Fascioliasis

From Wikipedia, the free encyclopedia

You have new messages (last change).

Fascioliasis is caused by the trematodes Fasciola hepatica (the sheep liver fluke) and Fasciola gigantica, parasites of herbivores that can infect humans accidentally. In agriculture, Fasciola infections cause losses totalling billions of dollars due to poor meat quality and loss of milk production and condemnation of livers.

Contents

[edit] Geographic Distribution

Fascioliasis occurs worldwide. Human infections with F. hepatica are found in areas where sheep and cattle are raised, and where humans consume raw aquatic plants like watercress, including Europe, the Middle East, and Asia. Infections with F. gigantica have been reported, more rarely, in Asia, Africa, and Hawaii. Specific species of snails as intermediate hosts have to be present also (Pulmonata, Genera Lymnaea, Fossaria, Galba, Radix ).

[edit] Clinical Features

During the acute phase (caused by the migration of the immature fluke through the hepatic parenchyma), symptoms include abdominal pain, hepatomegaly (enlarged liver), fever, vomiting, diarrhea, urticaria and eosinophilia, and can last for months. In the chronic phase (caused by the adult fluke within the bile ducts), the symptoms are more distinct and reflect intermittent biliary obstruction and inflammation. Occasionally, ectopic locations of infection (such as intestinal wall, lungs, subcutaneous tissue, and pharyngeal mucosa) can occur.

[edit] Laboratory Diagnosis

Microscopic identification of eggs is useful in the chronic (adult) stage for diagnosis. Eggs can be recovered in the stools or in material obtained by duodenal (small intestine) or biliary drainage. They are morphologically indistinguishable from those of the fluke F. buski. False fascioliasis (pseudofascioliasis) refers to the presence of eggs in the stool resulting not from an actual infection but from recent ingestion of infected livers containing eggs. This situation (with its potential for misdiagnosis) can be avoided by having the patient follow a liver-free diet several days before a repeat stool examination. Antibody detection tests are useful especially in the early invasive stages, when the eggs are not yet apparent in the stools, or in ectopic fascioliasis.

Bold text==Treatment== Unlike infections with other flukes, F. hepatica infections may not respond to Praziquantel. The drug of choice is triclabendazole with bithionol as an alternative. Nitazoxanide is also a very potent drug of choice for such infections.

[edit] High prevalence in the Bolivian Altiplano

In the high plane of Bolivia, about 15% of the population is infected with Fasciola hepatica:

  • "Case-control analysis indicated that the only factor associated with illness was eating kjosco (an aquatic plant) while tending animals in the fields; 27 (52%) of the 52 case-patients vs. 9 (14%) of the 66 controls ate kjosco (OR = 6.84; 95% CI = 2.60, 18.44)...... Fascioliasis is a significant human health problem and is highly endemic in the Aymara Indian community in the Bolivian Altiplano. Efforts to prevent fascioliasis should include educating people to avoid eating uncooked aquatic plants such as kjosco." cited from: An outbreak of acute fascioliasis among Aymara Indians in the Bolivian Altiplano. (1996) [1].
  • "Humans are infected by drinking contaminated fresh or field water, or by consuming uncooked aquatic plants, especially watercress (berro), algae (algas), tortora (corr.:Totora), and kjosco." cited from: Hypereosinophilia and liver mass in an immigrant, 2002, [2].

[edit] External links

Retrieved from "http://en.wikipedia.org../../../f/a/s/Fascioliasis.html"
In other languages