Anetoderma and borreliosis: is there a pathogenetic relationship?

A 32-year-old man simultaneously developed anetoderma and acrodermatitis chronica atrophicans on his left arm and showed a positive serology for borreliosis with ELISA and Western Blot tests. In addition, a 45 year-old man is presented with anetoderma without any associated systemic or cutaneous diseases, with B. afzelii confirmed as a singular causality through serology (ELISA, Western Blot) and amplification of B. afzelii-specific DNA from the skin by PCR. These two observations highly suggest that anetoderma can be the result of an infection with B. afzelii. We conclude that in patients with anetoderma a serological investigation for Borreliosis should be performed.