A case of a Caucasian girl with leukocytoclastic vasculitis, polyarthritis and eosinophilia is presented. A blood test showed microfilariasis, probably of the Loa Loa type. The epidemiology, clinical features, diagnosis and treatment of filariasis is described. In the western literature revised, reactive arthritis has been described but none of the other clinical features of our case. The presence of circulating immune complex might explain the pathogenic mechanism. We believe that filariae should be included amongst the causes of hypersensitivity vasculitis and in the differential diagnosis of eosinophilic vasculitis.