الفهرس 
Taxonomic ClassificationOnly 14 pages are availabe for public view
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Abstract
Fascioliasis can no longer be considered merely a secondary zoonotic disease, but is now an important human parasitic disease.The infection occurs by ingestion of aquatic plants that contain infective metacercariae resultimg in biliary cirrhosis, sclerosing cholangitis associated with destructive jaundice, liver abscesses, and other serious hepatic and ectopic clinical manifestations.
Early diagnosis of fascioliasis is necessary for prompt treatment before irreparable damage to the liver occurs. The parasitological diagnosis of human fascioliasis is often unreliable because the parasite eggs are not found in the stool during the early phase of infection. Even when the worms have matured, the diagnosis may still be difficult since eggs are only intermittently released.
Therefore, immunonological methods such as ELISA and Western blot are the most important methods in diagnosis of Fasciola infection. A diversity of Fasciola antigens either somatic or from E-S products were studied. E-S antigens have more contact with host immune system, thus, inducing a specific and stronger humoral immune response than somatic antigens.
The present study aimed at evaluating the diagnostic efficacy of Fasciola adult worm vomit preparation in diagnosis of human fascioliasis using conventional-ELISA and FAST-ELISA in comparison with Fasciola adult total soluble extract.
This study was conducted on three groups of patients who attended the Diagnostic and Research Unit in the Parasitology Department, Faculty of Medicine -Ain Shams University at time interval from July 2011 to May 2012).
Group I: (group of fascioliasis patients) consists of 20 cases of fascioliasis were diagnosed by positive stool examination and positive IHAT for fascioliasis and negative for other parasitic infections by negative IHAT specific for each disease. Group II: (group of patients with other parasitic infections) consists of 20 cases that were negative for fascioliasis and positive for other parasitic infections by positive IHAT specific for each disease (5 cases of hydatidosis, 5 cases of intestinal schistosomiasis, 5 cases of toxoplasmosis and 5 cases of amoebiasis).Group III: (normal control group) consists of 10 apparently healthy individuals, confirmed to be free from fascioliasis and other parasitic infections by negative stool examination and negative IHAT kit specific for each disease.
Two types of antigens, the total soluble extract and adult worm vomit, were prepared from adult Fasciola gigantica worms which were collected from the bile ducts of naturally infected liver of cattle from a local abattoir at Cairo, Egypt. As identified by it’s morphological characters.
After that, the two antigens were evaluated using conventional ELISA and Falcon Assay Screening Test (FAST-ELISA) after doing standardization methods in order to reach optimum conditions for each types of ELISA.
The results of the conventional ELISA were as the following, using TSE antigen, sensitivity was 95%, specificity was 93.3% with cross reactions with one case of hydatidosis and one case of amoebiasis. The PPV and NPV were 90.4 and 96.5%, respectively and the diagnostic accuracy of the test was 94%. Whereas, the diagnostic accuracy of conventional ELISA using AWV was 98% with 100% sensitivity, 96.7% specificity as one case of schistosomiasis was positive. The PPV and NPV were 95.2% and 100%, respectively.
Regarding FAST-ELISA using TSE antigen, the sensitivity was 95%, specificity was 96.7% specificity with cross reaction with one case of hydatidosis. The PPV and NPV were 95% and 96.7%, respectively and the diagnostic accuracy was 96%. While, FAST-ELISA using AWV antigen showed that the diagnostic accuracy was 100% with 100% sensitivity and 100% specificity, PPV and NPV were 100% for each.
In conclusion, results of the present study highlighted the efficacy of F. gigantica AWV preparation in diagnosis of human fascioliasis, it seems to be a promising antigen improving the sensitivity, specificity and diagnostic accuracy of conventional and FAST-ELISA.