[Erythema chronicum migrans (Lyme's disease). Clinico-epidemiologic study of 10 cases].

Migratory Chronic Erythema (MCE), which is the distinctive and diagnostic lesion of Lyme's disease, could manifest itself under different clinical manifestations. Following a clinical and a epidemiological point of view 10 cases of MCE, diagnosed during the last three years, have been studied and described. Its wide variability of the clinical manifestations is underlined, with a mean incubation period of 5.6 days between the onset of cutaneous symptoms and the tick bite. The zones mainly affected were lower limbs followed by trunk and neck. Size of lesion varied from 5 to 30 cm, with a mean of 13 cm. In two patients satellite cutaneous lesions were observed and six showed extra-cutaneous signs. Only in four patients antibodies against Borrelia burgdorferi were detected. Regarding epidemiology we did not found differences between the sexes, or by living on an urban or rural area. The tick bite was referred in half of the cases, 30% of the patients have a job related with wood, forest, farming or cattle. The season in which MCE was most frequent was spring-beginning of summer and end of summer-beginning of autumn. All patients responded to the therapy with tetracyclines and/or macrolides.