Fasciolosis
| Classification according to ICD-10 | |
|---|---|
| B66.3 | Fascioliasis |
| ICD-10 online (WHO version 2019) | |
The fascioliasis , the infestation with the large liver fluke ( Fasciola hepatica ) is a zoonosis , the ruminants , particularly sheep and cattle , infects. This originally European disease was introduced into the tropics by shipping cattle overseas. In Africa and Asia, Fasciola gigantica is the main causative agent of fasciolosis. Nowadays it only occurs sporadically in Central Europe. Human infections usually occur through the ingestion of metacercarial aquatic or riverine plants, such as watercress or lettuce . Water snails act as vectors , ingesting miracidia and excreting cercariae in the form of cysts . These encyst on the mentioned plants. The orally ingested metacercariae actively penetrate the intestinal mucosa and find their way to the liver tissue. When entering the liver capsule, a complication of a (subcapsular) hematoma under the liver capsule has been reported.
In exceptional cases, organs other than the liver ( ectopic lesions ) can be affected . Settlements in the skin ( dermal ), inside the eye ( intraocular ), in muscles, in the brain ( cerebral ), in the appendix , in the pancreas and in the epididymis ( ependydimal ) have been reported. More common are holdings of the pleura and pericardium , which is still unclear whether this to be infested with liver flukes or an immune-allergic reactions. The parasites finally penetrate the bile duct system and lead to remodeling processes in the bile duct epithelium , which ensure their survival over long periods of time.
It is estimated that 2.4 million people worldwide were infected in 1998 and 240 million were at risk of infection. In some regions, up to 60% of the population is infected.
parasitology
Paleoparasitological finds from Chalain , France suggest that infections with Fasciola hepatica occurred as early as the Neolithic . The analysis of 12 human coprolites and 10 sediment samples revealed some well-preserved eggs of Fasciola hepatica , Trichuris and Diphyllobothrium . Fasciola hepatica belongs to the class of trematodes ( flukes ). It is a hermaphrodite leaf-shaped leech 2–4 cm in length. Water snails of the genus Lymnaea act as intermediate hosts . The regular final hosts are herbivores (cattle, sheep), humans are occasional final hosts. The parasite can also complete its development cycle in humans.
distribution
Fasciolosis is a worldwide common zoonosis. Human infections usually occur sporadically or as a localized epidemic. Worldwide, the number of infected people is estimated at 2.4 to 17 million. School-age children are most frequently affected. In particular, countries with corresponding dietary habits such as the consumption of watercress or irrigation with metacercarial service water show a higher prevalence . Vegetarians have an increased risk of infection. Infection can occur from drinking water with free-floating metacercariae. There are increasing reports of infections in France, Cuba, Peru, the Middle East and the Nile Delta. A hyper-endemic region is the Bolivian highlands (" Altiplano "), where enough people are infected to maintain the life cycle.
Individual cases have been reported from natural herb collectors from Germany, as well as from returning tourists or immigrants.
Stages of infection
Three stages of the infection can be defined.
After ingestion of the metacercarials, they migrate from the intestinal area into the peritoneum within 2–24 hours and into the liver within 48 hours through the liver capsule ( Glisson's capsule ).
In the acute stage, the immature metacercariae transform into immature larvae, which migrate through the liver tissue and there produce cell necrosis and eosinophilic infiltrates. The acute stage lasts up to seven weeks. There is fever , weight loss, pain in the right upper abdomen and epigastrium , nausea and vomiting . There is an increase in eosinophil granulocytes in the blood ( eosinophilia ), increased liver enzymes and signs of cholestasis . Right basal eosinophilic pulmonary infiltrates can occur. 20-25% of patients have itching, urticaria , or both, often with dermatography .
The latent or "biliary" stage begins after about 2–4 months, when the juvenile leeches have migrated into the biliary tract and begin to produce eggs. The symptoms are not very pronounced, there are gastrointestinal complaints and eosinophilia . An unknown percentage of those infected remain without clinical symptoms. This phase can last months, years, or decades. The adult liver fluke cause inflammation and hyperplasia of the bile ducts up to biliary cirrhosis . In the course of a bacterial secondary infection, ascending cholangitis and cholecystitis can occur, as can acute pancreatitis . Mucosal erosion can lead to hemobilia , with bleeding from the bile duct system into the gastrointestinal tract. Mechanical biliary obstruction is possible in the case of massive worm infestation. Dead liver fluke may serve as a crystallization nucleus for concrete bile ducts .
In the chronic stage, but not before, yellowish-brown ovoid eggs can be detected in the stool, which are 130–150 µm long and 60–90 µm wide. On ultrasound it may be possible to see the parasites in the bile duct system, due to the spontaneous movements or as sickle-shaped bladder contents.
treatment
The agent of choice is triclabendazole , which, while being effective, is also highly tolerated. In Germany, however, no preparation based on triclabendazole is approved. Triclabendazole has been used in veterinary medicine since 1983, and after an outbreak in Iran in 1989, a human medicinal product was developed in Egypt and registered in 1997.
In asymptomatic human carriers, a case series showed a cure in 79% after a single dose of triclabendazole.
Triclabendazole is also used in animals. For food-producing animals, there is a waiting period of 50 days for edible tissues; milk must be discarded. In veterinary medicine, the following are also permitted in Germany: combinations of ivermectin and clorsulon , ivermectin and closantel and closantel and mebendazole .
The praziquantel , which is otherwise used as the agent of first choice for trematodes, is only slightly effective in fasciolosis.
Web links
Individual evidence
- ^ David Harrington, Poppy HL Lamberton, Alastair McGregor: Human liver flukes . In: The Lancet Gastroenterology & Hepatology . tape 2 , no. 9 , September 2017, p. 680-689 , doi : 10.1016 / S2468-1253 (17) 30111-5 (English).
- ↑ a b Robert W. Tolan: Fascioliasis Due to Fasciola hepatica and Fasciola gigantica Infection: An Update on This 'Neglected' Neglected Tropical Disease . In: Laboratory Medicine . tape 42 , no. 2 , February 2011, ISSN 0007-5027 , p. 107-116 , doi : 10.1309 / LMLFBB8PW4SA0YJI (English).
- ↑ a b c Dejan Micic, Aytekin Oto, Michael R. Charlton, Jean-Luc Benoit, Mark Siegler: Hiding in the Water . In: New England Journal of Medicine . tape 382 , no. 19 , May 7, 2020, p. 1844–1849 , doi : 10.1056 / NEJMcps1902741 (English).
- ↑ Red List , query on October 11, 2012.
- ↑ vetidata, query on October 11, 2012.
- ↑ S. Schubert, R. Phetsouvanh: praziquantel largely ineffective: treatment of Fasciola hepatica -Befalles (large liver fluke) . In: Journal for Medical Training . tape 84 , no. 14 . Jena 1990, p. 705-707 , PMID 2264356 .
- ^ TA Price, CU Tuazon, GL Simon: Fascioliasis. Case reports and review . In: Clinical Infectious Diseases . tape 17 , no. 3 , 1993, p. 426-430 , doi : 10.1093 / clinids / 17.3.426 , PMID 8218685 (English).
