Gastro Flashcards
(139 cards)
What is the primary factor leading to accumulation of ascities in patients with cirrhosis?
Splanchnic dilatation
What is the pathophysiology of ascites in cirrhosis?
Cirrhosis -> portal hypertension (sinusoidal pressure > 12 mmHg)-> splanchnic dilatation-> increase splanchnic pressure -> formation of ascities
Splanchnic dilatation also results in arterial underfilling -> activation of vasoconstriction and antinatriuretic factors -> sodium retention -> plasma volume expansion -> ascites
what is the serum to ascites albumin gradient (SAAG)? What is it used to identify?
SAAG = serum albumin - ascites albumin
Used to identify the presence of portal hypertension
> 11 = portal HT (cirrhosis, HF, bud chiari, alcholic hepatitis)
what does the appearance of the following ascitic fluid suggest: clear yellow brown turbid milky pink or bloody
Clear yellow = normal bili and protein
brown = high bili
turbid = infection
milky = elevated triglyceride concentration usually secondary to lymphoma
Pink or bloody = traumatic tap, malignancy, cirrhosis, punctured vessel
What Ix do you order for an ascitic fluid?
MCS
Protein; if >=2.5 or 3 gldL then exudate, if 1.0 = malignancy
Amylase, lipase- elevated if due to pancreatitis or gut perforation
Tb- Tb PCR
Cytology - malignant cells
what is the treatment for ascites due to cirrhosis?
- Spironolactone50-100 mg PO OD, increase by 100 mg q 4 days up to 400 mg OD.
2, Can add Frusemide40 mg PO. Increase by 40 mg q 4 days up to 160 mg OD - Amiloride 10-20 mg OD if pt cannot tolerate spironolactone
what is the Tx fro severe and refractory ascites sue to liver cirrhosis?
- Transplant only definitive therapeutic option
2. TIPS to shunt between hepatic and portal veins
what does B12 deficiency lead to?
Pernicious anaemia identified by macrocytosis, intramedullary haemolysis and peripheral neuropathy
Where is our source of Vit B12?
Where is Vitamin B12 stored?
How is Vitamin B12 absorbed?
Meat and dairy is the only source of Vit B12
Total body stores are 2-5 mg with half of stores in the liver
Cobalamin is liberated from food by acid and pepsin. Binds to R-factors in the saliva and gastric juice.
In the duodenum, cobalmin freed from R-proteins due to actions of PANCREATIC proteases. Then binds to intrinsic factor.
The IF-Cbl complex binds to ileal receptors in the terminal ileum.
MOA Azathioprine?
Immunosuppressive drug.
A purine anti-metabolite.
Metabolised via mercaptopurine to thioguinine metabolites which interfere with purine synthesis imparing with lymphocyte proliferation, celluluar immunity and anti-body responses.
Indications for Azathioprine
Prevention of post transplant rejection
immune and inflammatory diseases
What is the significance of TMPT testing when starting azathioprine?
1 in 300 ppl have low or no TPMT activity and are at severe risk of myelosuppresion. Avoid use or reduce dose to 1/10.
What is the interaction of azathioprine and allopurinol?
Allopurinol reduces azathioprine metabolism increasing the risk of severe bone marrow toxicity
What results would you expect in a pt with azathioprine resistance?
high 6MMP, low 6-TGN
Describe the pathway of azathioprine metabolism
AZA -> 6-MP -> 6 - MMP via TPMT
AZA -> 6-MP -> 6-TIMP -> 6-TXMP -> 6- TGN
What is the recommended treatment for Hepatitis C Genotype 1?
Sofosbuvir (Nucleotide polymerase inhibitor) + ribavirin + PEG for 12 weeks or
Olysio for 12 weeks + ribavirin + PEG for 24 weeks
If not elgible to receive interferon:
Solvadi + Olysio +/- ribavirin for 12 weeks or
Solvadi + ribavirin for 24 weeks
How many Hep C genotypes are there?
6
What is the treatment for Hep C Genotype 2?
Solvadi + ribavirin for 12 weeks
What is the treatment for Hep C Genotype 3?
Solvadi + ribavirin for 24 weeks
What is the treatment for Hep C Genetoype 4?
Solvadi + ribavirin + PEG for 12 weeks or
Olysio fro 12 weeks + ribavirin + PEG for 24-28 weeks
If not eligible for interferon:
Solvadi + ribavirin for 24 weeks
what is the treatment for Hep C genotype 5 or 6?
Solvadi + ribavirin + PEG for 12 weeks or
Ribavirin + PEG for 48 weeks
If not eligible to receive Interferon there are no recommended treatment options
What are the American Gastro Association guidelines for a pt with Barrett’s oesophagus:
without dysplasia
low grade dysplasia
High-grade dysplasia in the absence of eradication therapy
No dysplasia : 3-5 years
Low grade: 6-12 months
High grade dysplasia in the absence of eradication therapy: 3 months
What is the treatment for recurrent C. diff infection?
Duodenal infusion of faeces.
Sig more effective than the use of vancomycin
What is the recommended guidelines for colorectal ca screening for average or slightly increased risk (Asymptomatic or one first or second degree relative with CRC diagnosed at 55 years or older)
FOBT every 2 years from age 50 years