pathology of the GI tract 1

Question 1

What is gastro-oesophogeal reflux a precursor to?

Answer 1

barretts oesophagus

Question 2

What is barretts oesophagus a precursor to?

Answer 2

oesophageal carcinoma

Question 3

What epithelium is the normal oesophagus lined by?

Answer 3

layers of squamous epithelium

Question 4

What is the oesophagus below the diaphragm lined by?

Answer 4

glandular (columnar) epithelium

Question 5

What is oesophagitis?

Answer 5

Inflammation of the oesophagus

Question 6

What are the two classifications of oesophagitis?

Answer 6

Acute and chronic

Question 7

What causes oesophagitis?

Answer 7

infections (mainly in immunocompromised) e.g. viral (HSV1, CMV), fungal (candida), bacterial
chemical e.g. ingestion of corrosive substances, reflux of gastric content (most common cause)

Question 8

What causes reflux oesophagitis?

Answer 8

reflux of gastric acid and/or bile

Question 9

What are the risk factors for reflux oesophagitis?

Answer 9

defective lower oesophageal sphincter
hiatus hernia
increased intra abdominal pressure
increased gastric fluid vol due to gastric outflow stenoisis e.g. tumour

Question 10

What is the leading clinical symptom for reflux oesophagitis?

Answer 10

heartburn - more burning that crushing pain unlike cardiac pain

Question 11

What histological changes occur in reflux oesophagitis?

Answer 11

basal cell hyperplasia
elongation of papillae
scraping off of squamous cells
increase in number of inflammatory cells

Question 12

What are the complications of reflux oesophagitis?

Answer 12

ulceration
haemorrhage (when ulcers goes into sub mucosa)
perforation
benign strictures (due to healing and contraction of scar tissue)
barretts oesophagus

Question 13

What are the risk factors for barretts oesophagus and reflux oesophagitis?

Answer 13

male
caucasian
overweight

Question 14

What is the histology of barretts oesophagus?

Answer 14

extension of sqaumo-columnar junction

squamous mucosa replaced by columnar mucosa = glandular metaplasia

Question 15

What is important about the intestinal type of columnar mucosa in barretts oesophagus?

Answer 15

specialised barretts mucosa
contains goblet cells
used as diagnosis for barrets oesophagus

Question 16

what are the two histological types of oesophageal carcinomas?

Answer 16

squamous cell carcinoma

adenocarcinoma

Question 17

What group of people have higher incidence of adenocarcinomas?

Answer 17

male
Caucasian
smokers
obese
people who has barrets oesophagus

Question 18

What does adenocarcinoma look like?

Answer 18

plaque like
nodular
fungating
ulcerated
depressed
infiltrating

Question 19

What are the risk factors for squamous cell carcinoma?

Answer 19

tobacco
alcohol
nutrition - source of nitrosamines
thermal injury - hot beverages
HPV
male
black ethinicity

Question 20

What are the histological features of squamous dysplasia?

Answer 20

atypical, large nuclei
more mitosis that are atypical and typical which rise
basement membrane not breached = dysplasia

Question 21

What staging is used for oesophageal carcinomas?

Answer 21

TNM

Question 22

What are the causes of chronic gastritis?

Answer 22

Autoimmune
Bacterial infection e.g. h. pylori
Chemical injury
NSAIDS
Bile reflux
alcohol?

Question 23

What are the features of H. pylori and what does it do to the stomach?

Answer 23

damages epithelium therefore chronic inflammation of the mucosa
most common in the antrum
glandular atrophy
replacement fibrosis
intestinal metaplasia

Question 24

What are the complications of H. pylori?

Answer 24

85% have no symptoms
gastric ulcers
duodenal ulcers
these predispose to gastric cancer

Question 25

What is peptic ulcer disease?

Answer 25

ulcers in the stomach extending at leas into the submucosa

Question 26

what are the major sites for peptic ulcers?

Answer 26

first part of duodenum junction of antral and body mucosa distil oesophagus

Question 27

What are the major factors that cause peptic ulcers?

Answer 27

``` hyperacidity h. pylori duodeno-gastric reflux drugs (NSAIDs) smoking ```

Question 28

what is the histology of a acute gastric ulcer?

Answer 28

full thickness coagulative necrosis of mucosa/deep layers covered with ulcer slough (necrotic debris, fibrin, neutrophils) granulation tissue on ulcer floor flattening of the mucosa

Question 29

what is the histology of chronic gastric ulcers?

Answer 29

clear cut edges overhanging the base extensive granulation and scar tissue at ulcer floor scarring through gastric wall bleeding

Question 30

What are the complications of peptic ulcers?

Answer 30

haemorrhage (could lead to anaemia) perforation → peritonitis penetration into adjacent organs stricturing → hour glass deformity

Question 31

What tends to cause gastric adenocarcinomas?

Answer 31

``` diet (smoked/cured meat, pickled veg) H. pylori bile reflux hypochlorhydria - allows bacterial growth hereditary ```

Question 32

what is hypochlorhydria?

Answer 32

states where the production of hydrochloric acid in gastric secretions of the stomach and other digestive organs is absent or low

Question 33

Who is most at risk of getting carcinoma of the gastric body/antrum?

Answer 33

those with h. pylori | those with a diet of high salt and low fruit and veg

Question 34

What are the 6 macroscopic subtypes of gastric cancer?

Answer 34

``` superficial exophytic flat/depressed superficial excavated exophytic linitis plastica excavated ```

Question 35

What are the 2 main histological subtypes of gastric cancer and describe them.

Answer 35

diffused type - scattered growth, poorly differentiated, ring cells, worse prognosis intestinal type - tubular, glands, well differentiated, metaplasia

Question 36

What is used to stage gastric cancer?

Answer 36

TNM staging

Question 37

What is coeliac disease also known as?

Answer 37

coeliac sprue | gluten sensitive enteropathy

Question 38

What is coeliac disease?

Answer 38

immune mediated enteropathy caused by ingestion of gluten products as they contain GLIADIN - causes cells to express IL-15 IL-15 causes the activation/proliferation of CD8 and IELs CD8 are cytotoxic and kill enterocytes This causes atrophy of the villi

Question 39

How does the diagnosis of coeliac disease come about?

Answer 39

commonly affects the ages of 30-60 years Difficult to diagnose can often be atypical presentation, silent disease, latent disease or symptomatic

Question 40

What is the treatment for coeliac disease?

Answer 40

gluten free diet

Question 41

How is coeliac disease diagnosed?

Answer 41

serologic tests e.g IgA/IgG | tissue biopsy