A case of orbital dirofilariasis in Northern Turkey.

A 29-year-old male patient presented with complaints of a localized mass behind his right lower eyelid that had been present for the last 6 months. Ophthalmologic examination was completely normal except for a 2 cm x 2 cm painless mass localized on the inferior orbital rim behind the right lower eyelid. An excisional biopsy was planned, and an anterior orbitotomy was performed by a lateral canthotomy and inferior cantholysis. Premature rupture of the cyst occurred during dissection, disclosing a thin white parasite surrounded by copious purulent material. The parasite and surrounding cyst were submitted to laboratory for evaluation. The parasite was typed as Dirofilaria repens (13 cm, female). The patient remained symptom-free over the 4 months of postoperative follow-up. Detection of the first human case of orbital dirofilariasis in Northern Turkey, in a patient with no history of travel to any endemic areas, has raised questions about the parasite's zoonotic characteristics.