Lower GI bleed

Question 1

Differential diagnosis lower gi bleed? (14)

Answer 1

Large bowel
Anus: anal fissure, haemorrhoids, anal cancer
Rectum: rectal varices, rectal ulcer, rectal cancer
Colon:
-diverticular disease (bleeding diverticulosis)
- Angiodysplasia (capillary, cavernous haemangioma), AV malformations
- colitis: infective (bacteria pseudomembranous colitis, virus CMV, parasites amoebic), inflammatory (UC, CD, indeterminate), chemical (NSAIDS, anti-angina eg nicorandil), ischaemic (bleed at watershed area eg splenic flexure), radiation
- colon carcinoma / post-polypectomy bleeding
- dieulafoy’s lesion (most common in stomach 75%, then duodenum 14%, then colon 5%)
- colonic varices, aortocolonic fistula, vasculitis

Small bowel
-angiodysplasia
-ileum: Meckel’s diverticulum (usually dark red blood)
-enteritis/CD, aortoduodenal fistula (synthetic vascular graft)
- jejunoileal diverticula
- neoplasms/ lymphoma

UGIT
-massive UGI bleed eg bleeding D1 ulcer

Question 2

Term for fresh blood seen on toilet paper after defecation or mixed with stools?

Answer 2

Haematochezia

Question 3

Type of gi bleed by diverticulosis?

Answer 3

• Painless haematochezia
• perforating artery adjacent to colonic diverticulum may become attenuated and erode → bright red arterial bleed- torrential bleed that stops spontaneously

Question 4

Most common site colonic bleeding by angiodysplasia?

Answer 4

Right colon

Question 5

Complications lower gi bleed? (3)

Answer 5

• Dehydration and shock: extreme thirst, confusion, pallor, decreased urine output, long capillary refill time, dry tongue..
• symptomatic anaemia: sob on exertion, postural dizzy, syncope, chest pain, palpitation , lethargy/fatigue.

Question 6

Define massive lower gi bleed

Answer 6

Haemorrhage distal to ligament of treitz that needs ≥ 3 units of blood in 24 hours

Question 7

Name 5 causes microcytic anemia

Answer 7

Tails
• thalassaemia (low hb)
• anemia of chronic disease!
• iron deficiency anemia!
• lead poisoning
• sideroblastic anemia (low rBC, too much iron)

Question 8

Name 5 causes normocytic anemia

Answer 8

3 As 2 Hs
. Acute blood loss!
• anemia chronic disease!
• aplastic anemia
• hemolytic anemia
• hypothyroid!

Question 9

Name 7 causes macrocytic anemia

Answer 9

Megaloblastic
• b 12 deficiency
• folate deficiency

Normoblastic
• Alcohol!
• reticulocytosis from haemolytic anemia or blood loss!
• hypothyroid!
• liver disease!
. Drugs like azathioprine