GI chapter 7 notes

Question 1

35 y/o male, three episodes of vomiting blood. known to have oesophageal varies as a result of alcoholic liver disease.

How has the patient developed varices?

Answer 1

• underlying liver disease increases resistances to portal blood flow
• causing splanchnic vasodilation
• with sodium and water retention
• significant blood flow increase through portal vein
• leads to portal hypertension and consequent oesophageal varices

Question 2

Define portosystemic anastomoses?

Answer 2

connection between veins of portal circulation and those of systemic circulation

Question 3

These clinical features are indicative of what:

• splenomegaly
• ascites
• spider naevi
• caput medusae
• oesophageal varices
• rectal varices

Answer 3

portal hypertension

Question 4

18 y/o female, severe diarrhoea. Oily and foul smelling motions. Crohn’s diagnosis confirmed.

How does damage to terminal ileum cause steatorrhoea?

Answer 4

• terminal ileum is where bile salt reabsorption occurs
• thus malabsorption of bile acids
• leads to bile salt deficiency
• thus impaired fat solubilisation

Question 5

macrocytosis

Answer 5

red blood cells that are larger than normal

Question 6

18 y/o female, severe diarrhoea. Oily and foul smelling motions. Crohn’s diagnosis confirmed.

why might this patient experience macrocytosis?

Answer 6

• terminal ileum absorbs b12
• malabsorption of b12
• vitamin b12 cofactor for DNA synthesis
• less DNA synthesis in erythrocyte
• hence macrocytosis

Question 7

What is Jaundice?

Answer 7

high bilirubin in plasma causes yellowing of sclera, skin and mucosa

Question 8

Pathophysiology of pre-hepatic jaundice?

Answer 8

• increased RBC breakdown
• increased unconjugated serum bilirubin
• bilirubin water insoluble
• can’t be excreted in urine
• intestinal bacteria converts bilirubin into urobilinogen
• this reabsorbed and excreted by kidneys
• thus increased urinary urobilinogen

Question 9

medication for treatment of peptic ulcers

Answer 9

H2 antagonist (ranitidine)
-----> antagonise histamine receptors decreasing H+ secretion

PPI (omeprazole)
—–> inhibits parietal cell

Question 10

what type of bacteria is heliobacter pylori

Answer 10

gram negative bacteria

Question 11

differences seen in histology between Crohn’s and Ulcerative Colitis?

Answer 11

Crohn’s disease - transmural inflammation, granulomas

Ulcerative Colitis - mucosal / submucosal inflammation, crypt abscess

Question 12

36 y/o female with right upper quadrant abdominal pain, on and off fever and chills in past week. yellow discolouration of sclera and skin.

what type of jaundice is this?

Answer 12

post hepatic jaundice

Question 13

pre-hepatic jaundice

Answer 13

excessive haemolysis where liver unable to cope with excess billirubin

• excess unconjugated hyperbilirubinaemia
• reticulocytosis
• anaemia

Question 14

hepatic jaundice

Answer 14

deranged hepatocyte function

• abnormal clotting
• mixed conjugated and unconjugated bilirubin
• increased liver enzymes

Question 15

post-hepatic jaundice

Answer 15

obstruction of the biliary system

• hyperbilirubinaemia
• dark urine
• increase in ALP

Question 16

pathological features seen on microscopy with liver cirrhosis

Answer 16

• presence of regenerating nodules of hepatocytes

- presence of fibrosis

Question 17

gastric ulcer

Answer 17

• associated with weigh loss
• eating aggravates ulcer
• so patients tend to avoid food

Question 18

50 y/o presents with diarrhoea, bloating, weight loss. complains that her stools are bulky, foul smelling, pale and oily.

has a gluten free diet and this has improved.

you decide she requires an endoscopy.

what would you expect to see from the duodenal biopsy?

Answer 18

Coeliac’s disease

• villous atrophy
• T-cell mediated autoimmune disease
• crypt hyperplasia

Question 19

Parietal cells secrete what and why is this important?

Answer 19

• secrete intrinsic factor

- needed for absorption of B12