Diagnostic performance of direct wet mount microscopy in detecting intestinal helminths among pregnant women attending ante-natal care (ANC) in East Wollega, Oromia, Ethiopia

Abstract

Objective: The aim of this study was to evaluate the diagnostic performance of direct wet mount microscopy compared to formalin ether concentration (FEC) technique in detecting intestinal helminths in pregnant women. Results: The total prevalence of intestinal helminths was 18.8% (70/372) by direct wet mount microscopy and 24.7% (92/372) by FEC technique (P < 0.001). The sensitivity, negative predictive value (NPV) and test efficiency (TE) of direct wet mount microscopy in diagnosing intestinal helminths was 76, 92.7 and 94%, respectively. The sensitivity of direct w et mount microscopy was very low in detecting ova of Hymenolepis nana. The two methods showed excellent agreement in detecting ova of Hook worm and Ascaris lumbricoides (Kappa > 0.81) but they fairly agreed in detecting ova of Hymenolepis nana (Kappa = 0.39). Intestinal helminths were underdiagnosed and the total diagnostic performance of direct wet mount microscopy was significantly poor in detecting intestinal helminths as compared to FEC technique. Routine use of FEC method is recommended for the diagnosis of intestinal helminths in pregnant women.