Dientamoeba fragilis is a protozoan that inhabits the human colon and is responsible in degrees for clinical symptoms. These symptoms are: Local stomach pains, loss of weight and appetite and vomiting. Treatment with anti-parasite drugs will improve the symptoms. Due to misdiagnosis, prolonged undesired clinical signs can remain in patient. Diagnosis in stool specimens uses standard Iron-Haematoxylin staining and molecular polymerase chain reaction (PCR) and Nested-PCR methods that differ in sensitivity and specifity. The results presented here confirmed the sensitivity and specificity of 85 and 100% respectively. All negative results with staining method were also negative by PCR but six positive reported results were detected by staining and one positive sample was not detected by molecular method. This maybe the result of delay in processing samples for diagnosis which may mean the DNA is destroyed and made undetectable.

Key words: Dientamoeba fragilis, PCR, Chalous region, prevalence.