ACCURACY OF DIAGNOSIS OF INTESTINAL HELMINTH PARASITES IN A REFERENCE DIAGNOSTIC LABORATORY IN THE ASHANTI REGION OF GHANA

Abstract

There are reports of many intestinal-helminth negative stool specimens in most laboratories in Ghana even though the prevalence of these infections seems to be on the increase. In this study 2000 stool specimens collected between May and October 2008 in The Reference Laboratory of the Ashanti Region of Ghana were screened using Direct Wet Mount, Kato-Katz and Formol-Ether Concentration methods. The Formol-Ether Concentration method gave the highest prevalence (11.1%) of helminth parasites made up of hookworm, Dicrocoelium dendriticum, Strongyloides stercoralis, Schistosoma mansoni, Hymenolepis nana, Taenia species and Trichuris trichiura. The direct wet mount and Kato-Katz detected total prevalence of 3.2% and 5.1% respectively. Kato-Katz showed good agreement with the formol-ether concentration in the detection of hookworms, T. trichiura and S. mansoni infections (99.1% sensitivity) with positive and negative predictive values of 100% and 99.5% respectively. This study confirmed earlier reports that the traditional Direct Wet Mount screening test is less sensitivity hence the employment of Formol-Ether Concentration as a confirmatory test in routine laboratory examination of stool samples will significantly reduce misdiagnosis of intestinal helminth infections and its attendant public health consequences.