Angiodysplasia
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223458817
2008-07-04T04:27:55Z
Kyle the bot
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robot Adding: [[de:Angiodysplasie]]
{{Infobox_Disease
| Name = {{PAGENAME}}
| Image = Argon plasma coagulation.jpg
| Caption = An '''angiodysplasia''' in the colon being treated with [[argon plasma coagulation]] administered via probe through the colonoscope. The patient had [[Heyde syndrome|multiple colonic angiodysplasiae]] in the setting of [[aortic stenosis]].
| DiseasesDB = 2963
| ICD10 = {{ICD10|K|55|2|k|55}}
| ICD9 = {{ICD9|569.84}}, {{ICD9|569.85}}
| ICDO =
| OMIM =
| MedlinePlus =
| eMedicineSubj = med
| eMedicineTopic = 134
| MeshID = D016888
}}
In [[medicine]] ([[gastroenterology]]), '''angiodysplasia''' is a small [[blood vessel|vascular]] malformation of the [[gut]]. It is a common cause of otherwise unexplained [[gastrointestinal bleed]]ing and [[anemia]]. Lesions are often multiple, and frequently involve the [[cecum]] or [[ascending colon]], although they can occur at other places. Treatment may be with endoscopic interventions, medication, or occasionally surgery.
==Signs and symptoms==
Although some cases present with black, tarry stool ([[melena]]), the blood loss can be subtle, with the anemia symptoms predominating. [[Fecal occult blood]] testing is positive when bleeding is active. If bleeding is intermittent the test may be negative at times.
==Diagnosis==
Diagnosis of angiodysplasia is often accomplished with [[endoscopy]], either [[colonoscopy]] or [[esophagogastroduodenoscopy]] (EGD). Although the lesions can be notoriously hard to find, the patient usually is diagnosed by endoscopy. A new technique, [[Wireless capsule endoscopy|pill enteroscopy]], has been a major advance in diagnosis, especially in the [[small bowel]] which is difficult to reach with traditional endoscopy. With this technique a pill that contains a video camera and radio transmitter is swallowed, and pictures of the small intestine are sent to a receiver worn by the patient.
Angiodysplasiae in the small bowel can also be diagnosed and treated with [[double-balloon enteroscopy]], a technique involving a long endoscopic camera and overtube, both fitted with balloons, that allow the bowel to be accordioned over the camera.<ref name="pmid17981272">{{cite journal |author=Neumann H, Mönkemüller K, Malfertheiner P |title=Obscure overt GI bleeding secondary to angiodysplasias at the hepaticojejunostomy diagnosed and successfully treated with double-balloon enteroscopy |journal=Gastrointest Endosc |volume= 67|issue= |pages=563|year=2007 |pmid=17981272 |doi=10.1016/j.gie.2007.06.051}}</ref>
In cases with negative endoscopic findings and high clinical suspicion, selective [[angiography]] of the [[mesenteric artery|mesenteric arteries]] is sometimes necessary, but this allows for interventions at time of the procedure. An alternative is [[scintigraphy]] with [[red blood cell]]s labeled with a [[radioactive]] marker; this shows the site of the bleeding on a [[gamma camera]] but tends to be unhelpful unless the bleeding is continuous and significant.<ref name="pmid14989574">{{cite journal |author=Mitchell SH, Schaefer DC, Dubagunta S |title=A new view of occult and obscure gastrointestinal bleeding |journal=Am Fam Physician |volume=69 |issue=4 |pages=875–81 |year=2004 |pmid=14989574 |url=http://www.aafp.org/afp/20040215/875.html}}</ref>
==Pathophysiology==
Histologically, it resembles [[telangiectasia]]. Development is related to age and strain on the bowel wall, which is thought to influence the caliber change and proliferation of the vascular tissue.<ref name=Warkentin>{{cite journal |author=Warkentin TE, Moore JC, Anand SS, Lonn EM, Morgan DG |title=Gastrointestinal bleeding, angiodysplasia, cardiovascular disease, and acquired von Willebrand syndrome |journal=Transfusion medicine reviews |volume=17 |issue=4 |pages=272–86 |year=2003 |pmid=14571395|doi=10.1016/S0887-7963(03)00037-3}}</ref>
Although angiodysplasia is probably quite common, the risk of [[bleeding]] is increased in disorders of [[coagulation]]. A classic association is [[Heyde's syndrome]] (coincidence of [[aortic valve stenosis]] and bleeding from angiodysplasia). In this disorder, [[von Willebrand factor]] (vWF) is proteolysed due to high [[shear stress]] in the highly turbulent blood flow around the aortic valve. vWF is most active in vascular beds with high shear stress, including angiodysplasias, and deficiency of vWF increases the bleeding risk from such lesions.<ref name=Warkentin/>
Warkentin ''et al'' argue that apart from aortic valve stenosis, some other conditions that feature high shear stress might also increase the risk of bleeding from angiodysplasia.<ref name=Warkentin/>
==Therapy==
If the anemia is severe, [[blood transfusion]] is required before any other intervention is considered. [[Endoscopy|Endoscopic]] treatment is an initial possibility, where cautery or [[argon plasma coagulation]] (APC) laser treatment is applied through the endoscope. [[Resection]] of the affected part of the bowel may be needed. However, the lesions may be widespread, making such treatment impractical. [[Embolisation]] through [[angiography]] is occasionally contemplated with severely bleeding lesions that cannot be visualised on colonoscopy.
If the bleeding is from multiple or inaccessible sites, systemic therapy with [[medication]] may be necessary. First-line options include the antifibrinolytics [[tranexamic acid]] or [[aminocaproic acid]]. Estrogens can be used to stop bleeding from angiodysplasia. Estrogens cause mild hypercoaguability of the blood. Estrogen side effects can be dangerous and unpleasant in both sexes. Changes in voice and [[gynecomastia|breast swelling]] is bothersome in men, but older women often report improvement of [[libido]] and [[menopause|perimenopausal]] symptoms. (The worries about [[hormone replacement therapy]]/HRT, however, apply here as well.)
In difficult cases, there have been positive reports about [[octreotide]]<ref>{{cite journal |author=Junquera F, Saperas E, Videla S, Feu F, Vilaseca J, Armengol JR, Bordas JM, Piqué JM, Malagelada JR |title=Long-term efficacy of octreotide in the prevention of recurrent bleeding from gastrointestinal angiodysplasia |journal=Am. J. Gastroenterol. |volume=102 |issue=2 |pages=254–60 |year=2007 |pmid=17311647 |doi=10.1111/j.1572-0241.2007.01053.x}}</ref> and thalidomide,<ref>{{cite journal |author=Shurafa M, Kamboj G |title=Thalidomide for the treatment of bleeding angiodysplasias |journal=Am. J. Gastroenterol. |volume=98 |issue=1 |pages=221–2 |year=2003 |pmid=12526972 |doi=10.1111/j.1572-0241.2003.07201.x}}</ref>
In severe cases or cases not responsive to either endoscopic or medical treatment, [[surgery]] may be necessary to arrest the bleeding.
==References==
{{reflist|2}}
{{Gastroenterology}}
[[Category:Gastroenterology]]
[[de:Angiodysplasie]]
[[fr:Angiodysplasie]]
[[zh:小肠血管发育不良]]