ISCHAEMIC BOWEL DISEASE (Robbins pp 820)

Ischaemic bowel disease has three types of severity:

1) mucosal infarction: lesion extends no further than muscularis mucosa,

2) mural infarction: mucosa + submucosa affected,

3) transmural infarction: all visceral layers. Transmural infarcts are usually due to mechanical obstruction of blood vessel, while the others are more due to acute hypoperfusion.

Predisposing factors:

1) arterial thrombosis,

2) arterial embolism,

3) venous thrombosis,

4) non-occlusive,

5) other (i.e.: radiation, herniation etc).

Microscopy: Depends on the type of infarct and the time frame. Transmural: hemorrhagic infarct with necrosis and gangrene aided by bacteria, mural/mucosal: superficial epithelium is necrosed, with sparing of base of crypts.

Clinical features: 50-75% mortality. Transmural infarction: sudden severe abdominal pain, nausea, vomiting, bloody diarrhea. Mural/Mucosal: abdominal pain with intermittent diarrhea.

RADIATION COLITIS

Basically, exposure to radiation will damage the walls of the blood vessels of the gut. This will impose vascular compromises, producing ischaemic bowel changes.

Category: Pathology Notes