Onchocercosis mansonella co-infection presenting as a subcutaneous nodule in a child.

A 11-year-old girl presented with a subcutaneous lesion on the forehead, thought to be an implantation dermoid cyst. Microscopic examination revealed an onchocercoma. Microfilariae were found in the blood indicating a co-infection with Mansonella perstans. This case demonstrates the diagnostic difficulties of a parasitic co-infection uncommonly encountered in Europe.