GI Flashcards
What are the anatomic and motor disorders of the oesophagus
- Stenosis- congenital or acquires- progressive dysphasia due to stricture
- Atresia (oesophagus not developed properly) /fistula - newborn with aspiration, pneumonia/ rest distress
- Perforation- acquired, traumatic- results in mediastinitis
- Achalasia - dysmotility of lower 1/3 and proximal dilation - stasis of food causes inflammation - predisposed to SCC of oesophagus
- Varicies- increased portal venous HTN- Dilated submucosal veins at portosystemic anastamosis
What are the features of oesophagitis
- Commonest is reflux oesophagitis
- Caused by regurgitation of gastric content into lower oesophagus -GORD
- Incompetent lower oesophageal sphincter, increased intrabdominal pressure
- Heart burn, dysphagia
Complications:
Ulceration - inflam and necrosis of squamous epithelium
Stricture and stenosis- chronic inflam and fibrosis
Barrett’s metaplasia- replacement of stratified squamous epithelium with columnar mucosa
Describe the features of Barretts oesophagus
- Metaplastic columnar mucosa - red on endoscopy
- Squamous mucosa changes to columnar
Name an infectious type of oesophagitis
- Candida
- more common in diabetes/ immunocompromised
- White plaques on endoscopy with hyphae
Discuss herpes oesophagitis and eosinophilic oesophagitis
Herpes- Associated with odynophagia- pain drinking hot and cold liquids
- Usually in immunocompromised - leukaemia, lymphoma
- Punched out ulcers
Eosinophilic- Eosinophilia in blood, concentric ring in trachea
-Common in young men
What are the two main types of oesophageal cancer
-Squamous carcinoma (middle 1/3) and Adenocarcinoma (distal 1/3)
SCC- most common type
Risk factors -alcohol and tobacco, Dietary fungi, achalasia, genetics
3 patterns
1. Necrotising malignant ulcer
2. Polypoid luminal mass
3. 3 Diffuse neoplasms causing stricture
Adenocarcinoma- on the rise in west - obese middle aged white men
Risk factors - GORD, obesity , barretts oesophagus, alcohol tobacco
Affects distal 1/3 with similar patterns to SCC
How do doctors deal with Barrets metaplasia
- Endoscopic surveillance to detect dysplastic change
- If dysplastic change- radio frequency ablation of barretts mucosa
-Many patients only present when disease is very advanced
How is oesophageal cancer staged
-By depth and invasion of primary tumour through wall
T3 = invasion of muscular propria
pT3 N1 is most common stage that patients present at- invasion through oesophageal wall and into lymph nodes and perioesophageal tissues - may also have mets - present with dysphasia and weight loss
Advanced pt3 Ni - chemo then surgery or chemo and radio / stenting
What causes acute/ erosive gastritis
- NSAIDS/ ferrous sulphate
- Alcohol
- Ingestion of corrosives
- Cancer chemo
- Uraemia
- Severe stress/ shock
- Ischaemia
What are the causes of chronic gastritis
Type A - auto-immune lymphocytic, pernicious anaemia
Type B- chronic active gastritis due to H.pylori (gram neg rod colonises gastric muscosa, secretes urease and brings on inflam reaction - ammonia breath test)
Type C - mucosal injury and regenerative change- reflux of bile or drug exposure (NSAIDS and alcohol)
What are the complications of H. Pylori infection
-Gastritis
-Peptic ulcers , duodenal and gastic ulcers (if infection is in antrum of stomach)
-Atrophy, intestinal metaplasia- body of stomach infection
-Gastric carcinoma
-Gastric lymphoma
-Bleeding - haematemasis or melaena
-Perforation
Scarring/ stenosis of pylorus
Types of Gastric carcinoma and their features
-Intestinal type carcinoma - lymphovascular spread and vascular, hepatic mets more likely to form one tumour compared to other type
-Diffuse type gastric carcinoma- involvement of stomach wall causing linitis plastic (when stomach wall becomes rigid)
Associated with peritoneal spread and mets - ovarian tumours
- Weight loss, anorexia , epigastric mass
- Mets of Virchows node
- Spread to ovaries- Krunkenberg tumours contraindicaton for surgery
What causes gastric lymphoma
- Longstanding H. pylori infection leading to accumulation of lymphoid follicles
- MALT - mucosa associated lymphoid tissue - can progress to low grade malignant lymphoma
- Eradication of H.pylori at this stage can cause lymphoma regression , some can’t
What are GI stromal tumours
- mesenchymal spindle tumours
- Stomach and bowel particularly affected
- Big ones= malignant- Dumbell shaped
- Can cause liver mets
- CD117 tyrosine kinase defect
- Imatininb inhibits tyrosine kinase ans is used to treat
Discuss the features of a small intestine adenocarcinoma
- Less common than colonic adenocarcinoma
- Usually sporadic
- Common sites are duodenal (associated with FAP) and jejunum (napkin ring stricture)
- Many associated with Crohn’s or coeliac
- Often present late - poor prognosis