4b.) Pathology of Stomach Flashcards
Define dyspepsia
Upper GI symptoms that are typically present for four or more weeks including abdo pain or discomfort, nausea/vomitting, heartburn or acid reflux
State some common pathologies of stomach
- GORD (gastroesophageal reflux disease)
- Gastritis (acute or chronic)
- Peptic ulcer disease
- Cancer
What do most pathologies of stomach arise from?
Inability of stomach to protect itself
For GORD, state:
- Symptoms
- Triggers
- Consequences
Symptoms
- Chest pain
- Acid taste in mouth
- Cough
Triggers
- Obesity
- Pregnancy
- Hiatus hernia
- LOS function
- Delayed gastric emptying
Consequences
- Nothing
- Oesophagitis
- Strictures
- Barrett’s oesophagus
During pregnancy women can have new or worse GORD; true or false
True, about 50-80%
What does the lower oesophageal sphincter consist of?
- Muscular element
- Right crus of diaphragm
- Angle of entry of oesophagus into stomach
- Intra-abdominal pressure
State possible treatments for GORD
- Lifestyle modifications: lose weight, smaller more frequent meals..
- Pharmacological: antacids, H2 antagonists, PPI (proton pump inhibitors)
- Surgery= fundoplication (rare)
Describe what a hiatus hernia is
Upper part of stomach pushes up through diaphragm into chest region.
Increases risk for GORD as it decreases basal tone of LOS and prevents the normal increase in LOS tone when straining
What is gastritis?
- Inflammation of the stomach mucosa
- Can be acute or chronic
- Symptoms: pain, nausea, vomitting, bleeding
State some possible causes of acute gastritis
How do you treat acute gastritis?
- Heavy use of NSAIDs
- Excess alcohol
- Chemotherapy
- Bile reflux
Treat by removing the irritant
Describe the response of stomach mucosa to an irritant in acute gastritis
- Irritant damages epithelial cells
- Reduction in mucus production
- Mucosa responds by vasodilation (as we know rich bood supply can remove and buffer acid that breaches mucus barrier) becomes oedematous
- Inflammatory cells present (neutrophils)
State three possible causes of chronic gastritis
- Helicobacterpylori infection (MOST COMMON)
- Autoimmune: autoantibodies attack gastric parietal cells which can lead to pernicious anaemia (as parietal cells produce intrinsic factor)
- Chemical/reactive: chronic alcohol abuse, NSAIDS, reflux of bile
Describe how you could differentiate between chronic gastritis caused by helicobacter pyori or autoimmune cause
Helicobacterpylori
- Asymptomatic or similar to acute gastritis
- Other symptoms may develop eg. peptic ulcers, adenocarcinoma, MALT lymphoma
Autoimmune
- Symptoms of anaemia
- Glossitis
- Anorexia
- Neurological symptoms
For helicobacter-pylori state:
- Gram stain
- Shape
- Spread
- Where found
- Virulence factors
- -ve
- helix shape
- Oral to oral/faecal to oral
- Lives in mucus layer
- Virulence:
- Produces urease which allows it to convert urea in stomach into ammonium- this increases pH and helps it survive in stomach
- Flagellum- good motility
Describe why helicobacter-pylori is damaging to the stomach
- Damages epithelia by releasing cytotoxins
- Produces ammonium - ammonia - toxic to epithelium
- Pro-inflammatory -self injury
- Degrages mucus layer
How do you diagnose helicobacter-pylori?
Diagnose:
- urea breath test
- stool antigen test
Treatment:
- proton pump inhibitor
- amoxicillin + (clarithromycin or metronidazole)
Contrast pathological features in acute and chronic gastristis
What happens if you you H-pyrlori colonisation in the antrum?
- Antrum= where G cells are
- Increased gastrin secretion - increased parietal cell acid secretions- duodenal epithelial metaplasia- colonisation in duodenum- duodenal ulceration
What happens if you get H-pylori colonisation in antrum and body?
Asymptomatic
What happens if you get colonisation of H-pylori in body of stomach?
- Atrophic effect which leads to:
- Gstric ulcers
- Intestinal metaplasia- dysplasia- cancer
What is peptic ulcer disease?
Breach in gastric or duodenal mucosa that extends through the muscularis mucosa; it includes stomach and duodenam ulcers
Where are peptic ulcers most commonly found?
Where, in stomach, are gastric ulcers (subdivision of peptic ulcers) most commonly found?
- Peptic ulcers most commonly found in first part of duodenum (3:1)
- Gastric ulcers most common in lesser curve/antrum of stomach
Peptic ulcer disease is heavilyy associated with presence of Helicobacter-pylori, the effects of stomach acid and use of NSAIDs; true or false
True
Do peptic ulcers always arise from high levels of acid?
No. Uclers can develop in people with normal or low levels of acid; rapid gastric emptying or ineffective neutralisation can increase risk for duodenal ulcers as conditions in duodenum become more acidic than what it is adapted for
State 4 causes of peptic ulcer disease
- H-pylori
- NSAIDs
- Smoking (generally ony contributes to relapse)
- Stress (we mean major physiological stress e.g. burns)
Where do chronic ulcers most commonly occur?
At mucosal junctions e.g.:
- Where antrum meets body (on lesser curve)
- Duodenum (where antrum meets small intestine)
Descrie and explain some potential consequences of peptic ulcer disease, consider:
- Morphology of the ulcers
- Affects on structures
Morphology: generally <2cm (but could be 10cm). Base of ulcer is necrotic tissue and the muscularis propria can be replaced by scar tissue.
- Scar tissue- stenosis
- Perforation- peritonitis
- Erosion into adjacent structure e.g. liver, pancreas
- Haemorrhage from vessel in base of ulcer
- Malignancy (RARE)
State some symptoms of peptic ulcer disease
- Epigastric pain
- Burning/gnawing
- Follows meal times
- Often at night (especially DU)
- Haematemesis
- Malena (lead to anaemia)
- Early satiety from repeated scarring
- Weight loss (reluctant to eat due to pain)
Describe the treatment for peptic ulcer disease
- Lifestyle modifications (e.g. smaller meals, not smoking, weight loss etc)
- Stopping any exacerbating medications (e.g. NSAIDs)
- Testing for H-pylori (and removing)
- Proton pump inhibitors
How would you diagnose peptic ulcer disease?
Endoscopy
Describe how proton pump inhibitors work
Inhibit proton pump in parietal cells to reduce stomach acid
What is functional dyspepsia and how is it diagnosed?
Upper GI system symptoms that persist for a month or longer but no structural abnormalities are found. It is only diagnosed by exclusion of all other possibilities
How could you diagnose a perforation?
Chest x-ray and look for air under diaphragm on both sides
How could you treat functional dyspepsia?
- H2 receptor blockers (cimetidine, rantidine)
- Proton pump inhibitors (omeprazole)
Describe Zollinger-Ellison syndrome
Non-beta islet cell gastrin secreting tumour of pancreas; leads to:
- Proliferation of parietal cells
- Lots of acid production
- Severe ulceration- pain, diarrhoea
What is meant by stress related mucosal damage and state some conditions which may precede it
Broad term used to describe spectrum of pathology attributed to acute, erosive, inflammatory insult to upper GI tract associated with critical illness e.g.:
- Sepsis
- Severe burns
- Raised intracranial pressure
- Severe trauma
- Multi-organ failure
How common is stomach cancer?
3rd most common in world
High rates in Chile/Japan/South America
State some symptoms of stomach cancer
- Dysphagia
- Loss of apeptie
- Malaena
- Weight loss
- Nausea
- Vomitting
- Virchow’s nodes (lymphadenopathy in left supraclavicular node)
Usually presents late
State some risk factors for stomach cancer
- Age
- Male
- H-pylori
- Dietary factors
- Smoking
What parts make up the lower oesophageal sphincter/what does it consist of?
LOS consists of:
- Muscular element
- Right crus of diaphragm
- Angle of entry of oesophagus into stomach
- Intrabdominal pressure (when intrabdominal pressure rises diaphragm flattens)
