In the present study, we report the occurrence of borreliosis in patients from the Brazilian Amazonic region. Nineteen (7.2%) out of 270 dermatological patients with different skin diseases (no one with clinical
Lyme disease), tested positive by ELISA for Borrelia burgdorferi. Serum samples from 15 out of the 19 ELISA-positive patients were further evaluated by Western blot. Presence of Borrelia burgdorferi specific IgG was confirmed in eight (53.3%) out of the 15 patients. All eight patients with ELISA and Western blot positive reactions were treated with doxycycline, according to the Centers for
Disease Control and Prevention guidelines. One of them had clinical manifestations of colagenosis and was sent to the Department of Internal Medicine for further investigation. Data presented here suggested that borreliosis “lato sensu” is in the Brazilian Amazon region.