Incidental detection of microfilariae on fine needle aspiration cytology smear

Abstract

<h3>Introduction</h3> Lymphatic filariasis is a disabling parasitic disease that is a global health problem endemic in Nigeria. Peripheral blood smears are frequently negative for microfilaria. In such individuals conventional diagnostic methods may fail to identify the disease. The demonstration of microfilaria in fine needle aspiration cytology smears is not a very common finding. <h3>Patient and method</h3> We report the incidental finding of micro-filaria in a fine needle aspirate from a patient presenting with a groin swelling suspected to be a lymphoma. The clinical notes of the patient were reviewed and all relevant information extracted. The surgical pathology findings on gross and microscopic examination were also reviewed. <h3>Results</h3> A 49-year-old male farmer, domiciled in one of the south-western states of Nigeria, presented with a one year history of a right groin swelling which suddenly became painful about 2 weeks before coming to the hospital. A clinical assessment of lymphogranuloma venereum was made to rule out a non-Hodgkin lymphoma. Initial laboratory investigations only showed mild eosinophilia and haematuria. However, a fine needle aspiration cytology performed on the swelling showed microfilaria of <i>W. bancrofti</i> for which appropriate treatment was commenced with excellent outcome. <h3>Conclusion</h3> Although the vast majority of microfilariae are incidentally detected in cytological smears, aspiration cytology still plays a significant role in the diagnosis of filariasis, especially in resource poor countries.