Human subcutaneous dirofilariasis: a report of three cases manifesting as breast or axillary nodules.

Human subcutaneous dirofilariasis is a rare infection caused by filarial worms of the genus Dirofilaria. The parasites are transmitted to man by zooanthropophilic bloodsucking insects and the infection is manifested as subcutaneous nodules. Excisional biopsy is both diagnostic and therapeutic. We herein report three cases of human subcutaneous dirofilariasis diagnosed, over a period of ten years (1991-2000), in North East Greece. The patients, two women and one man, were all adults between 32 and 67 years of age. In two cases the infection was manifested as breast nodules, while in the third case as a painful nodule in the axillary region. The excisional biopsy showed the presence of an adult Dirofilaria, identified as Dirofilaria (Nochtiella) repens. It is emphasised that both clinicians and pathologists should have an increased awareness of this clinicopathologic entity and include dirofilariasis in the differential diagnosis in patients presenting with breast or subcutaneous nodules.