Borrelia and rickettsia in skin bioptates of erythema migrans patients

Sa？etak Lyme borreliosis is a multisystem inflammatory disease caused by spirochete Borrelia burgdorferi sensu lato complex which are usually transmitted by Ixodes ricinus ticks. In Croatia, little is known about the borrelia species prevalence. As the same vector is responsible for transmiting rickettsia, one should assume the possibility of borrelia and rickettsia coinfections. The purpose of this study was to identify borrelia species present in our environment and to establish if coinfections with rickettsias are present. Skin biopsy of erythema migrans active edge was performed, and samples were analyzed by molecular methods. Borrelia were found in 38/56 samples, out of which 36 B. afzelii were detected. In two samples rickettsia were found: R. monacensis and R. bellii. This paper is the first description of R. bellii detected in human tissue in the world and the first description of R. monacensis in Croatia. Unusual homogeneous B. afzelii prevalence as well as detected rickettsia point out the need for further investigations