peptic ulcer disease and gastric carcinoma Flashcards
how is an ulcer different to an erosion
- penetrates the muscularis mucosae
- can be acute or chronic (fibrosis)
prevalence of gastric-duodenal ulcers and m:f ratio, blood group
10% population
M:F 5:1
blood group A+
what is more common gastric or duodenal ulcers
duodenal ulcers
pathophysiology of peptic ulcer disease
produced by imbalance of gastro-mucosal defence mechanisms vs secretions and hormone gastrin
causes of peptic ulcer disease and why
- NSAIDs deplete mucosal defence
- stress: burn, sepsis
- smoking: damage and delay healing
- H.pylori
- acid pepsin vs mucosal resistance
- zollinger ellison syndrome get excess gastrin
prevalence of H.pylori in gastric vs duodenal ulcers
gastric=70%
duodenal=90%
what type of bacteria is H.pylori
spiral shaped gram negative acidophilic bacterium with flagella
where is h.pylori prevalence highest
africa and south america
more on socio-economic status
mechanism by which H.pylori isnt destroyed
- oral transmission
- produces urease to break down urea to bicarbonate and ammonia which buffers the acid
- adhesions help it to attach onto epithelial cells
where does h.pylori prefer in the body and why
lives in stomach next to epithelium in the antrum where it is protected by stomach mucosa
4 cytotoxins it produces h.pylori
- vacuolating cytotoxin (vacA) induction apoptosis, disrupt epithelial junction & block t cell response
- cytotoxin assoc. genes (cagA) alteration of signalling pathway and alter tight junctions
- phospholipases
- LPS induce inflammatory response
4 mechanisms of injury in H.pylori
-HYPERGASTRINEMIA
negative feedback for gastrin is blocked
-Antral somatostatin is depleted and increased gastrin release
- HYPERACIDITIY occurs with mucosal damage
- DIRECT MUCOSAL INJURY; cytotoxins
- INFLAMMATORY RESPONSE- mediated by macrophages, neutrophil & T cell
dx of H.pylori 4
- breath test: H.pylori produces from urea: ammonium and bicarbonate
- antibody measurement
- stool HP antigen test
- urease CLO test: take a biopsy from mucosa and place urea on it and see if it goes yellow to red
Prognosis of untreated H.Pylori infection
1.chronic active gastritis: predominantly antrum
(increased risk of duodenal ulcers)
2.chronic active pangastritis with some atrophy ( increased risk of gastric ulcers)
3.Chronic atrophic pangastritis (cancer risk)
4.metaplasia of duodenum
5.MALT gastric marginal B cell lymphoma
6. NSAID induced gastropathy
How do NSAIDS cause mucosal damage
affect COX1 also which is the housekeeping protective prostaglandins that protect mucosa
- increase mucosal blood flow
- stimulate bicarb and mucus secretion
Risk factors for NSAID induced ulcers 8
- age >60 years (atrophic gastritis)
- phx of PUD
- phx of adverse event with NSAID
- concomitant steroid use
- high dose NSAID or multiple
- hereditary predisp
- o blood group
- smoking
typical symptoms NSAID peptic ulcer disease
-epigastric pain (relief by food)
-nausea
-fullness
-bloating
-hunger pain
-night pain
ALARM S
alarm symptoms of NSAID peptic ulcer disease
anaemia haematemesis mealena vomiting anorexia pain radiation
treatment of benign peptic ulcer disease
- stop smoking
- avoid aspirin and nsaid
- PPI or H2 blockers
h.pylori eradication therapy
omeprazole 20mg
amoxicillin 1gram
clarithromycin 500mg
all three one week
omeprazole
clarithromycin 500mg
metronidazole 400mg
if fails can use Tripotassium Dicitratobismuthate 120mg or tetracycline
H.pylori eradication side effects
diarrhoea can get c.diff colitis metronidazole= metallic taste, flush, vomit headaches rash
management for NSAID induced ulcers
- stop NSAID or use lower dose
- co give with PPI
- use COX2 specifc eg celecoxib
5types of gastric carcinomas
- gastric adenocarcinoma
- gastric lymphoma
- GISTs (mostly benign leiomyomas)
- carcinoid tumours
- gastrinomas
factors assoc. with gastric carcinoma
some animals have fun playing all day games
smoking alcohol HP FAP syndromes pernicious anaemia Blood group A Diet rich in nitrosamines or salty and spicy gastric adenomatous polyps
what is Zollinger Ellison syndrome and where
- develop gastrinomas in pancreas and duodenum
- excess gastrin
- acts on parietal cells to increase acid secretion
which part of the multiple endocrine neoplasia is Zollinger ellsion part of
MEN1 but also alone
with parathyroid and pituitary
symptoms of Zollinger ellison
- multiple ulcers
- gi bleeds
- diarrhoea and steatorrhea as inactivated pancreatic enzymes and bile salts
management of ZE 4
surgical resection tumour
PPI
Octreotide injections to reduce gastrin levels
5 year survival for ze
60-75%
signs of perforation from peptic ulcer
peritonitis shock sudden sever pain air under diaphragm on x-ray shoulder tip pain
management of gastric outlet obstruction
- NG tube for vomit
- iv fluids
- acidosis correction
4 types of surgical management or peptic ulcers
- vagotomy
- pyloroplasty
- bilroth1
- bilroth2
what is vagotomy
cut vagus nerve to reduce gastrin secretion
what is pyloroplasty
cut the pylorus if the pyloric sphincter has thickened to relieve gastric outlet obstruction
what is bilroth 1
removal of pylorus to create a duodenal anastamosis
what is bilroth2
removal of the pylorus to create a jejunm anastomosis
where are gist tumours found
in the tissue in the interstitial cells of cajal
treatment for gist and how it works
imatinib bonds to c-kit a tyrosine kinase to prevent signalling
sign of gist on biopsy
spindle cell pattern
what does signet cell ring carcinoma produce
mucin
what is lintis plastica
leather bottle stomach
cancer gastric
fibrotic and rigid stomach that wont distend
see signet cell ring proliferation
where are gastric carcinomas most common 4
ccjf
china
japan
finland
colombia
most common gastric carcinoma
adenocarcinoma of mucus secreting cells
chemotherapy for gastric carcinom
5-fluorouracil
what are carcinoid tumous of the stomach assoc. to and where are they found
assoc. to chronic pernicious anaemia
seen in fundus
2 causes of gastric lymphomas
extranodal non Hodgkin lymphoma or
primary
what infection is closely assoc. to lymphoma gastric
h.pylori
what does malt stand for
mucosal assoc. lymphoid assoc. tumour most commonly seen in stomach
treatment of gastric lymphoma
- h.pylori eradication
- chemo
- rituximab
- resection
surgery options for gastric carcinoma
- Those proximal ie 5-10cm from og junction treat with sub total gastrectomy
- Total gastrectomy if tumour is >5cm from og junction
- Oseophagastrectomy tumours for type 2
- Lymphadenectomy should be performed
- Chemotherapy
3 types of gastro-oesophageal carcinoma classifiction
1=oesophageal
2=carcinoma of the cardia
3=sub cardial cancers that spread across junction
summary of gastric carcinoma treatment
total gastrectomy and lymphadenectomy
most common place for gastric adenocarcinoma
antrum 50%
2 types of gastric adenocarcinomas
intestinal= from areas with intestinal metaplasia
diffuse=normal gastric mucosa-lintis plastica
what do gastric adenocarcinomas arise from
mucus secreting cells
