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| {{Infobox_Disease | | | __NOTOC__ |
| Name = Ancylostomiasis |
| | {{Ancylostomiasis}} |
| Image = |
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| Caption = |
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| DiseasesDB = |
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| ICD10 = {{ICD10|B|76|0|b|65}} |
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| ICD9 = {{ICD9|126.9}} |
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| ICDO = |
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| OMIM = |
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| MedlinePlus = |
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| eMedicineSubj = ped |
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| eMedicineTopic = 96 |
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| MeshID = D000724 |
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| }} | |
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| ==Overview==
| | {{CMG}} {{AE}} {{Kalpana Giri}} |
| '''Ancylostomiasis''' (also '''anchylostomiasis''' or '''ankylostomiasis''') is a [[hookworm disease]] caused by infection with [[Ancylostoma]] [[hookworm]]s. The name is derived from Greek ancylos αγκυλος "crooked, bent" and stoma στομα "mouth."
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| Ancylostomiasis is also known as '''miner's anaemia''', '''tunnel disease''', '''brickmaker's anaemia''' and '''Egyptian chlorosis'''. [[Helminthiasis]] may also refer to ancylostomiasis, but this term also refers to all other [[parasitic worm]] diseases as well. In the United Kingdom, if acquired in the context of working in a mine, the condition is eligible for Industrial Injuries Disability Benefit. It is a prescribed disease (B4) under the relevant legislation.§<ref>https://www.gov.uk/government/publications/industrial-injuries-disablement-benefits-technical-guidance/industrial-injuries-disablement-benefits-technical-guidance</ref>
| | ==[[Ancylostomiasis overview|Overview]]== |
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| Ancylostomiasis is caused when hookworms, present in large numbers, produce an [[iron deficiency anemia]] by sucking blood from the host's intestinal walls.
| | ==[[Ancylostomiasis historical perspective|Historical Perspective]]== |
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| ==Signs and symptoms== | | ==[[Ancylostomiasis classification|Classification]]== |
| In children (or adults) who walk barefoot, the hookworm can penetrate the sole
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| of the foot and cause a lesion. The larva will then begin to mature while it
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| moves towards the intestines. As in dogs, the hookworm will attach to the
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| intestinal wall. Humans who have become infected will show symptoms of
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| intestinal bleeding, abdominal pains, anemia, severe diarrhea and malnutrition.
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| <ref> {{cite web | url=http://www.essortment.com/all/hookwormdogshu_rdhu.htm |
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| title=Hookworms in dogs and humans | accessdate=2008-10-30 }} </ref>
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| As mentioned earlier larval migrans or as it is also known, creeping eruption,
| | ==[[Ancylostomiasis pathophysiology|Pathophysiology]]== |
| is also a very uncomfortable symptom of this disease, and can also be caused
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| by invasion of hookworms from other animals such as cats and dogs. Because
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| they are in an abnormal host they do not mature to adults but instead migrate
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| through the skin until killed by the host's inflammatory response. This causes
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| local intense itching. Topical treatment with thiabendazole ointment is very
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| effective in controlling this condition.
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| ==Causes== | | ==[[Ancylostomiasis causes|Causes]]== |
| The infection is usually contracted by persons walking barefoot over
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| contaminated soil. In penetrating the skin, the larvae may cause an allergic
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| reaction. It is from the itchy patch at the site of entry that the early
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| infection gets its nickname "ground itch". Once larvae have broken through the skin,
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| they enter the bloodstream and are carried to the lungs (unlike ascarids,
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| however, hookworms do not usually cause pneumonia). The larvae migrate from
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| the lungs up the windpipe to be swallowed and carried back down to the
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| intestine. If humans come into contact with larvae of the dog hookworm or the
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| cat hookworm, or of certain other hookworms that do not infect humans, the
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| larvae may penetrate the skin. Sometimes, the larvae are unable to complete their
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| migratory cycle in humans. Instead, the larvae migrate just below the skin
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| producing snake-like markings. This is referred to as a creeping eruption or
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| cutaneous larva migrans.
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| <ref> {{cite web |
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| url=http://www.comeunity.com/adoption/health/parasites/hookworm-NIH.html |
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| title=Hookworm | accessdate=2008-10-30 }} </ref>
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| ==Diagnosis== | | ==[[Ancylostomiasis differential diagnosis|Differentiating Ancylostomiasis from other Diseases]]== |
| They commonly infect the skin, eyes, and viscera in humans.
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| * [[Ancylostoma brasiliensis]] causes [[cutaneous larva migrans]].
| | ==[[Ancylostomiasis epidemiology and demographics|Epidemiology and Demographics]]== |
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| * [[Toxocara]] causes [[visceral larva migrans]].<ref> {{cite web | url=http://cancerweb.ncl.ac.uk/cgi-bin/omd?larva+migrans | title=Definition: larva migrans | accessdate=2008-10-30 }} </ref>
| | ==[[Ancylostomiasis risk factors|Risk Factors]]== |
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| ==Prevention== | | ==[[Ancylostomiasis natural history, complications and prognosis|Natural History, Complications and Prognosis]]== |
| Control of this parasite should be directed against reducing the level of
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| environmental contamination. Treatment of heavily infected individuals is one
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| way to reduce the source of contamination (one study has estimated that 60% of
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| the total worm burden resides in less than 10% of the population). Other
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| obvious methods are to improve access to [[sanitation]], e.g. [[toilets]], but also
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| convincing people to maintaining them in a clean, functional state, thereby making
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| them conducive to use.
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| == Epidemiology == | | ==Diagnosis== |
| Hookworms still account for high proportion of
| | [[Ancylostomiasis history and symptoms| History and Symptoms]] | [[Ancylostomiasis physical examination | Physical Examination]] | [[Ancylostomiasis laboratory findings|Laboratory Findings]] | [[Ancylostomiasis other imaging findings|Other Imaging Findings]] | [[Ancylostomiasis other diagnostic studies|Other Diagnostic Studies]] |
| debilitating disease in the tropics and 50-60,000 deaths per year can be
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| attributed to this disease.
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| <ref>{{cite web | url=http://www.earthtym.net/ref-hookworms.htm |
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| title=Hookworms: Ancylostoma spp. and Necator spp. |
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| accessdate=2008-10-30| archiveurl= http://web.archive.org/web/20081027170740/http://www.earthtym.net/ref-hookworms.htm| archivedate= 27 October 2008 <!--DASHBot-->| deadurl= no}}</ref>
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| ==Treatment== | | ==Treatment== |
| The drug of choice for the treatment of hookworm disease is [[mebendazole]] which
| | [[Ancylostomiasis medical therapy|Medical Therapy]] | [[Ancylostomiasis surgery|Surgery]] | [[Ancylostomiasis primary prevention|Primary Prevention]] | [[Ancylostomiasis secondary prevention|Secondary Prevention]] | [[Ancylostomiasis cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Ancylostomiasis future or investigational therapies|Future or Investigational Therapies]] |
| is effective against both species, and in addition, will remove the intestinal
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| worm Ascaris also, if present. The drug is very efficient, requiring only a
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| single dose and is inexpensive, the perfect drug. However, treatment requires
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| more than giving the anthelmintic, the patient should also receive dietary
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| supplements to improve their general level of health, in particular iron
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| supplementation is very important. Iron is an important constituent of a
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| multitude of enzyme systems involved in energy metabolism, DNA synthesis and
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| drug detoxification.
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| An infection of ''N. americanus'' parasites can be treated by using [[Imidazole|benzimidazoles]], [[albendazole]], and [[mebendazole]]. A blood transfusion may be necessary in severe cases of anemia. Light infections are usually left untreated in areas where reinfection is common. Iron supplements and a diet high in protein will speed the recovery process.<ref>"hookworm disease." Encyclopædia Britannica. 2009. Encyclopædia Britannica Online. 06 Dec. 2009 <http://www.britannica.com/EBchecked/topic/271350/hookworm-disease>.</ref> In a case study involving 56-60 men with ''[[Trichuris trichiura]]'' and/or ''N. americanus'' infections, both albendazole and mebendazole were 90% effective in curing ''T. trichiura''. However, albendazole had a 95% cure rate for ''N. americanus'', while mebendazole only had a 21% cure rate. This suggests albendazole is most effective for treating both ''T. trichiura'' and ''N. americanus''.<ref> Holzer, B. R.; and Frey, F. J. (February 1987). "Differential efficacy of mebendazole and albendazole against Necator americanus but not for Trichuris trichiura infestations". European Journal of Clinical Pharmacology. 32 (6): 635-637. http://www.springerlink.com/content/k000065915k70257/</ref>
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| ==Gallery==
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| <gallery>
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| Image: Hookworm07.jpeg| Unstained micrograph of the Ancylostoma duodenale hookworm's mouth parts; Mag. 125X. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm05.jpeg| This enlargement shows hookworms, Ancylostoma caninum attached to the intestinal mucosa. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm04.jpeg| Micrograph depicting the tail tip of a Strongyloides filariform infective stage larvae on the left, and a hookworm on the right. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm03.jpeg| This micrograph depicts a hookworm (Lt), and a Strongyloides (Rt) filariform infective stage larvae. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm01.jpeg| This child with hookworm shows visible signs of edema, and was diagnosed with anemia as well. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm06.jpeg| The human hookworms include two nematode (roundworm) species, Ancylostoma duodenale and Necator americanus. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| Image: Hookworm02.jpeg| Diagram depicting the various stages in the life cycle of the Strongyloides stercoralis nematode. <SMALL><SMALL>''[http://phil.cdc.gov/phil/home.asp From Public Health Image Library (PHIL).] ''<ref name=PHIL> {{Cite web | title = Public Health Image Library (PHIL) | url = http://phil.cdc.gov/phil/home.asp}}</ref></SMALL></SMALL>
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| </gallery>
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| ==References==
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| {{reflist|2}}
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| [[Category:Parasitic diseases]]
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| {{WH}}
| | ==Case Studies== |
| {{WS}}
| | [[Ancylostomiasis case study one|Case#1]] |