Background: Lymphatic filariasis is a major public health problem in tropical countries. Earlier reports have reported microfilariae as an incidental finding in body fluids and fine needle aspiration smears from various sites.
Cases: The findings of body fluid cytology and fine needle aspiration smears from six patients with microfilariae in association with other conditions--tubercular pleural effusion/lymphadenitis, pregnancy and non-Hodgkin's lymphoma--are presented. Three patients demonstrated an associated eosinophilic cellular exudate. Adherence of inflammatory cells to microfilariae was seen in two patients.
Conclusion: Although microfilariae in cytologic smears are considered incidental findings, the association of microfilariae with debilitating conditions suggests that it is an opportunistic infection and needs further study.