Difference between revisions of "Intestinal Arterial Thromboembolism"

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* E.g. '''equine''' [[Salmonellosis|'''salmonellosis''']].
 
* E.g. '''equine''' [[Salmonellosis|'''salmonellosis''']].
 
[[Image:Infaction of the small bowel.jpg|thumb|right|150px|Infarction of the small bowel (Courtesy of Bristol BioMed Image Archive)]]
 
[[Image:Infaction of the small bowel.jpg|thumb|right|150px|Infarction of the small bowel (Courtesy of Bristol BioMed Image Archive)]]
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==== Verminous endarteritis ====
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*Caused by larvae of [[Strongylus vulgaris|''S. vulgaris'']] within the cranial mesenteric artery
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*Also called "verminous aneurism" (misnomer as aneurism = dilatation/thinning of blood vessel wall; also, aneurisms are rare)
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*Wall of artery grossly thickened (organising thrombi, inflammatory responses)
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*Can be detected on rectal palpation
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*Many cases asymptomatic
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*May get embolism → infarction of areas of intestinal wall → colic or chronic ulceration (note: generally good collateral circulation; therefore colic is not inevitable)
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*Aberrant larvae may cause thrombosis in other arteries; e.g. iliac, cerebral, coronary
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*Avermectin/milbemycins or fenbendazole are used to control migrating ''S. vulgaris'' larvae
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===Small Animals===
 
===Small Animals===
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* Similar to that caused by venous congestion.
 
* Similar to that caused by venous congestion.
 
* See sharply delineated dark areas in bowel that are flaccid with loss of tone.   
 
* See sharply delineated dark areas in bowel that are flaccid with loss of tone.   
** These become necrotic followed later by peritonitis.[[Category:Intestine_-_Vascular_Disturbances]]
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** These become necrotic followed later by peritonitis.
[[Category:Intestinal Diseases - Dog]][[Category:Vascular Diseases - Dog]][[Category:Cat]]
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 +
 
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[[Category:Intestine_-_Vascular_Disturbances]]
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[[Category:Intestinal Diseases - Dog]][[Category:Vascular Diseases - Dog]][[Category:Intestinal Diseases - Cat]][[Category:Vascular Diseases - Cat]]
 
[[Category:To_Do_-_Clinical]]
 
[[Category:To_Do_-_Clinical]]
[[Category:Cardiovascular_Disorders_-_Horse]]
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[[Category:Vascular Diseases - Horse]]
[[Category:Small_Intestinal_Disorders_-_Horse]]
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[[Category:Small Intestinal Diseases - Horse]]
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[[Category:Cardiology Section]]

Latest revision as of 16:45, 15 October 2013

  • Non-strangulation infarction.
  • There is often a functional obstruction at point of infarction.
  • Relatively rare as the bowel has a good anastomosing blood supply.
Thrombosis of cranial mesenteric artery caused by Strongylus vulgaris larvae (Courtesy of Bristol BioMed Image Archive)

Horses

  • E.g. Strongylus vulgaris larvae migrating in cranial mesenteric artery in horse
    • Cause arteritis with thickening of wall
      • Due to fibrin and debris deposition and hypersensitivity reaction
    • Leads to vasoconstriction
      • May occlude lumen and encourage thromboemboli.
    • Can cause ischaemic necrosis of a segment of small intestine
    • Is less common now that Strongylus vulgaris infections are declining.
  • E.g. equine salmonellosis.
Infarction of the small bowel (Courtesy of Bristol BioMed Image Archive)

Verminous endarteritis

  • Caused by larvae of S. vulgaris within the cranial mesenteric artery
  • Also called "verminous aneurism" (misnomer as aneurism = dilatation/thinning of blood vessel wall; also, aneurisms are rare)
  • Wall of artery grossly thickened (organising thrombi, inflammatory responses)
  • Can be detected on rectal palpation
  • Many cases asymptomatic
  • May get embolism → infarction of areas of intestinal wall → colic or chronic ulceration (note: generally good collateral circulation; therefore colic is not inevitable)
  • Aberrant larvae may cause thrombosis in other arteries; e.g. iliac, cerebral, coronary
  • Avermectin/milbemycins or fenbendazole are used to control migrating S. vulgaris larvae


Small Animals

  • Especially dogs
  • Road traffic accidents produce and infact in the gut.
  • Renal disease also causes infarction.
    • Particularly nephrotic syndrome.
    • Anticoagulant proteins are lost in the urine, leading to a prothrombic state in the ciruclation.

Pathology

  • Similar to that caused by venous congestion.
  • See sharply delineated dark areas in bowel that are flaccid with loss of tone.
    • These become necrotic followed later by peritonitis.