Deep-Seated Lump in the Buccal Mucosa: Dirofilariasis

Abstract

Dirofilariasis is a zoonotic parasitic infection caused by a parasite nematode of the genus Dirofilaria, mostly living in animals especially in canines. Rarely the parasite can cause infections in human beings. It is a vector-borne disease and transmission to man occurs through the bite of potential mosquito vectors. There are more than 40 species that can cause human dirofilariasis, but the commonest is Dirofilaria repens. It commonly presents as a single non-tender subcutaneous nodule. Nodules can occur in any part of the body but commonly in head and neck area. Chronic inflammatory infiltration occurs around the living or dead parasite forming a parasitic granuloma. Mostly the patients are asymptomatic. Hematological investigations such as FBC are helpful in excluding bacterial infection. FBC shows elevated levels of eosinophils as seen in any parasitic infection. Radiological investigations such as ultrasonography, computed tomography and magnetic resonance imaging may be useful. Detection of anti-Dirofilaria repens antibodies is helpful in identifying the treatment response in cases treated with drugs. There are multiple treatment options available. The best treatment method is surgical removal. Medical treatment is also effective in some cases. Commonly used drugs include diethylcarbamazine (DEC), ivermectin and albendazole. Tetracycline and doxycycline have also been used with some success. The best way of minimizing the infection is by preventive measures. Proper control methods for mosquitoes and stray dogs are essential.