Fasciolosis

The fascioliasis, the infestation of the Great liver fluke ( Fasciola hepatica), is a zoonosis that ruminants, especially sheep and cattle, infects. This originally European disease was introduced into the tropics through shipment of cattle to overseas. It occurs nowadays only sporadically in Central Europe. Human infections usually find by taking metazerkarienhaltiger water or shore plants, for example, watercress or lettuce instead. As vectors, water snails act, record the miracidia and cercariae secrete in cyst form. This encyst on the mentioned plants. The ingested metacercariae penetrate the intestinal mucosa and actively find their way to the liver tissue. While penetrating the liver capsule has been reported as a complication at a level below the liver capsule ( subcapsular ) hematoma.

In exceptional cases, it may lead to an infestation of organs other than the liver ( ectopic lesions). About metastases in the skin ( dermal), inside the eye ( intraocular ), in muscle, in the brain ( cerebral ), in the appendix, in the pancreas and in the epididymis ( ependydimal ) has been reported. More often, investments of the pleura and pericardium, where it is still unclear whether this is infestation with liver flukes or an immune- allergic reactions. The parasites eventually invade the bile duct system, where they cause remodeling of Gallengangsepithels that secure them to survive for long periods.

It is believed that in 1998 2.4 million people infected worldwide and 240 million were at risk of infection. In certain regions up to 60% of the population is infected.

Parasitology

Palaeoparasitologische finds from chalain France suggest that infection with Fasciola hepatica have already taken place in the Neolithic period. The analysis of 12 human coprolites and 10 sediment samples brought to light some well-preserved eggs of Fasciola hepatica, Trichuris and Diphyllobothrium. Fasciola hepatica belongs to the class of trematodes ( flukes ). He is a hermaphrodite leaf -shaped flukes of 2-4 cm length. As an intermediate host snails of the genus Lymnaea water act. The regular final hosts are herbivores (cattle, sheep), the man is an occasional definitive host. The parasite can complete its life cycle in humans.

Dissemination

The fascioliasis is a zoonosis distributed worldwide. Human infections are usually sporadic or localized epidemic. In particular, countries with appropriate eating habits such as eating watercress or irrigation with metazerkarienhaltigem domestic water show a higher prevalence. In France, Cuba, Peru, the Middle East and in the Nile Delta is reported increased infection. Single cases have been reported from Germany with natural herb collectors.

Stages of infection

There can be distinguished three stages of infection.

The acute stage occurs after about 2-6 weeks at Metazerkarienbefall massive in appearance. There will be fever, pain in the right upper abdomen and epigastrium, nausea and vomiting. There will be an increase in eosinophils in the blood ( eosinophilia), elevated liver enzymes and Cholestasezeichen. It can right - basal eosinophilic pulmonary infiltrates occur.

The latent stage begins when the juvenile flukes have migrated into the bile duct system and begin egg production. The symptoms are very pronounced, it can be found gastrointestinal symptoms and an increased eosinophil count. An unknown percentage of those infected will have no clinical symptoms. This phase can last months or years, and passes into the chronic stage. The adult liver fluke provide for inflammation and hyperplasia of the bile duct to biliary cirrhosis. In the course of a secondary bacterial infection may lead to cholangitis and cholecystitis. If a large worm infestation mechanical biliary obstruction is possible. Dead liver flukes may serve as nucleation for Gallengangskonkremente.

Treatment

Medium of choice is triclabendazole that a good efficiency also has a high tolerance. In Germany, however, no preparation is approved on the basis of triclabendazole.

In animals, triclabendazole is also used. For edible tissues consists in food-producing animals, a waiting period of 50 days, milk should be discarded. In veterinary medicine, are also permitted in Germany: combination preparations of ivermectin and clorsulon from ivermectin and Closantel and from Closantel and mebendazole.

Praziquantel shows little effectiveness.