Cestoda Flashcards
Hoe lang wordt Hymenolepis nana?
1.5 - 4 cm
Hoe lang wordt Taenia saginata/ solium?
2 - 8 meter (large tapeworm)
Hoe lang wordt Diphyllobothrium latum?
4-10 meter (broad tapeworm)
Is echinococcosis een zoonotische infectie?
Ja
Welke cestoda veroorzaken human echinococcosis?
E. granulosus (hydatid disease)
E. multilocularis (alveolar echinococcosis)
E. vogelii
E. oligarthrus
Welke twee Echinococcus species veroorzaken human echinococcosis?
E. granulosus en E. multilocularis
Wat voor cysten veroorzaken E. granulosus?
Unilocular cysts in de lever en de longen
Wat voor cysten veroorzaken E. multilocularis?
Tumour-like cysten in de lever
Wat is de levenscyclus van E. granulosus?
The adult Echinococcus granulosus (sensu lato) (2—7 mm long) image resides in the small intestine of the definitive host. Gravid proglottids release eggs image that are passed in the feces, and are immediately infectious. After ingestion by a suitable intermediate host, eggs hatch in the small intestine and release six-hooked oncospheres image that penetrate the intestinal wall and migrate through the circulatory system into various organs, especially the liver and lungs. In these organs, the oncosphere develops into a thick-walled hydatid cyst image that enlarges gradually, producing protoscolices and daughter cysts that fill the cyst interior. The definitive host becomes infected by ingesting the cyst-containing organs of the infected intermediate host. After ingestion, the protoscolices image evaginate, attach to the intestinal mucosa image , and develop into adult stages image in 32 to 80 days.
Humans are aberrant intermediate hosts, and become infected by ingesting eggs image . Oncospheres are released in the intestine image , and hydatid cysts develop in a variety of organs image . If cysts rupture, the liberated protoscolices may create secondary cysts in other sites within the body (secondary echinococcosis).
Wat is de levenscyclus van E. multilocularis?
The adult Echinococcus multilocularis (1.2—4.5 mm long) image resides in the small intestine of the definitive host. Gravid proglottids release eggs image that are passed in the feces, and are immediately infectious. After ingestion by a suitable intermediate host, eggs hatch in the small intestine and releases a six-hooked oncosphere image that penetrates the intestinal wall and migrates through the circulatory system into various organs (primarily the liver for E. multilocularis). The oncosphere develops into a multi-chambered (“multilocular”), thin-walled (alveolar) hydatid cyst image that proliferates by successive outward budding. Numerous protoscolices develop within these cysts. The definitive host becomes infected by ingesting the cyst-containing organs of the infected intermediate host. After ingestion, the protoscolices image evaginate, attach to the intestinal mucosa image , and develop into adult stages image in 32 to 80 days.
Humans are aberrant intermediate hosts, and become infected by ingesting eggs image . Oncospheres image are released in the intestine and cysts develop within in the liver image . Metastasis or dissemination to other organs (e.g., lungs, brain, heart, bone) may occur if protoscolices are released from cysts, sometimes called “secondary echinococcosis.”
Wat zijn de definitieve en intermediaire gastheren van E. granulosus?
Echinococcus granulosus definitive hosts are wild and domestic canids. Natural intermediate hosts depend on genotype. Intermediate hosts for zoonotic species/genotypes are usually ungulates, including sheep and goats (E. granulosus sensu stricto), cattle (“E. ortleppi”/G5), camels (“E. canadensis”/G6), and cervids (“E. canadensis”/G8, G10).
Wat zijn de definitieve en intermediaire gastheren van E. multilocularis?
For E. multilocularis, foxes, particularly red foxes (Vulpes vulpes), are the primary definitive host species. Other canids including domestic dogs, wolves, and raccoon dogs (Nyctereutes procyonoides) are also competent definitive hosts. Many rodents can serve as intermediate hosts, but members of the subfamily Arvicolinae (voles, lemmings, and related rodents) are the most typical.
Wat zijn de definitieve en intermediaire gastheren van E. vogeli en E. oligarthus?
The natural definitive host of E. vogeli is the bush dog (Speothos venaticus), and possibly domestic dogs. Pacas (Cuniculus paca) and agoutis (Dasyprocta spp.) are known intermediate hosts. E. oligarthrus uses wild neotropical felids (e.g. ocelots, puma, jaguarundi) as definitive hosts, and a broader variety of rodents and lagomorphs as intermediate hosts.
Hoe ziet een hydatide cyst eruit?
Cyst inhoud: protoscolices, hooks, hydatid sand, laminated layer
Wat is de levenscyclus van Taenia?
Taeniasis is the infection of humans with the adult tapeworm of Taenia saginata, T. solium or T. asiatica. Humans are the only definitive hosts for these three species. Eggs or gravid proglottids are passed with feces The number 1; the eggs can survive for days to months in the environment. Cattle (T. saginata) and pigs (T. solium and T. asiatica) become infected by ingesting vegetation contaminated with eggs or gravid proglottids The number 2. In the animal’s intestine, the oncospheres hatch The number 3, invade the intestinal wall, and migrate to the striated muscles, where they develop into cysticerci. A cysticercus can survive for several years in the animal.
Humans become infected by ingesting raw or undercooked infected meat The number 4. In the human intestine, the cysticercus develops over 2 months into an adult tapeworm, which can survive for years. The adult tapeworms attach to the small intestine by their scolex The number 5 and reside in the small intestine The number 6. Length of adult worms is usually 5 m or less for T. saginata (however it may reach up to 25 m) and 2 to 7 m for T. solium. The adults produce proglottids which mature, become gravid, detach from the tapeworm, and migrate to the anus or are passed in the stool (approximately 6 per day). T. saginata adults usually have 1,000 to 2,000 proglottids, while T. solium adults have an average of 1,000 proglottids. The eggs contained in the gravid proglottids are released after the proglottids are passed with the feces. T. saginata may produce up to 100,000 and T. solium may produce 50,000 eggs per proglottid respectively.
Wat zijn de symptomen van E. granulosus?
Echinococcus granulosus infections often remain asymptomatic for years before the cysts grow large enough to cause symptoms in the affected organs. The rate at which symptoms appear typically depends on the location of the cyst. Hepatic and pulmonary signs/symptoms are the most common clinical manifestations, as these are the most common sites for cysts to develop In addition to the liver and lungs, other organs (spleen, kidneys, heart, bone, and central nervous system, including the brain and eyes) can also be involved, with resulting symptoms. Rupture of the cysts can produce a host reaction manifesting as fever, urticaria, eosinophilia, and potentially anaphylactic shock; rupture of the cyst may also lead to cyst dissemination.
Wat zijn de symptomen van E. multilocularis?
Echinococcus multilocularis affects the liver as a slow growing, destructive tumor, often with abdominal pain and biliary obstruction being the only manifestations evident in early infection. This may be misdiagnosed as liver cancer. Rarely, metastatic lesions into the lungs, spleen, and brain occur. Untreated infections have a high fatality rate.
Wat zijn de symptomen van E. vogeli?
Echinococcus vogeli affects mainly the liver, where it acts as a slow growing tumor; secondary cystic development is common. Too few cases of E. oligarthrus have been reported for characterization of its clinical presentation.
Wat is de “beef tapeworm”?
Taenia saginata
Wat is de “pork tapeworm”?
Taenia solium
Wat is de “asian tapeworm”?
Taenia asiatica
Welke Taenia veroorzaakt cysticercosis?
T. solium
