HUMAN DIROFILARIASIS

Background. Subcutaneous and pulmonary dirofilariasis in humans appear s to be a frequent disease in endemic areas, notably the Mediterranean region. Following increased air travel in recent years, the incidence of human dirofilariasis has increased in tourists as well. Methods. T he clinical and parasitologic aspects in a series of six patients with cutaneous and pulmonary dirofilariasis, seen in a German unit for inf ectious and tropical diseases, are reviewed. Results. Four patients pr esented with subcutaneous tumors due to infection with Dirofilaria rep ens, whereas two patients had pulmonary infiltrates due to the canine heartworm, D. immitis. All infections were acquired in the Mediterrane an region. Symptoms were only slight and nonspecific. Eosinophilia in the blood was absent in all patients. The serum IgE levels were normal and signs of a specific humoral response to antigens of Dirofilaria s pp. were absent, although slightly elevated antibody levels to antigen s of Onchocerca volvulus could be demonstrated in all patients. The di agnosis was established in all patients by the surgical removal of adu lt worms from the lesions. Oral treatment with diethylcarbamazine (DEC ) (2 mg per kg t.i.d.) over a period of 4 weeks was added to the surgi cal treatment in all patients. In one patient this therapy was precede d by oral ivermectine (150 mg per kg). Conclusions. Dirofilariasis has to be considered as a differential diagnosis in patients presenting w ith subcutaneous or pulmonary tumors after travels to endemic areas wi thin the last few years. Effective therapy is possible by surgical rem oval of the adult worms and oral ivermectine plus diethylcarbamazine.