View source for Medicine:Alveolar hydatid disease

{{Infobox medical condition (new)
| name          = Aveolar Hydatid Disease
| synonyms      = '''Alveolar echinococcosis''' '''Alveolar colloid of the liver,''' '''Alveolococcosis,''' '''[[Biology:Locule|Multilocular]] echinococcosis'''
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| causes        = infection of larval stage [[Biology:Echinococcus multilocularis|Echinococcus multilocularis]]
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'''Alveolar hydatid disease''' ('''AHD''') is a form of [[Medicine:Echinococcosis|echinococcosis]], or a disease that originates from a [[Biology:Parasite|parasitic]] [[Biology:Flatworm|flatworm]]. AHD is caused by an infection of the flatworm species ''[[Biology:Echinococcus multilocularis|Echinococcus multilocularis]]''.<ref>{{cite journal | vauthors = Wilson JF, Rausch RL, Wilson FR | title = Alveolar hydatid disease. Review of the surgical experience in 42 cases of active disease among Alaskan Eskimos | journal = Annals of Surgery | volume = 221 | issue = 3 | pages = 315–23 | date = March 1995 | pmid = 7717785 | pmc = 1234575 | doi = 10.1097/00000658-199503000-00015 }}</ref> Although alveolar echinococcosis is rarely diagnosed in [[Biology:Human|human]]s and is not as widespread as cystic [[Medicine:Echinococcosis|echinococcosis]] (caused by ''[[Biology:Echinococcus granulosus|Echinococcus granulosus]]''), it is also still a serious disease that has a significantly high fatality rate.<ref name=":0">{{cite book | vauthors = Malik AA, ul Bari S | chapter = Alveolar Hydatid Disease | veditors = Malik AA, ul Bari S | title = Human Abdominal Hydatidosis | date = 2019 | pages = 63–72 | publisher = Springer | location = Singapore |doi= 10.1007/978-981-13-2152-8_6 |isbn= 978-981-13-2152-8 | s2cid = 86375680 }}</ref> It is considered one of the most life-threatening helminthic infections humans can have.<ref name=":0" />

It is most prevalent in {{wipe|China}}, Eastern {{wipe|France}}, {{wipe|Switzerland}}, Austria, Bulgaria, [[Place:Turkey|Turkey]], [[Religion:Iran|Iran]], {{wipe|Japan}}, Afghanistan, and {{wipe|Russia}}, and is mostly confined to the Northern hemisphere, south to around the 40th or 45th degree of Northern latitude, save some cases reported in Northern Africa.<ref name=":0" /><ref name=":3">{{cite book | vauthors = Schantz PM | chapter = Echinococcosis (Hydatid Disease)|date=1988 | title = Laboratory Diagnosis of Infectious Diseases|pages=836–849|place=New York, NY|publisher=Springer New York }}</ref><ref>{{cite journal | vauthors = Rausch RL, Wilson JF, Schantz PM | title = A programme to reduce the risk of infection by Echinococcus multilocularis: the use of praziquantel to control the cestode in a village in the hyperendemic region of Alaska | journal = Annals of Tropical Medicine and Parasitology | volume = 84 | issue = 3 | pages = 239–50 | date = June 1990 | pmid = 2222026 | doi = 10.1080/00034983.1990.11812463 }}</ref><ref name=":1">{{Cite journal| vauthors = Ammann RW, Eckert J |date=1996-09-01|title=CESTODES: Echinococcus |journal=Gastroenterology Clinics of North America|language=en|volume=25|issue=3|pages=655–689|doi=10.1016/S0889-8553(05)70268-5|pmid=8863045|issn=0889-8553}}</ref><ref name=":4">{{cite journal | vauthors = Bhatia JK, Ravikumar R, Naidu CS, Sethumadhavan T | title = Alveolar hydatid disease of the liver: A rare entity in India | journal = Medical Journal, Armed Forces India | volume = 72 | issue = Suppl 1 | pages = S126–S129 | date = December 2016 | pmid = 28050091 | pmc = 5192168 | doi = 10.1016/j.mjafi.2015.12.005 }}</ref>

== Signs and symptoms ==
As the larvae grow in the liver, they create lesions.<ref name=":0" /> If untreated, this progresses into abdominal mass and/or pain, [[Medicine:Jaundice|jaundice]], and finally liver failure.<ref name=":5">{{cite journal | vauthors = Torgerson PR, Keller K, Magnotta M, Ragland N | title = The global burden of alveolar echinococcosis | journal = PLOS Neglected Tropical Diseases | volume = 4 | issue = 6 | pages = e722 | date = June 2010 | pmid = 20582310 | pmc = 2889826 | doi = 10.1371/journal.pntd.0000722 | doi-access = free }}</ref>

== Cause ==
AHD is caused by the larval stage of ''E. mulitilocularis'', a species of flatworm found in the [[Earth:Northern Hemisphere|Northern Hemisphere]].<ref name=":0" /> Humans make poor intermediate hosts for the worm, as they play no role in their life cycle.<ref name=":1" /> However, when exposed the worms will still infect them. A major risk factor is when their domesticated [[Biology:Dog|dog]]s and [[Biology:Cat|cat]]s eat wild, infected (typically [[Biology:Arvicolinae|arvicolid]]) [[Biology:Rodent|rodent]]s.<ref name=":1" /><ref name=":2">{{Cite journal| vauthors = Kantarci M, Pirimoglu B, Kizrak Y |date=2014-03-28|title=Diagnostic imaging and interventional procedures in a growing problem: Hepatic alveolar echinococcosis |journal=World Journal of Surgical Procedures|language=en|volume=4|issue=1|pages=13–20|doi=10.5412/wjsp.v4.i1.13|doi-access=free}}</ref><ref>{{cite journal | vauthors = Knapp J, Combes B, Umhang G, Aknouche S, Millon L | title = Could the domestic cat play a significant role in the transmission of Echinococcus multilocularis? A study based on qPCR analysis of cat feces in a rural area in France | journal = Parasite | volume = 23 | pages = 42 | date = 2016 | pmid = 27739398 | pmc = 5782850 | doi = 10.1051/parasite/2016052 }}</ref> Their [[Biology:Feces|feces]] then will contain the worms' eggs, which have fully developed larval worms inside.<ref name=":1" /> Humans become infected after eating food or water contaminated by embryonated [[Biology:Egg|egg]]s, or by handling an infected host like dogs and cats or by skinning infected [[Biology:Fox|fox]]es.<ref name=":2" /><ref>{{Cite book| vauthors = Morris DL, Richards KS |url=https://www.worldcat.org/oclc/24538737|title=Hydatid disease : current medical and surgical management|date=1992|publisher=Butterworth-Heinemann |isbn=0-7506-1379-3|location=Oxford [England]|oclc=24538737}}</ref>

== Pathophysiology ==
Once ingested by humans, "the [[Biology:Oncosphere|oncosphere]]s hatch in the [[Biology:Stomach|stomach]] or [[Biology:Small intestine|small intestine]], become activated, penetrate the epithelial layer, and [[Earth:Migration (ecology)|migrate]] via [[Biology:Blood|blood]] and lymphatic vessels to the visceral organs, primarily the liver, where they develop to another larval stage, the [[Biology:Metacestode|metacestode]]."<ref name=":1" /> The larval growth resembles a slow-moving [[Medicine:Liver tumor|liver tumor]] and it is able to destroy both the liver parenchyma and its function.<ref name=":0" />

== Diagnosis ==
Due to its infiltration into biliary and [[Medicine:Vascular|vascular]] liver tissue, it can be difficult to differentiate AHD and [[Medicine:Liver cancer|liver cancer]].<ref name=":0" />

== Management ==
Early detection and treatment and radical surgery is key to preventing fatality from AHD.<ref name=":0" /> Treatment may include liver resection to remove the larvae and [[Medicine:Chemotherapy|chemotherapy]] using [[Chemistry:Benzimidazole|benzimidazole]]s.<ref name=":5" /> Chemotherapy must continue for many years, sometimes for the remainder of the patient's life.<ref>{{cite journal | vauthors = Torgerson PR, Schweiger A, Deplazes P, Pohar M, Reichen J, Ammann RW, Tarr PE, Halkic N, Müllhaupt B | display-authors = 6 | title = Alveolar echinococcosis: from a deadly disease to a well-controlled infection. Relative survival and economic analysis in Switzerland over the last 35 years | journal = Journal of Hepatology | volume = 49 | issue = 1 | pages = 72–7 | date = July 2008 | pmid = 18485517 | doi = 10.1016/j.jhep.2008.03.023 }}</ref> Failure to comply with these expensive and difficult treatments will likely result in death for the patient.<ref name=":5" />

== Prognosis ==
The disease is often progressive and destructive.<ref>{{cite journal | vauthors = Amir-Jahed AK, Fardin R, Farzad A, Bakshandeh K | title = Clinical echinococcosis | language = en-US | journal = Annals of Surgery | volume = 182 | issue = 5 | pages = 541–6 | date = November 1975 | pmid = 1190858 | pmc = 1344034 | doi = 10.1097/00000658-197511000-00001 }}</ref> The growth happens slow, and so many people do not get symptoms until the later stages.<ref name=":4" /> Central [[Biology:Necrosis|necrotic]] cavities are common in advanced stages of the disease.<ref>{{cite journal | vauthors = Gottstein B | title = Molecular and immunological diagnosis of echinococcosis | journal = Clinical Microbiology Reviews | volume = 5 | issue = 3 | pages = 248–61 | date = July 1992 | pmid = 1498767 | doi = 10.1128/cmr.5.3.248 | pmc = 358243 }}</ref>

== Epidemiology ==
AHD is not as common as diseases caused by other flatworms, but it is still prevalent in the Northern hemisphere. It is not uncommon in China, with some communities having a 5% or more [[Medicine:Infection rate|infection rate]].<ref>{{cite journal | vauthors = Craig PS, Deshan L, MacPherson CN, Dazhong S, Reynolds D, Barnish G, Gottstein B, Zhirong W | display-authors = 6 | title = A large focus of alveolar echinococcosis in central China | journal = Lancet | volume = 340 | issue = 8823 | pages = 826–31 | date = October 1992 | pmid = 1357252 | doi = 10.1016/0140-6736(92)92693-a | s2cid = 31696615 }}</ref><ref>{{cite journal | vauthors = Budke CM, Jiamin Q, Zinsstag J, Qian W, Torgerson PR | title = Use of disability adjusted life years in the estimation of the disease burden of echinococcosis for a high endemic region of the Tibetan plateau | journal = The American Journal of Tropical Medicine and Hygiene | volume = 71 | issue = 1 | pages = 56–64 | date = July 2004 | pmid = 15238690 | doi = 10.4269/ajtmh.2004.71.56 | s2cid = 35630697 | doi-access = free }}</ref> In Europe, it is considered an emerging disease.<ref name=":5" /> The increasing fox populations of [[Earth:Europe|Europe]] correlate with heightened reported cases.<ref>{{cite journal | vauthors = Schweiger A, Ammann RW, Candinas D, Clavien PA, Eckert J, Gottstein B, Halkic N, Muellhaupt B, Prinz BM, Reichen J, Tarr PE, Torgerson PR, Deplazes P | display-authors = 6 | title = Human alveolar echinococcosis after fox population increase, Switzerland | journal = Emerging Infectious Diseases | volume = 13 | issue = 6 | pages = 878–82 | date = June 2007 | pmid = 17553227 | doi = 10.3201/eid1306.061074 | pmc = 2792858 }}</ref>

== History ==
In 1855, Rudolf Virchow, the German pathologist, recognized that the disorder that was at the time known as ''[[Physics:Colloid|colloid]] carcinoma of the liver'', which was known for its tumor-like [[Medicine:Lesion|lesion]]s in the liver, were actually caused by an ''Echinococcus'' species. For 100 year it was debated whether the species was ''E. granulosus'' or a different species. It was finally settled by two publications between 1954 and 1955, the former from [[Earth:Alaska|Alaska]] and the latter from {{wipe|Germany}}.<ref name=":1" />

== Society and culture ==
AHD is confined to the Northern hemisphere.<ref name=":3" /> There are about 18,235 reported cases every year with 95% hailing from {{wipe|China}}.<ref>{{cite journal | vauthors = Nunnari G, Pinzone MR, Gruttadauria S, Celesia BM, Madeddu G, Malaguarnera G, Pavone P, Cappellani A, Cacopardo B | display-authors = 6 | title = Hepatic echinococcosis: clinical and therapeutic aspects | journal = World Journal of Gastroenterology | volume = 18 | issue = 13 | pages = 1448–58 | date = April 2012 | pmid = 22509076 | pmc = 3319940 | doi = 10.3748/wjg.v18.i13.1448 | doi-access = free }}</ref>

== Research directions ==
Wildlife research is working to detect the parasite in new areas.<ref>{{cite journal | vauthors = Romig T, Dinkel A, Mackenstedt U | title = The present situation of echinococcosis in Europe | journal = Parasitology International | volume = 55 Suppl | pages = S187-91 | date = January 2006 | pmid = 16352465 | doi = 10.1016/j.parint.2005.11.028 }}</ref>

== References ==
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== External links ==
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|  DiseasesDB     = 4048
|  ICD10          = {{ICD10|B|67|7|b|LinkMajor}}
|  ICD9           = {{ICD9|122.7}}
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[[Category:Helminthiases]]

{{Sourceattribution|Alveolar hydatid disease|1}}