GI track diseases I Flashcards
Disorders of the Oesophagus
obstruction
inflammation
What does obstruction of Oesophagus cause?
dysphagia
dysphagia
inability to swallow, feeling something is stuck
What is dysphagia caused by?
carcinoma - presents late, usually inoperable
benign structure (eg. scar tissue) - associated with reflux oesophagitis
stroke
neurological issues
- motor neurone disease
What does lower oesophageal sphincter protect against?
lower oesophageal sphincter (LES) protects against reflux of HCl
GORD/GERD - Gastro-oesopheal reflex disease
HCl moves into oesophagus
What is GORD/GERD caused by?
Central NS depressant, pregnancy, alcohol
Anatomical changes resulting from disorders of oesophagus
- infiltration of inflammatory cells in the squamous epithelial layer
- neutrophils are markers of severe injury
Treatment of inflammation of the oesophageal mucosa
removal of acid, sleeping upright, smaller meals (reduced stimulus for HCl)
What can we use to detect oesopahitis?
gastroscopy
Oesophageal Varices
secondary to liver disease
end up with portal hypertension
- blood can’t flow properly through hepatic portal vein
blood diverted to sub-musosal veins - gastric and oesophageal
small vessel abnormally dilated
very prone to bleeding - vomiting blood
Disorders of the stomach
gastritis
What is gastritis?
inflammation of the gastric mucosa to HCl
Acute gastritis
neutrophil infiltration
Chronic gastritis
long term changes in cell types, lymphocytes, intestinal metaplasia and atrophy
What does chronic gastritis lead to?
ulcer
- breach of 4-layer structure
- stomach contact leaks into peritoneum
Range of gastritis
loss of superficial mucosa
rupture of stomach
acute GI bleeding
What is gastritis associated with?
alcohol and tobacco
servere stress/chemo
bacterial and viral infections
NSAIDs eg. ibuprofen
What do NSAIDs do to the stomach?
impacts mucus and bicarbonate production
What does alcohol and tobacco do to stomach?
increases HCl production
damaging blood supply
What are the three ways damage is caused to the stomach?
increased HCl
decreased HCO3 - reduced blood flow
disruption to mucus layer
- direct damage to epithelium
Is gastritis self-limiting?
yes
- does not require more than simple OCT treatment
How to diagnose chronic infection with H.Pylori
biopsy
- presence of bacteria or urease enzyme activity OR urea breath test OR stool sample
Complications of disorders if the stomach
bleeding
perforation of stomach/duodemun
severe pain/rigid abdomen - will require surgery
Treatment of disorders of the stomach
Al/Mg hydroxide eg. gaviscon
Histamine H2 receptor antagonist - reduces HCl production
Proton pump inhibitors - switch off HCl production
Antibiotics - against H.pylori
Malabsorption Syndromes
Defective Intraluminal Digestion
Mucosal
Reduced SI surface area
Defective Intraluminal Digestion
Pancreatic insufficiency
- no enzyme or bicarbonate
- pancreatitis
- CF
Biliary Insufficiency
- no bile, no emulsification which leads to fat malabsorption
Bacterial Overgrowth in Small Intestine (SIBO) - colonic bacteria enter sl
Mucosal Malabsorption
Disaccharidase deficiency
- lactose intolerance
Abetolipoproteinaemia
- LCFA malabsorption
Primary bile acid malabsorption
- causes bile acid diarrhoea
Reduced SI surface area
coeliac disease
crohn disease
Fat malabsorption
greasy stool which do not flush
bile insufficiency
pancreatic lipase deficiency
mucosal defects
How to confirm fat malabsorption
faecal fat test
Coeliac disease
sensitivity to gluten from wheat and close related grains
t-cell mediated inflammatory reaction
anti-gliadin antibodies
dermatitis herpetiformis
fluid filled blisters
skin manifestation of celiac disease in 15-25%
SI biopsy to diagnose coeliac disease
- atrophy and loss of villi
- intra-epithelial lymphocytes - immune reaction
- crypts elongated
- overall mucosal thickness in unchanged
What happens to coeliac disease in gluten free diet?
musosal histology reverts to near normal following period of gluten exclusion
What are the 4 major causes of intestinal obstruction
herniation of segment
surgical adhesions
intussusceptions
volvulus
herniation of segment
weakness in a wall of peritoneal cavity causes blockage and loop of bowel loses blood supply
- surgery
Surgical adhesions
surgery or infection resulting in Peritonitis
(forming of scar tissue on outside)
as infection heals, fibrous bridges causing strangulations of intestinal segment, bowl blockage
intussusceptions
segment of intestine becomes telescoped within a distal segment during peristalsis
- defect of peristalsis
volvulus
complete twisting of loop of bowel, connective tissue to abnormal wall is lost
Is volvulus rare?
rare
birth defect
malrotation lacks normal attachment to abdominal wall
volvulus symptoms
vomiting
trapped gas
abdominal pain and distension
constipation
Superior mensenteric artery syndrome
- occurs in very learn people
- flattering of duodenum by SMA
- anorexia (very low visceral fat)
- duodenum crushed between arteries
