Microfilaria in Thyroid Fine –Needle Aspiration cytology : A Rare Case Report

Filariasis is a global health problem particularly  in tropical countries like India. About 90% of cases of lymphatic filariasis are caused by infection with Wuchereria bancrofti and rest by Brugia malayi in Southeast Asia. Filariasis is transmitted by the bite of Culex mosquitoes. The diagnosis of it is conventionally made by demonstrating microfilaria in the peripheral blood smear. Increasingly, these larvae are discovered incidentally during fine-needle aspiration cytology (FNAC) at various anatomical sites; however, their documentation within thyroid nodules remains exceedingly rare. This report details an unusual clinical presentation where routine thyroid nodule aspiration unexpectedly revealed the presence of microfilariae.