Fiftyone patients with a diagnosis of erythema chronicum migrans (ECM), lymphadenosis cutis benigna (LABC), systemic progressive sclerosis, localized scleroderma and lichen sclerosus et atrophicans were investigated in order to obtain serological evaluation of Borrelia burgdorferi circulating antibodies. In addition sera from 9 patients with pellagroid erythema, prurigo and panniculitis were performed: in these dermatoses there was no evidence of a possible borrelia relationship. Indirect immunofluorescence assay was used for serologic testing. Elevated IgG antibody titers were detected in one female patient with localized scleroderma (1:128) and in one male patient with LABC (1:64). Serologic testing was not positive in the other 58 patients. The very small number of patients with positive antibodies in our study would indicate that Borrelia burgdorferi infection is sporadic in Lazio.