Gastroduodenal pathology

Question 1

Describe the basic structure of the GI tract

Answer 1

Mucosa - epithelium, lamina propria, muscularis mucosae

Submucosa

Muscularis - circular muscle, longitudinal muscle

Serosa

Question 2

What is pyloric stenosis?

Answer 2

form of obstruction that presents between 3-6 weeks

hypertrophy of circular muscle

Question 3

Commonest presentation of pyloric stenosis

Answer 3

regurgitation
vomiting
O/E = visible peristalsis + palpable mass after feeding

Question 4

Chronic causes of stomach inflammation

Answer 4

Helicobacter-pylori associated
non-helicobacter pylori associated
autoimmune

Question 5

Acute gastritis causes

Answer 5

irritants - smoking, alcohol
drugs - aspirin, NSAIDs, oral steroids
severe stress - burns, trauma, surgery, shock, sepsis
radiation
chemotherapy

Question 6

Complications of acute gastritis

Answer 6

erosions (small ulcers with depth limited to lamina propria)

acute stress ulcers - penetrate muscularis mucosa

Question 7

Describe autoimmune chronic gastritis

Answer 7

autoimmune destruction of specialised glands of the body mucosa
autoantibodies to intrinsic factor and parietal cells
loss of parietal cells leads to achlorhydria
loss of IF leads to B12 deficiency + pernicious anaemia

Question 8

Compare acute stress ulcer and chronic peptic ulcer

Answer 8

acute stress ulcer:
- does not penetrate muscularis propria
- no scarring under ulcer
- no endarteritis obliterans
- heals by regeneration
- anywhere + multiple

chronic peptic ulcer:
- penetrates muscularis propria
- scarring under ulcer
- endarteritis obliterans
- heals by repair with fibrous scar
- single and usually antral`

Question 9

Compare gastric ulcers and duodenal ulcers

Answer 9

gastric ulcer:
- 40-50
- low or normal acid eroding mucous membrane with reduced resistance
- no genetic factors
- ulcer pain brought on by eating

duodenal ulcer:
- 30-40
- high acid eroding a normal mucous membrane
- genetic factors important
- ulcer pain relieved by eating

Question 9

Histology of a peptic ulcer

Answer 9

4 zones:
- surface layer of necrotic debris
- cellular inflammatory layer rich in neutrophil polymorphs
- granulation tissue layer
- layer of fibrosis

Question 9

What is Zollinger Ellison syndrome?

Answer 9

a condition in which a gastrin-secreting tumour or hyperplasia of the islet cells in the pancreas causes overproduction of gastric acid, resulting in recurrent peptic ulcers

Question 10

What syndrome can gastrinomas be associated with?

Answer 10

MEN1

Question 11

What is a polyp?

Answer 11

any raised lesion above the mucosa