Español: Representación gráfica del ciclo biológico del parásito cestodo Echinococcus granulosus, indicando los distintos estadios del mismo. Video realizado por alumnos de 2do año de Medicina Humana de la Facultad de Medicina San Fernando (UNMSM) Mesa 2 Grupo A. B) CICLO VITAL DE ECHINOCOCCUS SP from publication: Tissular are parasitic diseases caused by larvae of Taenia solium and Echinococcus sp., DNA damage, RAD9 and fertility/infertility ofEchinococcus granulosus hydatid cysts.
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Human echinococcosis hydatidosis, or hydatid disease is caused by the larval stages of cestodes tapeworms of the genus Echinococcus. Echinococcus granulosus causes cystic echinococcosis, the form most frequently encountered; E. The adult Echinococcus granulosus 3 to 6 mm long resides in the small bowel of the definitive hosts, dogs or other canids.
Gravid proglottids release eggs that are passed in the feces. After ingestion by a suitable intermediate host under natural conditions: The definitive host becomes infected by ingesting the cyst-containing organs of the infected intermediate host. After ingestion, the protoscolices evaginate, attach to the intestinal mucosaand develop into adult stages in 32 to 80 days. The same life cycle occurs with E. Humans become infected by ingesting eggswith resulting release of oncospheres in the intestine and the development of cysts,in various organs.
Echinococcus granulosus occurs practically worldwide, and more frequently in rural, grazing areas where dogs ingest organs from infected animals. Echinococcus multilocularis occurs in the northern hemisphere, including central Europe and the northern parts of Europe, Asia, and North America. Echinococcus vogeli and Echinococcus oligarthrus occur in Central and South America. Echinococcus granulosus infections remain silent for years before the enlarging cysts cause symptoms in the affected organs.
Hepatic involvement can result in abdominal pain, a mass in the hepatic area, and biliary duct obstruction. Pulmonary involvement can produce chest pain, cough, and hemoptysis. Rupture of the cysts can produce fever, urticaria, eosinophilia, and anaphylactic shock, as well as cyst dissemination. In addition to the liver and lungs, other organs brain, bone, heart can also be involved, with resulting symptoms.
Echinococcus multilocularis affects the liver as a slow growing, destructive tumor, with abdominal pain, biliary obstruction, and occasionally metastatic lesions into the lungs and brain. Echinococcus vogeli affects mainly the liver, where it acts as a slow growing tumor; secondary cystic development is common. Image taken at x magnification.
Cross-section of an E.
The cyst wall is composed of an acellular laminated external layer green arrow and a thin, germinal nucleated inner layer yellow arrow. Note the brood capsule black arrow with protoscoleces blue arrows inside. Image taken at 40x magnification. Higher magnification x of the cyst in Figure C, showing daughter cyst brood capsule. Note the hooklets purple arrow inside one of the protoscoleces and the calcareous corpuscles light blue arrows along the germinal layer. Degenerating protoscolex from a liver cyst, stained with PAP.
Notice the conspicuous calcareous corpuscles, characteristic of cestode infections. Higher magnification x of the specimen in Figure A. Notice a pair of refractile hooks yellow arrows. Higher magnification x of the specimen in Figure C. Notice the refractile hook green arrow. Egg of Echinococcus sp. Close-up of the scolex of E. In this focal plane, one of the suckers is clearly visible, as is the ring of rostellar hooks. In seronegative patients with hepatic image findings compatible with echinococcosis, ultrasound guided fine needle biopsy may be useful for confirmation of diagnosis; during such procedures precautions must be taken to control allergic reactions or prevent secondary recurrence in the event of leakage of hydatid fluid or protoscolices.
Immunodiagnostic tests can be very helpful in the diagnosis of echinococcal disease and should be used before invasive methods. However, the clinician must have some knowledge of the characteristics of the available tests and the patient and parasite factors associated with false results. False-positive reactions may occur in persons with other helminthic infections, cancer, and chronic immune disorders.
Negative test results do not rule out echinococcosis because some cyst carriers do not have detectable antibodies.
Whether the patient has detectable antibodies depends on the physical location, integrity, and vitality of the larval cyst. Cysts in the liver are more likely to elicit antibody response than cysts in the lungs, and, regardless of localization, antibody detection tests are least sensitive in patients with intact hyaline cysts.
Cysts in the lungs, brain, and spleen are associated with lowered serodiagnostic reactivity, whereas those in bone appear to more regularly stimulate detectable antibody. Fissuration or rupture of a cyst is followed by an abrupt stimulation of antibodies.
A patient with senescent, calcified, or dead cysts is generally found to be seronegative. Cystic echinococcal disease Echinococcus granulosus. Crude hydatid cyst fluid is generally employed as antigen. At present, the best available serologic diagnosis is obtained by using combinations of tests.
Antibody responses have also been monitored as a way of evaluating the results of treatment, but with mixed results.
Following successful radical surgery, antibody titers decline and sometimes disappear; titers rise again if secondary cysts develop. Tests for Arc 5 or IgE antibodies appear to reflect antibody decline during the first 24 months postsurgery, whereas the IHA and other tests remain positive for at least 4 years. Chemotherapy has not been followed by consistent declines in antibody titers.
Alveolar echinococcal disease Echinococcus multilocularis. Most patients with alveolar echinococcu have detectable antibodies in gramulosus tests using heterologous E.
With crude Echinococcus antigens, nonspecific reactions create the same difficulties as described above, however, immunoaffinity-purified E.
Comparing serologic reactivity to Em2 antigen with that to antigens containing components of both E. Combining two purified E.
As in cystic echinococcosis, Em2 tests are more useful for postoperative follow-up than for monitoring the effectiveness of chemotherapy. Lightowlers MW, Gottstein B. Echinococcus and hydatid disease. Treatment information for echinococcosis can be found at: DPDx is an education resource designed for health professionals and laboratory scientists.
For an overview including prevention and control visit www. Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to page options Skip directly to site content. Enter Email Address What’s this? Recommend on Facebook Tweet Share Compartir. Parasite Biology Image Gallery Laboratory Diagnosis Treatment Information Parasite Biology Causal Agent Human biolofico hydatidosis, or hydatid disease is caused by the larval stages of cestodes tapeworms of the genus Echinococcus.
Life Cycle The adult Echinococcus granulosus 3 to 6 mm long resides in the small bowel of the definitive viclo, dogs or biologicoo canids. Geographic Distribution Echinococcus granulosus occurs practically worldwide, and more frequently in rural, grazing areas where dogs ingest organs from infected animals.
File:Ciclo biológico Echinococcus – Wikimedia Commons
Image Gallery Echinococcus granulosus biolgico tissue. Dogs and other canids are the definitive hosts for Echinococcus spp. Upon ingestion of the eggs by the human host, the oncospheres migrate from the intestinal lumen to other body sites and develop bioloogico hydatid cysts. These cysts can be found in any part of the body, but are most common in the liver, lung and central nervous system. Protoscoleces liberated from a hydatid cyst.
The following images show the contents of a degenerating hydatid cyst from a liver aspirate, stained with Papanicolaou PAP stain. Protoscoleces in a hydatid cyst removed a liver cyst, stained with PAP. Higher magnification of the image in Figure C, showing a close-up of the hooklets.
Free hooklets in ‘hydatid sand’ from the aspirate of a liver cyst, stained with PAP. Echinococcus multilocularis is the second most common cause of echinococcosis in humans. The definitive hosts for E. Arvicoline rodents also play an important role in the natural life cycle.
Echinococcus eggs in feces.
File:Ciclo biológico Echinococcus granulosus.jpg
As dogs and other canids are the definitive hosts for Echinococcus spp. Eggs are however indistinguishable from the eggs of Taenia spp. The internal oncosphere contains 6 refractile hooks.
As dogs and other canids are the only definitive hosts for Echinococcusadults are not expected to be found in the human host.
Adults range from mm in length and usually consist of a scolex and three proglottids. The third terminal proglottid is gravid and is longer than wide. The scolex contains four suckers and a rostellum with hooks.
Echinococcus granulosus adult, stained with carmine.
Antibody Detection Immunodiagnostic tests can be very helpful in the diagnosis of echinococcal disease and should be used before invasive methods. Treatment Information Treatment Information Treatment information for echinococcosis can be found at: Get Email Updates To receive email updates about this echinociccus, enter your email address: November 9, Page last updated: November 9, Content source: Linking to a non-federal site does not constitute an endorsement by HHS, CDC or any of its employees of the sponsors or the information and products presented on the site.