Small Bowel Disorders Flashcards
What are differentials for Angiodyplasia?
- GI malignancies
- Diverticular Disease
- Oesophageal Varices
- Coagulopathies
What is Angiodysplasia?
Most common vascular abnormality of GI tract.
Responsible for GI bleeds.
What is the pathophysiology of Angiodysplasia?
- Caused by formation of arteriovenous malformation between previously healthy blood vessels, most commonly caecum and ascending colon.
- Can be divided into acquired and congenital
What is Acquired Angiodysplasia?
- Begins as reduced submucosal venous drainage in colon due to chronic and intermittent contraction of the colon, giving rise to dilated and tortuous veins.
- Results in loss of pre-capillary sphincter competency and in turn causes the formation of small arterio-venous communication characterized by small tuft of dilated vessels.
What is Congenital Angiodysplasia?
-Hereditary haemorrhagic telangectasia (Rendu-Osler-Weber syndrome) or Herde’s syndrome
What are clinical features of Angiodysplasia?
- Rectal bleeding which can be haemorrhagic or painless occult bleeding
- Anaemia
What are tests for Angiodysplasia?
- FBC’s
- U&E’s
- LFTs
- Clotting
- Group and Save or Crossmatch
What imaging tests for Angiodysplasia?
- Upper GI endoscopy performed or colonoscopy
- In small bowel, wireless capsule endoscopy used with any produce bleeding stemmed via administration of therapeutic agents
- Mesenteric angiography ordered in setting of overt angiodysplastic bleed. Can involve either radionuclide scanning, CT scanning or MRI scanning to image GI tract vascular supply after radio-opaque contract agent injection into vessels
How is angiodysplasia conservatively managed?
Bed-rest and IV fluid support, along with potential tranexamic acid will provide sufficient management due to the self-limiting nature of the condition
How is Angiodysplasia medically managed?
Endoscopy – usually first line management. Involves subjecting the bleeding vessel to electrical current and argon acting as a safe, cost-effective, successful treatment option. Other endoscopic techniques include monopolar electrocautery, laser photoablation, sclerotomy, and band ligation
Mesenteric Angiography – used for small bowel lesions that cannot treated endoscopically. Procedure involves super-selective catherization and embolization of the vessel that has been demonstrated to be bleeding by extravasation of contrast dye into the bowel lumen form identified angiodysplastic lesion
What is the surgical management of angiodysplasia?
Resection and anastomosis of affected segment of bowel necessary to limit bleeding. Bowel resection in patients with angiodysplasia associated with relatively high mortality thus should only be considered if necessary. Indications are
- Continuation of severe bleeding despite angiographic and endoscopic management
- Severe acute life-threatening GI bleeding
- Multiple angiodysplastic lesions that cannot be treated medically
What are complications of Angiodysplasia?
- Mainly related to the treatment as re-bleeding post therapy is relatively common.
- Endoscopic techniques have small risk of bowel perforation
- Mesenteric angiography carries risk of haematoma formation, arterial dissection, thrombosis and bowel ischaemia
What are neuroendocrine tumours?
-Gastroenterpancreatic neuroendocrine tumours (GEP-NETs) are neuroendocrine tumours arising from neuroendocrine cells in the tubular GI tract and the pancreas all of which have malignant potential.
What are the grades of Neuroendocrine tumours?
Grade 1 – Well differentiated, mitotic count <2 per 10HPF, ki index <3%\
Grade 2 – Well differentiated, mitotic count 2-20 per 10HPF, ki index 3-20%
Grade 3 – Poorly differentiated, mitotic count >20 per 10HPF, ki index >20%
What are risk factors for Neuroendocrine tumours?
Genetics.
Inherited disorders such as Multiple Endocrine neoplasia type 1 (MEN1, von Hippel-Lindau disease, neurofibromatosis and tuberous sclerosis complex
