pathology of the gut

Question 1

what is Barrett’s oesophagus?

Answer 1

distal oesophagus is lined by columnar cells due to metaplasia; the oesophagus is lined by gastric mucosa which can develop goblet cells in another process termed intestinal metaplasia

Question 2

what are the risk factors of Barrett’s oesophagus?

Answer 2

• high BMI
• alcohol drinking
• tobacco smoking
• drugs which relax the lower oesophageal sphincter
• familial/genetic predisposition

Question 3

what happens with Barrett’s oesophagus?

Answer 3

reflux of acidic contents from the stomach into the oesophagus leads to reflux oesophagitis

Question 4

what is the cell change that occurs with Barrett’s oesophagus?

Answer 4

changes from squamous epithelium to columnar epithelium

Question 5

what is the process that changes the cell type in the oesophagus with Barrett’s oesophagus?

Answer 5

metaplasia

Question 6

what is the metastatic process?

Answer 6

an adaptation to injury caused by the gastric contents

Question 7

what process does columnar epithelium increase the risk of adenocarcinoma?

Answer 7

precancerous stage called dysplasia

Question 8

what are the 6 stages of Barrett’s associated carcinoma?

Answer 8

1) squamous epithelium
2) reflux oesophagitis
3) gastric epithelium
4) intestinal metaplasia
5) low grade dysplasia
6) high grade dysplasia

Question 9

what are the 3 histological features of normal large bowel mucosa?

Answer 9

1) the crypts are arranged in a row of reminiscent of test tubes
2) the goblet cells are full of mucin
3) the crypts are separated by the lamina propria with vessels and connective tissue

Question 10

what are the risk factors for dysplasia in ulcerative colitis?

Answer 10

• ulcerative colitis at an early age
• total ulcerative colitis involving the whole large bowel
• repeated bouts of acute inflammation with short periods of remission
• long duration with ulcerative colitis; patients with total ulcerative colitis for 8 years require annual surveillance colonoscopy to look for dysplasia

Question 11

what is diverticular disease?

Answer 11

outpouching as a result of herniation of the mucosa and submucosa through the bowel wall at sites of weakness

Question 12

what population is diverticular disease most common?

Answer 12

those on a low fibre diet

Question 13

what area does 95% of diverticular disease affect?

Answer 13

sigmoid colon

Question 14

what complicated diverticular disease?

Answer 14

• diverticulitis
• perforation
• peritonitis

Question 15

what can present with diverticular disease?

Answer 15

• intestinal obstruction
• can mimic cancer
• colo-vesical fistula
• pneumaturia

Question 16

what does faecal impaction and inflammation lead to?

Answer 16

perforation and peritonitis