CP20 - Pathology of GI Tract Flashcards
what is the normal histology of oesophagus?
squamous epithelium
what is the sphincter call at the upper end of oesophagus?
cricopharyngeal sphincter
what is the sphincter call at the bottom of oesophagus?
it is called the gastro-oesophageal junction
what is the normal histology of the area after the gastro-oesophageal junction?
glandular (columnar) mucosa
what is the squamo-columnar junction located?
located at 40 cm from the incisor teeth
what are the 3 layers of the oesophagus?
mucosa, submucosa, muscularis propria
what is oesophagitis?
inflammation of the oesophagus
what is the aetiology of oesophagitis?
infection - bacterial, viral (HSV1, CMV), fungal (candida)
chemical - corrosive substances, reflux of gastric contents
what are the 2 main types of oesophagitis?
acute and chronic
what is the commonest form of oesophagitis?
reflux oesophagitis
what is reflux oesophagitis?
Caused by reflux of gastric acid (gastro-oesophageal reflux) and/or bile (duodeno-gastric reflux)
what are some of the risk factors for reflux oesophagitis?
- Defective lower oesophageal sphincter
- Hiatus hernia
- Increased intra-abdominal pressure
- Increased gastric fluid volume due to gastric outflow stenosis
what is the commonest clinical symptom for reflux oesophagitis?
heartburn
what is the histological changes in reflux oesophagitis?
squamous epithelium will undergo basal cell hyperplasia, elongation of papillae and increase cell desquamation, there is also inflammatory cell infiltration
what are some of the complications for reflux oesophagitis?
ulceration, haemorrhage, perforation, benign stricture (segmental narrowing), Bareet’s oesophagus
what are the causes of Barrett’s oesophagus?
longstanding reflux
what is the macroscopic finding of the Barrett’s oesophagus
Proximal extension of the squamo-columnar junction
what is the histological finding of the Barrett’s oesophagus
Squamous mucosa replaced by columnar mucosa > “glandular metaplasia”
what are the different types of columnar mucosa?
gastric cardia, gastric body, intestinal type
what type of columnar mucosa is characteristic for Barrett’s mucosa
intestinal type - normally only found in the stomach
what is barett’s disease premalignant condition of
adenocarcinoma
what is the pathological progression from barett’s disease?
BO - low-grade dysplasia - high- grade dysplasia - adenoma
what are the 2 main types of oesophageal carcinoma?
squamous cell carcinoma (native squamous cells), adenocarcinoma (arise from barrett’s)
what are some of the risk factors oesophageal adenocarcinoma?
Male, caucasians, industrialised countries