The aim of this study is to identify the species of Borrelia involved in the dermatologic manifestations of Lyme borreliosis in France. Indeed, in Europe, as opposed to North America, many bacterial species are involved in Lyme borreliosis. Yet, very few is known about the prevalence and distribution of different bacteriological species that account for the disease in France. Thus, this a nation-wide study in which all French dermatologists are invited to participate. Every adult patient presenting with one of the cutaneous manifestation of Lyme borreliosis: erythema migrans, lymphocytoma or acrodermatitis chronica atrophicans can be included in the study. If the patient agrees participating, after information and written consent, a cutaneous biopsy will be performed in order to isolate Borrelia by means of culture and PCR. An estimated 400 biopsies should be performed within 2 years.

Inclusion criteria:

• Informed adult patient who signed written consent with one the following conditions:
• erythema migrans
• borrelial lymphocytoma
• acrodermatitis chronica atrophicans

Exclusion criteria:

• pregnancy or lactation
• allergy to local anesthesia
• patient who refuses biopsy

Every adult patient presenting with either erythema migrans, borrelial lymphocytoma or acrodermatitis chronica atrophicans