Gastroenterology 3 Flashcards
Fidamoxicin mechanism of action?
Bactericidal ! - inhibit RNA polymerase
What organism species is a major protective constituent of faecal flora?
Bacteroides spp.
Most common presentation of IgG4 disease?
sclerosing cholangitis
Commonest adenoma and adenoma likely to cause malignancy?
Commonest adenoma = Tubular
Adenoma causing cancer = Villous
What malignancy is associated with coeliac disease?
Lymphoproliferative malignancy
GI cancer
Eosinophilic esophagitis treatment?
PPI for 8 weeks
Then liquid budesonide if not responsive to PPI
Types of laxatives - Eg. and mechanism of action
Osmotic
Stimulant
Pro-secretory
5HT4 agonist
bile acid transporter inhibitors
Osmotic - Lactulose/ Polyethylene ( more superior)
Stimulant- Bisacodyl, glycerin = propagate colonic contractions
Pro-secretory -stimulate efflux of water/ions into intestinal lumen - helps with defecation
5HT4 - Fast excitatory potentials - induce mucosal secretion
Elobixibant - induce bile acid malabsorption in terminal ileum - retrograde flow in colon = mix with microbiota producing bile acids that induce colonic secretion
Role of Faecal Calprotectin?
Diagnostic screening + relapse predictor + assess mucosal healing
(Inflammation specific, not disease specific)
Hereditary diffuse gastric cancer + Lobular breast cancer - what mutation?
CDH1 = E-cadherin
Gilbert syndrome mutation?
UDPG
UAT1A1
H.pylori failed treatment - then what?
Levofloxacin based triple therapy ( Levofloxacin, PPI, Amoxicillin)
OR Quadruple triple ( Metronidazole, bismuth, PPI, Tetracycline)
Severe Hep E - treatment?
Ribavarin
Hereditary hemochromatosis - specific test and clue?
Transferrin saturation > 55%
Hepcidin deficiency
Lactose malabsorption - how to test for it?
Lactose intolerance test
- oral lactose and check BGL : +ve if symptoms after oral lactose and BGL didn’t rise > 1 mmol
Hydrogen breath test ( sensitive and specific)
- Rise in breath hydrogen after lactose ingestion
Small bowel biopsy ( gold standard)
-differentiate primary and secondary Lactose malabsorption
Genetic test
-LCT-13910 polymorphism
Cow milk allergy - how to differentiate IgE and non-IgE mediated?
IgE mediated - Symptoms start < 2 hours after drinking
Non-IgE - symptoms > 2 hours after drinking
Esophagus dysphagia symptoms?
Cause of it?
Chest pain + Regurgitation + Water brash
Cause - Brainstem CVA/ Parkinson’s disease
Oropharyngeal dysphagia symptoms?
Utility to invx it?
Aspiration pneumonia, choking while swallowing + weakness, voice disturbance
Video fluoroscopy - barium swallow
Main pathway for paracetamol metabolism?
smaller pathways for paracetamol metabolism?
Main pathways
UDP-glucuronosyltransferases (UAT1A1) and Sulfotransferases (SULT1A1)
- conjugate PCM into glucorinide and sulfate - excreted in urine
Small pathways
- NAPQI metabolism by Glutathione
- Renal excretion unchanged
What is key features of Ogilvie syndrome?
Painless abdominal distention - rapid = Large colon
Treatment
Fast + NGT - decompress
Endoscopic decompression is usually successful but colonic distention reoccurs
Rectal tube not useful esp. proximally
Blatchford score usage does what?
Rockall score usage does what?
Blatchford score Predicts who needs admission and therapy -unlikely need admission/treatment if; Urea < 6.5 Normal vital signs
Rockall score
Risk categorization before and after endoscopy
-hemodynamic instability + bleeding = scope within 12 hours
-hemodynamically stable = Scope within 24 hours
After endoscopy successful for UGIB - what is the next step?
Bolus IV PPI and keep on infusion for 72 hours
No need 2nd check of endoscopy unless clinically bleeding
ZES is associated with what genetic syndrome?
it secretes what hormone and it’s function?
How to test for ZES?
How to treat ZES?
MEN1
Gastrin
- increase Gastric motility and lower oesophageal sphincters
- Increase gastric acid and pepsinogen secretion
- increase gastric, duodenal, colonic mucosa growth to secrete more gastrin!
Give secretin stimulation test - if Gastrin rises > 200 = ZES
Tx - PPI and anti-histamine
