Hymenolepis nana has been called the dwarf tapeworm and has a worldwide distribution. Hymenolepiasis is the most common intestinal tapeworm infection of humans caused by worm of family cestoda, genus hymenolepis and species nana. He recovered a countless number of them at a postmortem on a boy who had died of meningitis. Hymenolepis nana merupakan parasit yang termasuk dalam kelas cestoda yang hidup dalam usus manusia dan dapat menyebabkan penyakit hymenolepiasis nana atau dwarf tape worm infection. Cacing ini tidak memiliki hospes intermedier sehingga disebut dengan non obligatory intermedier, sedangkan hospes definitifnya adalah manusia. In 1906, stiles identified an identical parasite with a rodent host and named it hymenolepis fraterna. Humans and other animals become infected when they intentionally or unintentionally eat material contaminated by insects.
The disease is a type of helminthiasis which is classified as a neglected tropical disease. Hymenolepis nana definition of hymenolepis nana by medical. Hymenolepis nana, the dwarf or dwarf mouse tapeworm, is a small tapeworm in humans, sometimes found in great numbers in the intestine. Hymenolepis nana is also known as the dwarf tapeworm. Hymenolepis nana life cycle online biology dictionary. Hymenolepis nana dwarf tapeworm parasites in humans. Hymenolepiasis is the term when a human is infected with either h. If larvabearing eggs enter the human gastrointestinal tract, the oncospheres are released into the duodenum and attatch to the villi, where each develops into a cysticercoid. Himenolepiasis parasitologia humana accessmedicina. She remained well in spite of treatment, even though. It has slightly bigger eggs and proglottids than h. Dwarf tapeworm hymenolepis nana, also known as rodentolepis nana, vampirolepis nana, hymenolepis fraterna, and taenia nana is a cosmopolitan species though most common in temperate zones, and is one of the most common cestodes a type of intestinal worm or helminth infecting humans, especially children. See more ideas about medical laboratory, microbiology and medical laboratory science. Here, we present a case of a renal transplant recipient who presented with abdominal pain and developed diarrhea.
Nov 22, 2015 hymenolepiasis is the term when a human is infected with either h. It requires only one host but can also cycle through two. Himenolepiasis parasitologia medica, 4e accessmedicina. This cestode belongs to a large family known as hymenolepididae. It is possible for the worms entire life cycle to be completed in the bowel, so infection can. This infection does not require an intermediate host and infection can occur directly from one infected person to another by fecaloral transmission. The authors cite some ear lier cases as examples of proliferating. Its larvae migrate only within the gut wall, and its life span is relatively short 4 to 6 wk. Hymenolepiasis is an infection caused by hymenolepis nana h.
It is small and measures up to 2540 mm in length by one mm in diameter. On the inner membrane are two poles, from which 4 to 8 polar filaments spread out between the two membranes. Hymenolepis diminuta is a tapeworm that can cause intestinal infection in humans. Hymenolepis nana, a tiny intestinal tapeworm, is the most common human cestode. Eggs hatch in the duodenum, releasing oncospheres, which penetrate the mucosa and come to lie in lymph channels of the villi. When eggs are ingested by an arthropod intermediate host various species of beetles and fleas may serve as intermediate hosts, they develop into cysticercoids, which can infect humans or rodents upon. Creepy dreadful wonderful parasites blog case of the week 539 accessed 18 april 2019. Praziquantel, adults and children, 25mgkg in a singledose therapy alternatives. Humans and other animals become infected when they intentionally or. Malignant transformation of hymenolepis nana in a human. Human infection is usually asymptomatic, it but can cause mild gastrointestinal symptoms.
E ggs of the tapeworm hymenolepis nana are infective when passed with the stool, but cannot survive more than about 10 days outside the body when eggs are ingested by an arthropod intermediate host a variety of fleas and beetles can serve as intermediate hosts, they develop into cysticercoids, which can infect humans or rodents upon ingestion and develop into adults in the small intestine. Hymenolepis nana has a worldwide distribution with estimates of 5075 million carriers. Hymenolepis diminuta infection infectious diseases msd. Cdc hymenolepis resources for health professionals.
Infection is most common in children, in persons living in institutional settings, and in people who live in areas where sanitation and personal hygiene is inadequate. For precise diagnosis of the species, molecular techniques such as pcr and rflp of. Hymenolepis rodentolepis nana is the most common cestode of humans, particularly in young children. Hymenolepis nana introduction hymenolepis nana, the dwarf tapeworm, is the smallest tapeworm to infect humans. Hymenolepis diminuta, also known as rat tapeworm, is a species of hymenolepis tapeworm that causes hymenolepiasis. Biologia simplificada com emerson inacio 6,583 views. Hymenolepis nana is the smallest of all tapeworms found in humans and is appropriately described as the dwarf tapeworm. It is also known as the dwarf tapeworm due to its particularly small size adults are only 1540 mm long.
In this video we can see the movement of an adult of hymenolepis nana, observation under a microscope with the objective of 4x magnifying glass. Hymenolepis worms live in the intestines of rats and are common in warm climates, and are generally found in the feces of rats, which are consumed by their secondary hostsbeetles. The adult structure is 20 to 60 cm long and the mature proglottid is similar to that of h. Transmission of hymenolepiasis stanford university. Alternative names are dwarf tapeworm infection and rat tapeworm infection. Transactions of the royal society of tropical medicine and hygiene 101. Hymenolepiasis is prevalent throughout the world with human infections with h. Hymenolepiasis is more frequent among children, and most human infections remain asymptomatic and selflimited. Clinicopathological studies on spontaneous hymenolepis. The species name nana is derived from its small size which means dwarf of the adult worm.
Hymenolepis nana, a tiny intestinal tapeworm, is one of the most common human cestodes. It is the smallest and only cestode that parasites the human without any intermediate host. Hymenolepis nana is an intestinal cestode causing tapeworm infection in humans with a worldwide distribution. Larval and adult beetles but optional larval stage, cysticercoid, can develop in d.
Hymenolepis nana dwarf tapeworm infection infectious. The worms mature into a life form referred to as a cysticercoid in the insect. As mentioned above, hymenolepis nana does not require an intermediate host to complete its life cycle. Apr 20, 2015 hymenolepiasis is the most common intestinal tapeworm infection of humans caused by worm of family cestoda, genus hymenolepis and species nana. Hymenolepis nana, the dwarf tapeworm, is the smallest tapeworm found in the intestines of broad range of dogs, rats and humans.
Laboratory diagnostic of hymenolepis nana dwarf tapeworm. Malignant transformation of hymenolepis nana in a human host to the editor. Hymenolepis nana, also known as dwarf tapeworm, is a cyclophyllidean tapeworm with embryonated eggs. Development hymenolepis nana life cycle infection is acquired most commonly from eggs in the feces of another infected individual, which are transferred in food, by contamination. In the southeastern usa, as many as 1% of young schoolchildren. Larval and adult beetles but optional larval stage, cysticercoid, can develop. It has a cosmopolitan distribution and is thought to be the most common tapeworm throughout the world. Differential diagnosis and molecular characterization of. Hymenolepis nana is one of the most common tapeworms a helminth with a flat, ribbonlike, segmented body. Malignant transformation of hymenolepis nana in a human host. Hymenolepis nana infection is observed in households with poor hygiene and overcrowding, and can have a prevalence of 525% in children 54.
Hymenolepis nana, the dwarf tapeworm, is the smallest tapeworm to infect humans. Rodents are the primary definitive hosts, and grain beetles, fleas, or other insects feed on contaminated rodent droppings as intermediate. The aim of this study was to determine the prevalence in a health area of southern spain. Humans, rodents most common tapeworm of humans in the world 1% rate of infection in the southern u. Only the murine rat tapeworm, hymenolepis diminuta, is used in helminthic therapy and this generally does not reach adulthood in humans so requires regular dosing of hdc.
However, this parasite may be present in a number of other animal transport hosts, such as fleas, beetles, rats and house mice. The adult worm resides in the ileal portion of the small intestine. Prevalence of giardia intestinalis and hymenolepis nana in afghan refugee population of mianwali district, pakistan. The dwarf tapeworm was found in man for the first time by bilharz, in cairo, egypt, in 1851. In this article we will discuss about hymenolepis nana. Drugs used to treat dwarf tapeworm infection hymenolepis nana the following list of medications are in some way related to, or used in the treatment of this. Hymenolepiasis is infestation by one of two species of tapeworm. What is hymenolepis nana infection the dwarf tapeworm or hymenolepis nana is found worldwide. For precise diagnosis of the species, molecular techniques such as pcr and rflp of the nuclear ribosomal internal transcribed spacer 2 rdnaits2 gene marker were carried out. Given the widespread distribution and medical implication of members of the genus hymenolepis, specific identification of the aetiological agent becomes imperative. It is the only cestode that does not require an intermediate host to develop into its infective stage.
Review of dwarf tapeworm hymenolepis nana presentations to northern territory nt government healthcare facilities over 12 years. Hymenolepis nana is the most common tapeworm in humans. Diplacanthus manus, hymenolepis nana, hymenolepis murina. Eggs of hymenolepis nana are immediately infective when passed with the stool and cannot survive more than 10 days in the external environment. Radiographic and pathological features of malignant hymenolepis nana anteroposterior and axial ct scans in panels a and b, respectively, show the. It is often referred to as the dwarf tapeworm due to its small size, 24 cm long and only 1 mm wide 1 fig. The fact that an intermediate host is not required in the life cycle was determined in the late 1800s. Hymenolepis nana hymenolepis diminuta valeria chinchilla. It is interesting to note that the cysticercoid larval stage can develop in these hosts when this happens.
741 82 794 228 1064 1243 643 650 188 1567 1375 58 71 1522 1044 1569 1536 1257 497 430 506 1633 1215 1553 1486 276 614 719 238 602 593 36 608 545 843 807 775 673 671 328 1410 554 1472