Gastroenterology Flashcards
What serology is present in acute Hep B infection?
HbsAg (hep B surface antigen)
What does anti HBs?
Implies immunity to hep B either by infection or vaccination - it is negative in chronic disease
What does anti-HBc imply
previous (or current) infection. IgM anti-HBc appears during acute or recent hepatitis B infection and is present for about 6 months. IgG anti-HBc persists
what does amylase do
breaks down starch to sugars
what does maltase do
cleaves disaccharide maltose to glucose + glucose
what does sucrase do
cleaves sucrose to fructose and glucose
what does lactase do
cleaves disaccharide lactose to glucose + galactose
what is the inheritance of haemochromatosis
autosomal recessive
what antibiotics is most strongly associate with c diff
cephalosporins
what is the second line treatment of hepatic encephalopathy
rifaximin
what drug can help prevent recurrent c.diff
Bezlotoxumab
what drugs can cause a hepatocellular picture
paracetamol sodium valproate, phenytoin MAOIs halothane anti-tuberculosis: isoniazid, rifampicin, pyrazinamide statins alcohol amiodarone methyldopa nitrofurantoin
what drugs cause a cholestatic picture
combined oral contraceptive pill
antibiotics: flucloxacillin, co-amoxiclav, erythromycin*
anabolic steroids, testosterones
phenothiazines: chlorpromazine, prochlorperazine
sulphonylureas
fibrates
rare reported causes: nifedipine
name medications that cause cirrhosis
methotrexate
methyldopa
amiodarone
what HLA is associated with coeliac disease
HLA DQ2
what supplementation will likely be required following gastric bypass surgery
iron - as most surpass the duodenum where iron is absordbed
when is prophylaxis for SBP given
if ascited with protein level less than 15
choice is cipro
what is a rare complication of pancreatitis causing cotton wool spots on fundoscopy
ischaemic (Purtscher) retinopathy
what causes carcinoid synrome
release of serotinin
usually once carcinoid tumours have metastasised to liver
how can u treat carcinoid syndrome
ocreatide
what is used to treat SBBOS
rifaximin is now the treatment of choice due to relatively low resistance. Co-amoxiclav or metronidazole are also effective in the majority of patients.
what is whipple’s disease
rare multi-system disorder caused by Tropheryma whippelii infection. It is more common in those who are HLA-B27 positive and in middle-aged men.
jejunal biopsy shows deposition of macrophages containing Periodic acid-Schiff (PAS) granules is diagnostic of
whipples disease
how is whipples disease treated
co-trimox
how does teripressen work
causes contriction of the splanchnic vessels
older person, diarrhea, lots of mucus, hypokalaemia
villous adenoma
where is most likely affected in ischaemic colitis
splenic flexure
what rheumatological disease is most commonly associated with primary bilary cirrhosis
sjrogens
what is the triad of budd chairi
abdo pain
ascites
hepatomegaly
give causes of budd chiari
polycythaemia rubra vera
thrombophilia: activated protein C resistance, antithrombin III deficiency, protein C & S deficiencies
pregnancy
oral contraceptive pil
describe the difference between type 1 and type 2 hepatorenal syndrome
type 1 -fast onset
type 2 - slower onset (slightly better prognosis)
what scoring system can be uses to estimate the likelihood of someone having appendictis
alvarado
what primary prevention is given for oesophageal varices
propranolol: reduced rebleeding and mortality compared to placebo
endoscopic variceal band ligation (EVL)
what is the risk of endosopic variceal band ligation
ulcers - PPI given to prevent
what is dubin johnson syndrome
benign autosomal recessive disorder resulting in hyperbilirubinaemia (conjugated, therefore present in urine). It is due to a defect in the canillicular multispecific organic anion transporter (cMOAT) protein. This causes defective hepatic bilirubin excretion
what heart problem is angiodysplasia assoiciate with
aortic stenosis
what are the chances of having bowel cancer from a positive FOB test
5-15 percent
about 40 percent chance of having an adenoma
what gene mutations are most common in HNPCC
MSH2 (60 percent)
MLH1
they are DNA mismatch repair genes
what other cancer is most commonly associated with HNPCC
endometrial cancer
how is vertical tranmission of hep B in pregncnay prevented
give newborn hep B vaccine AND immunoglobulin
what is the mode of inheritance of peutz jehgers
autosomal dominant
what blood group is associated with gastric cancer
A
what needs to be checked before commencing azathioprine
TPMT activity
if deficient cannot metalobise azathioprine well and more prone to side effects
what can be used for resitant c diff
fidaxomicin
what are cardiac complications of carcidnoid
tricuspid insufficiency and pulmonary stenosis.
what is zollinger ellson syndrome
is condition characterised by excessive levels of gastrin, usually from a gastrin secreting tumour usually of the duodenum or pancreas. Around 30% occur as part of MEN type I syndrome
what is the diagnostic test for zollinger ellson syndrome
gastrin levels (fasting)
what is associated with gastric cancer on a pathology vlevel
signet ring cells
what blood test can be used to assess for chronic pancreatitis
faecal elastase
what conditions are associate with primary sclerosisng chonlangitis
UC
HIV
(also crohns)
what is the diagnostic investigation for PSC
ERCP
what cancers are you at increased risk from in PSC
cholangiocarcinoma (10 percent)
colon cancer
at what BMI can u be referred for bariatric surgery
no risk factors (>40) rish factors (>35)
what antibody is associated with primary biliary cholangitis
antimitochondrial
what is the gold standard investigation for GORD
24 hour oesophageal pH monitoring
what can be seen on imaging in pancreatic cancer
‘double duct’ sign - dilation of both the pancreatic and CBD
what biochemical marker is used to monitor efficacy of treatment in haemochromatosis
ferritin and transferin saturation
what investigation can confirm a diagnosis of gilberts syndrome
investigation: rise in bilirubin following prolonged fasting or IV nicotinic acid
for oesophageal/gastric cancer - what is the best method to assess for mural invasiion
endoscopic ultrasound
what is the carrier rate of CF
1 in 25
what clotting factor is paradoxically raised in liver failure
factor 8
what is the investigation of choice for bile acid malabsoption
the test of choice is SeHCAT
nuclear medicine test using a gamma-emitting selenium molecule in selenium homocholic acid taurine or tauroselcholic acid (SeHCAT)
scans are done 7 days apart to assess the retention/loss of radiolabelled 75SeHCAT
where do VIPomas usually originate
pancreas
which type of colonic polyps are more strongly associate with malignancy
flat or ‘sessile’ polyps
what medical therapy can help prevent cancer in lynch syndrome
apirin 600mg
