clinical scales and electrophysiological parameters, including:

  • Diabetes mellitus
  • Significant alcohol consumption
  • Severe chronic kidney disease (GFR <30 ml/min)
  • Vitamin B12 and/or vitamin E deficiency
  • Vitamin B6 excess
  • Chemotherapy other than platinum salts
  • HIV infection