I left most of this lecture out as it was repeated in better detail in the IBD and CRC lectures later on.
This stuff is just what wasn’t included elsewhere
What is ischaemic enteritis?
Occluded vessel leads to ischaemic lesions in the gut with location depending on the involved vessel
What happens if one of the 3 major vessels of hte gut is occluded?
What happens if one of the gut arteries is occluded gradually?
Very little as it the anastomotic circulation compensates
Ischaemic enteritis can be caused by an arterial thrombosis, embolism or non-occlusive ischaemia. What are some common sources for these?
- Oral Contraceptive
- Dissecting Aneurysm
- Cardiac vegetations
- Acute Atheroembolism
- Cholesterol Embolism
- Cardiac Failure
- Vasoconstrictive drugs
How does the affected part of the gut appear during ischaemic enteritis?
Congestion leads to a dusky blue/purple color and sanguinous mucous in the lumin
- You get Oedema, Interstitial Hemorrhages & vascular dilatation due to congestion
- You also get Sloughing necrosis of the mucosa & within 1-4 days bacteria cause gangrene & perforation due to lack of blood supply causing tissue death.
Chronically you get inflammation, ulceration and fibrosis/strictures.
What is radiation colitits?
Where abdominal irradiation impairs normal proliferative activity of the bowel epithelium
What is the presentation of radiation colitis?
The damage depends on the dose and location
Chronically it mimics IBD
How does radiation colitis appear histologically?
- Nuclear hypertrophy
- Inflammation causing crypt abscesses & eosinophils
Chronically or in large doses it can also cause:
- Arterial stenosis
What causes appendicitis?
Infection - Often via a stomach or other GI infection
Obstruction, most often due to feocolith or enterobius vermicularis (giant roundworm)
Waht is a feocolith?
A stone of faecaes often with calcification caused by faecal impaction.
When it occurs in the appendix its called appendicolith
How does appendicitis present?
Poorly localised colic pain progressing to sharp pain in right iliac fossa N&V Diarrhoea Anorexia Fever
MAnagement of appendicitis?