Clinical Research Directory

Inclusion Criteria: * Age ≥ 18 years * Subject informed of the results of the prior medical examination * Subject informed about the objectives, procedures, and potential risks of the study * Subject affiliated with a health insurance/social security scheme (beneficiary or dependent) * Subject having provided dated and signed informed consent * Lyme borreliosis/acrordermatitis chronica atrophicans (ACA) group: Subject presenting clinical and biological criteria or Borrelia identification confirming chronic atrophic acrodermatitis, with appropriate antibiotic treatment initiated less than 18 months ago or untreated • Control group: Healthy subject with no history of Lyme disease and negative Lyme serology Exclusion Criteria: * Body weight \< 50 kg * Pregnancy or breastfeeding * Diabetes mellitus * Immunodeficiency or ongoing immunosuppressive treatment (including oral corticosteroids) * Contraindication to local anesthesia with lidocaine, with or without adrenaline * Inability to provide informed consent (emergency situation, inability to understand study information, …) * Participation in another clinical trial * Legal protection measures (guardianship, curatorship, or legal safeguard)