Upper gastrointestinal pathology Flashcards
Oesophagitis definition
- Inflammation of the oesophagus
- Classification: acute or chronic (depends on aetiology and duration)
Oesophagitis aetiology
- Infectious (not the most common)
- Bacterial, viral (Herpes: HSV1, fungal - candida
- Chemical – most common
- Ingestion of corrosive substances
- Reflux of gastric contents: commonest cause; stomach contents works through sphincter into lower oesophagus, sometimes upper oesophagus
Reflux Oesophagitis definition
- Commonest form of oesophagitis - caused by reflux of gastric acid = gastro-oesophageal or bile = duodeno-gastric reflux
Reflux Oesophagitis risk factors
- Defective lower oesophageal sphincter
- Hiatus hernia
- Increased intra-abdominal pressure
- Increased gastric fluid volume due to gastric outflow stenosis
Two types of Hiatus hernia
- Sliding hiatus hernia = reflux symptoms
- Para-oesophageal hernia = strangulation and reflux
Barrett’s Oesophagus
- Cause: longstanding gastro-oesophageal reflux
- Risk factors: same as reflux, male, Caucasian, overweight
- Squamous replaced by columnar mucosa = glandular metaplasia
- Barret’s goblet cells
Oesophageal Carcinoma
- Squamous Cell Carcinoma – carcinoma of endemic tissue
- Adenocarcinoma – almost always from Barrett’s as glandular tissue shouldn’t be there – most common
- Adenocarcinoma more common in richer countries due to lifestyle
Oesophageal Adenocarcinoma
- Mainly lower oesophagus
- Higher incidence in main: male/female ratio: 7:1 and among Caucasians
Aetiology:
o Barrett’s oesophagus: most originate from this
o Tobacco/Obesity
Oesophageal Squamous Carcinoma
- Location: middle and lower third
- Squamous carcinoma preceded by squamous dysplasia
- Risk factors include tobacco and alcohol, HPV
- Polypoidal, ulcerating and stricturing
TNM system
- T = depth of invasion of the primary tumour (how far through muscularis propria, deeper connective tissue = worse) – grade of tumour
- N = regional lymph nodes
- M = distant metastasis
4 gastric anatomic regions
- Cardia: area around the GO junction
- Fundus: located in the upper part of the body of the stomach
- Body: main part of the stomach
- Antrum: near the pylorus
Acute gastritis
- Usually due to chemical injury
- Drugs e.g. NSAIDS, alcohol, initial response to helicobacter pylori infection
- Effects depend on severity of the injury: can get erosions and haemorrhage
Gastritis type
Organ wide inflammation
- Normal - Balance of aggressive (acid) and defensive forces
- Increased aggression
- Impaired defences
Chronic Gastritis
- Autoimmune - B12 deficiency
- Helicobacter pylori - Increased risk of gastric cancer and MALT lymphoma
Helicobacter pylori
- Infection itself damages the epithelium leading to chronic inflammation of the mucosa (destruction of cells = decreased acid levels)
- Treat with a combination of antibiotics and PPIs
Peptic Ulcer Disease definition
- Localised defect extending at least into submucosa
- Only part of the lining = erosion, full lining = ulcer
Major sites: - First part of duodenum
- Junction of antral and body mucosa
- Distal oesophagus (GOJ)
Peptic Ulcer Disease aetiology
- Anything that increases gastric acid levels:
- H. pylori infection, duodeno-gastric reflux, drugs: NSAIDs, smoking
Acute gastric ulcer histology
- Full thickness coagulative necrosis of mucosa or deeper layers
- Granulation tissue at ulcer floor
Chronic gastric ulcer histology
- Clear cut edges overhanging the base
- Extensive granulation and scar tissue at ulcer floor
Peptic Ulcer Complications
- Perforation = peritonitis
- Penetration into an adjacent organ e.g. liver or pancreas
- Stricturing = hour glass deformity
- Haemorrhage - chronic can lead to anaemia
Most frequent gastric cancer
adenocarcinoma, as columnar epithelium in the stomach
Gastric Adenocarcinoma aetiology
- Diet (smoked/cured meat or fish, pickled vegetables)
- Helicobacter pylori infection (Western mainly)
- Bile reflux (e.g. post Billroth II operation)
- Hypochlorhydria (allows bacterial growth)
Carcinoma of GOJ
- Similar to lower oesophagus carcinoma
- White males
- Association with GO reflux - no association with H pylori/ diet
Carcinoma of gastric body/antrum
- Association with H. pylori/diet - no association with GO reflux
Hereditary Diffuse Type Gastric Cancer (HDGC)
- Germline CDH1/E-cadherin mutation
- Increased risk of other cancers
Coeliac Disease
- Gluten sensitive enteropathy
- Ingestion of gluten containing cereals
- Fairly common - prevalence of 0.5-1%
Pathogenesis of Coeliac Disease
- Immune-mediated reaction to gliadin
- Causes epithelial cells to produce IL-15
- Causes activation of CD8+ intra-epithelial lymphocytes
- Attack tissue transglutaminase on the bowel epithelium
Diagnosis of coeliac disease
- Tissue biopsy is diagnostic - Gold standard test
- Look down microscope to see the effects of the coeliac on the epithelium
- Gluten free diet and take biopsy weeks later to see if improvement
Clinical Features and Associations of Coeliac
- Dermatitis herpetiformis
- Lymphocytic gastritis and lymphocytic colitis
- Coeliac disease is linked with cancer of the small intestine and T cell lymphoma
Treatment of Coeliac
- Gluten-free diet symptomatic = improvement for most patients
- Reduces risk of long-term complications including anaemia, female infertility, osteoporosis, and cancer
Gastric cancer epidemiology
- More common with ageing, male:female = 2:1
- High rates in Eastern Asia/South America/Eastern Europe
Gastric cancer aetiology
- lifestyle factors (75% of cases) – diet (smoked/cured meat, pickled veg.), smoking, alcohol, obesity
- H.pyori, bile reflux and low levels of stomach acid
Gastric cancer pathogenesis
- Depends on location
- GOJ = GO reflux, no association with H.pylori or diet
- Body and antrum = associated with H.pylori and diet, not GO reflux
Gastric cancer types
- Intestinal type = well differentiated, have intestinal architecture e.g. glands
- Diffuse type = poorly differentiated, scattered growth, cadherin mutation
Gastric cancer clinical features
- Dysphagia, weight loss, indigestion, feeling full, vomiting
- If ulcerating = bleeding (haematemesis) and meleana
Gastric cancer treatment
- If early = resection with a clear margin. If advanced = partial or total gastrectomy.
- Often, it has spread further = chemotherapy
- 20% live for 5 years – poor prognosis with gradual increase in survival
