Enzyme Immunoassay for the Determination of Fasciola hepatica IgG Level in Human Serum
Introduction
Fasciola hepatica, a trematode parasite, affects livestock such as cattle and sheep, with human infection becoming more prevalent since 1980 (WHO, 1980). Fascioliasis complications primarily result from the parasite’s migration to the liver and biliary tract, leading to hepatocyte damage. Infected individuals may experience liver spasms, nausea, abdominal pain, diarrhea, anemia, and eosinophilia. The confirmatory test for fascioliasis typically involves the identification of parasite eggs in feces or duodenal lavage, although this method has limitations, including delayed detection and potential false positives from consuming infected animal liver (Garcia, 2001).
Clinical Significance
Fasciola hepatica is a trematode parasite that primarily affects livestock such as cattle and sheep. Human infections have been increasingly reported since 1980 (World Health Organization, WHO, 1980). The parasite is prevalent in many regions worldwide, with epidemics reported in several countries. The disease, known as fascioliasis, often involves migration of the parasite to the liver and biliary tract, causing significant damage to liver hepatocytes. Adult worms present in bile ducts can result in mechanical and toxic damage, which, in advanced stages, leads to cirrhosis and secondary bacterial infections.
The clinical manifestations of fascioliasis include liver spasms or cramps (RUQ pain), nausea, vomiting, abdominal pain, headache, irregular fever with sweating, diarrhea, anemia, and eosinophilia in peripheral blood. While the confirmatory diagnostic method is based on identifying parasite eggs in feces or duodenal lavage, these methods suffer from limitations. Egg detection is typically only possible 7–11 weeks after infection, and false positives can occur when patients ingest contaminated animal liver (pseudo-fasciolosis).
An effective alternative diagnostic method is the Fasciola hepatica IgG ELISA test, which allows detection of antibodies as early as 2–4 weeks post-infection with high sensitivity (~98%). However, cross-reactions with Schistosoma species have been reported.
Test Principle
The Fasciola hepatica IgG ELISA Kit is an enzyme immunoassay designed for the determination of Fasciola hepatica IgG levels in human serum or plasma samples. The assay is based on an indirect ELISA to detect specific antibodies against Fasciola hepatica. The test utilizes antigen-coated wells, where patient samples are added and allowed to bind to the antigens. A horseradish peroxidase (HRP)-labeled anti-human IgG antibody is then used to detect the presence of bound antibodies. The final reaction generates a color change that can be measured spectrophotometrically at 450 nm.
References
- Garcia, L. S. (2001). Diagnostic medical parasitology (4th ed.). American Society for Microbiology.
- Liu, L. X., & Harinasuta, K. T. (1996). Liver and intestinal flukes. Gastroenterol Clin North Am, 25(3), 627–636.
- Mascomas, S., Bargues, M. D., & Valero, M. A. (2005). Fascioliasis and other plant-borne trematode zoonoses. International Journal for Parasitology, 35(11), 1255–1278.
- World Health Organization (WHO). (1980). Fascioliasis. WHO Report.