Helicobacter Pylori and Gastric Disease Flashcards
what is dyspepsia?
pain or discomfort in the upper abdomen
what symptoms does dyspepsia include?
> upper abdominal discomfort > retrosternal pain > anorexia > nausea > vomiting > bloating > fullness > early satiety > heart burn
what are upper gi causes of dyspepsia?
> peptic ulcer
gastritis
non-ulcer dyspepsia
gastric cancer
what are lower causes of dyspepsia?
> IBS
> colonic cancer
how may the gall bladder cause dyspepsia?
formation of gallstones
what systemic problems may cause dyspepsia?
> cardiac
drugs
psychological
in dyspepsia when would you refer for an endoscopy?
Anorexia Loss in weight Anaemia Recent onset >55 years Melaena/haematemesis Mass Swallowing problems (dysphagia)
what are the risks associated with upper gi endoscopy?
> 1:2000 risk perforation
bleeding
drug reaction
what blood tests are carried out in dyspepsia?
> fbc > ferritin > lft's > u and e's > calcium > glucose > ceoliac serology/serum iga
what would you look for in a drug history in patients with dyspepsia?
> nsaids > steriods > biphosphonates > calcium antagonists > nitrates > throphyllines
if a patient who is over 55 prsents with dyspepsia what would you carry out?
an upper gi endoscopy
a patient who is less than 55 present with dyspepsia. what test would you carry out?
test for helicobacter pylori
if the helicobacter pylori test is positive what is your next step?
eradication therapy and symptomatic treatment with PPIs or H2R antagonists.
if symptoms resist refer them to GI
describe the helicobacter pylori bacterium
> gram negative
spiral shaped
microaerophilic
flagellated
how much of the world population is infected with helicobacter pylori?
50%
where does h. pylori colonise?
surface layer of gastric type mucosa. does not penetrate the epithelial layer.
what does h. pylori invoke in the underlying mucosa?
host immune response
what are the clinical outcomes of h. pylori?
> asymptomatic > chronic gastritis > chronic atrophic gastritis > intestinal metaplasia > gastric/duodenal ulcers > gastric cancer
what can the outcome of h. pylori depend on?
> site of colonisaton
characteristics of bacteria
host factors: genetics and enviroment
what are the effects of antral dominant gastritis?
> increase in acid
low risk of gastric ca
duodenal disease
what is the effect of a chronic h. pylori infection that leads to mild mixed gastritis?
this leads to normal acid production and no significant disease
what is the effect of corpus predominant gastritis from chronic h. pylori infection?
> decrease in acid
gastric atrophy
leading to gastric ca
how would you non-invasively diagnose h. pylori infection?
> serology: IgG
urea breath test
stool antigen test (need to be off ppi for 2 weeks)
how may you invasivley diagnose h. pylori infection?
through and endoscopy.
> histology of gastric biopsies
> culture of gastric biopsies
> rapid slide urease test
what carbon atoms are used in urease dependent diagnosis?
c13 and c14
what is measured in breath tests to indicate h. pylori positive?
c13 or c14 labelled co2
what is utilised in slide urease tests for h. pylori diagnosis?
> ammonia
define gastritis
inflammation of gastric mucosa
what are the causes of gastritis?
> autoimmune (parietal cells)
bacterial (H. pylori)
chemical (NSAIDs/bile)
what are the majority of peptic ulcers caused by?
h. pylori infection
what can cause peptic ulcers?
> h. pylori infection
NSAIDs
smoking
what are some rare causes of peptic ulcers?
> zollinger-ellison syndrome
hyperparathyroidism
crohn’s disease
name some symptoms associated with peptic ulcers
> epigastric pain > nocturnal pain > back pain > nausea (vomiting) > weight loss > epigastric tenderness > bleeding: haematemesis, melaena, anaemia
how would you treat an ulcer caused by h. pylori?
eradication therapy
how may you treat a peptic ulcer?
> proton pump inhibitors
h2 antagonists
stopping nsaids if possible (or continued to recieve other protective agents following eradication therapy)
describe eradication of h. pylori infection
triple therapy for 7 days:
> clarithromycin 500mg bd
> amoxicillin 1g bd
> PPI (omeprazole) 20mg bd
what are the main reason eradication of h. pylori fails?
> resistance to antibiotics
> poor compliance
what are the complications of a peptic ulcer?
> acute bleeding > chronic bleeding > perforation > fibrotic stricture > gastric outlet obstruction
describe the vomit in gastric outlet obstruction
> lacks bile
> fermented food stuffs
what are the symptoms id gastric outlet obstruction?
> early satiety > abdominal distension > weight loss > gastric splash > dehydration
why is dehydration an effect of gastric outlet obstruction?
there is loss of h+ ions and cl- ions in the vomit
what changes would be seen in bloods in gastric outlet obstruction?
> low cl
low na
low k
renal impairment
how would you diagnose gastric outlet obstruction?
UGIE: prolonged fast then aspiration of gastric contents. identifies cause
how may gastric cancer patients present?
> dyspepsia > early satiety > nausea > weight loss > gi bleeding > iron deficiency > anaemia > gastric outlet obstruction
why would you carry out endoscopy’s and biopsies in a patient with gastric cancer?
to make a histological diagnosis
what staging investigations might you carry out with gastric cancer?
> ct chest/abdomen
who would be present in an MDT discussion about a patient with gastric cancer?
> gastroenterologist > pathologist > radiologist > upper gi surgeons > oncologists > specialist nurses
