A new modified technique for concentrating intestinal parasites

The present study evaluated the diagnostic performance of a modification of the formol ethyl acetate concentration technique, with the addition of 25% acetic acid as compared with formol ethyl acetate concentration technique (FEA) and fecal parasite concentrator kit Fresh fecal material, free of ova and parasites, was pooled in a ratio of 1:4 with 10% buffered formalin to prepare a standardized specimen. Sufficient volumes of formalin-fixed suspension of Giardia lamblia cysts, Entamoeba histolytica cysts, Cryptosporidium oocysts; Ascaris lumbricoides ova, Necator americanus, Taenia spp. and Hymenolepis nana were used to seed individually 3-ml portions of the fecal specimen. The 3-ml samples were split in three parts, one processed by FEA, a second part with FPC and the third part by the modified FAEA; six smears from each sediment were examined by light microscopy. FAEA technique gave the clearest sediments and the highest numbers in most of the parasites. FAEA resulted in a higher percenttage of H. nana, Taenia spp., N. americanus, and G. lamblia per one ml of stool compared with FEA method. When compared with FPC, the same results were achieved in addition to E. histolytica.