Gastric Diseases II Flashcards
What is a peptic ulcer
Break in superficial epithelial lining that penetrates to the muscular mucosa of either the stomach or duodenum (fibrous base and increase in inflammatory cells)
Where are gastric ulcers commonly seen
Lesser curve of the stomach but can be found anywhere on the stomach
Are duodenal ulcers more or less common than gastric
More
What population do ulcers effect
Elderly and developing countries
What causes ulcers in the developing world
HELICOBACTER PYLORI
What gender is increainsgly getting ulcers
Women
Main causes of gastric ulcers
- Helicobacter pylori infection
- Drugs (NSAIDS, steroids and SSRI’s)
- Increased gastric acid secretion
- Smoking
- Delayed gastric emptying
- Blood group O
What disease can ulcers cause
Gastritis
What is the gastric mucosa protected by and what cells secrete it
Mucin
Gastric cells
Name two NSAIDS
Naproxen
Aspirin
What compound stimulates mucus secretion
Prostaglandins
What do NSAIDS inhibit
COX-1 (needed for prostaglandin synthesis)
So causes ulcers
IN what part of the stomach layer are helicobacter pylori found
- Mucous layer
How do helicobacter cause ulcers
- Destory mucin in mucosa
- Decreased duodenal HCO3- production increasing acidity of the stomach as there will be less alkali to buffer the acid
- Secretes urease, splitting yea into CO2 and ammonia
- Ammonia is toxic to gastric mucosa so less mucous is produced
- Secreted proteases, phospholipase and cytotoxin A attack gastric epithelium reducing mucous production
- Results in inflammatory response and less mucosal defence\7. Increases gastrin release (more HCL secretion by parietal cells + trigger release of histamine)
- Increases parietal cell mass = more acid production
- Decreased somatostatin
What three conditions are caused by H. pylori
Inflammation
Gastric cancer
Peptic ulcers
How does ischameia of gastric cells cause peptic ulcers
- Causes gastric cells to produce less mucin resulting in less protection from acid meaning acid is bale to damage mucosa resulting in an ulcer
- Cause day low pressure or atherosclerosis
How do we treat over production of HCL
PPI or H2 blockers
How does alcohol cause peptic ulcers
Direct toxic effect on gastric cells in high conc.
Clinical presentation of peptic ulcer disease
- Patient can point with one finger to the epigastrium as site of pain
- Pain of duodenal ulcers occurs at night and hunger
- Pain in both is relived by antacids
- Nausea, anorexia nd weight loss
red alarms for cancer and not PUD
- Unexplained weight loss
- Anaemia
- Evidence f GI bleeding
- Dysphagia
- Upper abdominal mass
- Persistent vomiting
Complications of a duodenal ulcer
Ulcer can get deeper and deeper unit lit hits an artery (gasproduodenal artery = massive haemorrhage)
Why can ulcers cause peritonitis
Acid enters the peritoneum
How do we diagnose for peritonitis
See air under the diaphragm on erect X-ray
How can an ulcer cause acute pancreatitis
If ulcer hits pancreas
What is the non-invasive test for peptic ulcers
- Serological test
- Breath test
- Stool antigen testing
(if test is positive then treatment ASAP)
When is an endoscopy used for Peptic ulcers
If gastric ulcer is present, needed for re-scope 6-8 weeks later to ensure no malignancy
Donen over 55 and red-alarm for cancer
What are non-invasive H.pylori testing for diagnosis
- Serology
- C-Urea breath test
- Stool antigen test
What are we trying to find in blood tests for H. pylori
- Detects IgG antibodies (not useful for confirming eradication or present of current infection since IgG takes 1 year to fall by 50%)
Pros of C-urea breath test
- Quick + Reliable test for H. Pylori
What is the C-urea breath test
Measures CO2 in breath after ingestion of C-urea
- Used to monitor infection after eradication
- Highly sensitive and specific
- No antibiotics or PPIs before test
What is the stool antigen test
- Immunoassay using monoclonal antibodies for detection of H.pylori
- Monitors efficacy of eradication therapy
- Patients should be off PPIs for 2 weeks before
What is invasive H.pylori testing
ENDOSCOPY
Biopsy urease test:
H.pylori secrete urease so will cause colour change of yellow to red
Why do we not give PPIs or antibiotics in biopsy urease test
Will give false negatives
How do you treat Peptic ulcers
- Reduce stress
- Avoid irritating food
- No smoking
- Stop NSAIDS
- H2 antagonist (CIMETIDINE)
- Surgery
How is H.pylori eradicated
- TRIPLE THERAPY:
PPI (Lansoprazole or Omeprazole)
- plus two of:
- METRONIDAZOLE, CLARITHROMYCIN, AMOXICILLIN, TETRACYCLINE, BISMUTH
- QUINOLONES (CIPROFLOXACIN, FUROZOLIDONE and RIFABUTIN)
What is a varices
A dilated vein which is at risk of rupture resulting in haemorrhage and in the GI system can result in GI bleeding
What veins form the Hepatic portal vein
Superior mesenteric and splenic veins
Role of the hepatic portal vein
Carries nutrient rich blood from GI tract, gallbladder, pancreas and spleen to the liver
What vein returns blood from the liver to the heart
Inferior vena cava
Pressure in the hepatic portal vein
5-8 mmHg
What is pre-hepatic portal hypertension
Blockage of the hepatic portal vein BEFORE the liver