Detection of intestinal protozoa by using different methods

A total of 305 stools samples during the period of October 2011 to June 2012 were collected from patients attending Brack General Hospital and Medical Technology, Department of Brack, Al-Shati, Libya. All stool samples were examined by direct smear preparation in normal saline, iodine, and eosin stains and 4 concentration methods (formalin-ether, normal saline sedimentation, zinc sulfate, and Sheather's sugar flotation). Of the 305 samples, 18.03% stools were found positive for protozoan parasites in direct smear microscopy. Normal saline sedimentation and zinc sulfate flotation detected 27.21% and 23.6% positive samples, respectively. However, formalin-ether was found to be the most sensitive method. Sheather's sugar flotation failed to detect Entamoeba histolytica/dispar , Entamoeba coli , and Blastocystis hominis . B. hominis was the most common parasite among the patients. Concentration techniques showed significantly higher ( P < 0.05) detection rates of parasites compared with direct smear microscopy.