Comparison of the FeKal CON-Trate system with the formalin-ethyl acetate technique for detection of intestinal parasites.

The ability of the FeKal CON-Trate system (Trend Scientific, Minneapolis, Minn.) to recover parasite ova, cysts, or larvae from 300 fecal specimens was compared with that of the Formalin-ethyl acetate sedimentation technique. One hundred stool samples had previously been determined to contain 129 parasite forms. The FeKal system detected 127 parasites (sensitivity, 98.4%), and the Formalin-ethyl acetate sedimentation technique detected 125 parasites (sensitivity, 96.9%). Higher counts of parasite forms were obtained for 11 of 14 species of parasites in specimens prepared by the FeKal system. Four specimens were negative by the Formalin-ethyl acetate method and two by the FeKal system. These false-negative observations occurred in specimens with low counts of parasites. There were no false-positive results.