Gastroenterology Flashcards
Abx for spontaneous bacterial peritonitis
Cefotaxime
SBP is complication of …
Causative organisms are …
Ascites secondary to cirrhosis (normally alcoholic)
E coli, Klebsiella, S pneumoniae, Enterococci
Salmonella ABx
Ciprofloxacin
Define chronic diarrhoea
3+ stools/day for >4 weeks
Shigella ABx
Ampicillin or ciprofloxacin
Campylobacter ABx
Erythromycin
C diff Rx
Metronidazole, vancomycin
Yersinia ABx
Tetracycline
RFs for Small Bowel overgrowth (where CRP NORMAL)
Bowel surgery
Crohn’s
Motility disorders e.g. Scleroderma
% mortality in severe acute pancreatitis
20%
Ix for gastrinoma
Gastrin >1000
Then do secretin test (rise >200 = gastrinoma)
Then do pancreatic imaging
Abdominal bloating, intermittent diarrhoea, strong farts
Giardiasis
Whipples disease: demographic, causative organism
Middle aged male
Tropheryma whippelii
Often affects small bowel -> malabsorption
Fatigue, weight loss, fever, arthralgia, diarrhoea, middle aged male
Whipple’s disease
Whipples disease SB histology
Abnormal macrophages stain magenta with PAS
What is transferrin
glycoprotein produced in the liver
transports iron to cells
regulated by body iron stores
Transferrin levels in Fe deficiency and iron overload
transferrin production increases in Fe deficiency
iron overload decreases.
What is ferritin?
Levels of ferritin in Fe deficiency and Fe overload
present in all cells, iron storage
reduced in states of iron deficiency
raised in states of iron overload.
MOA hereditary haemochromatosis
increased iron absorption in the duodenum and proximal small intestine
Inheritance hereditary haemochromatosis and gene mutation
AR
C282Y HFE mutation
Organs affected in hereditary haemochromatosis
cirrhosis, restrictive cardiomyopathy, diabetes mellitus, arthropathy, skin hyperpigmentation, and gonadal failure.
Ix hereditary haemochromatosis
transferrin saturation >45% = initial screening test
then genetic screening (C282Y HFE mutation)
NB if ferritin >1000 do liver biopsy
% Down’s with ASD
40%
GI manifestations in Down’s
Duodenal atresia - DOUBLE BUBBLE sign
Hirschprung’s disease
Perioral dermatitis + acral (hand and foot) erythema. Which deficiency post bowel resection?
Zinc deficiency
What is Mackler’s triad? Indicates?
vomiting, chest pain and surgical emphysema
oesophageal rupture
but absent in almost half the cases
Ix for oesophageal rupture
gastrograffin swallow
Melanosis coli due to
Chronic laxative abuse (containing anthraquinones)
LFTs for alcoholic hepatitis
AST >ALT 2:1
UC associated with which liver pathologies
PSC
Cholangiocarcinoma
Lethargy + itching + BG UC
PSC
Ix for PSC
ERCP/ MRCP
multiple intrahepatic and extrahepatic bile duct strictures and dilatations
Refeeding syndrome comprises:
Low K, Phos, Mg
Deficiencies in vitamins, for example, thiamine
Fluid overload with oedema
Ix after excision colon adenocarcinoma
colonoscopy annually for at least two years
Carcinoid syndrome Sx
Flushing and diarrhoea
Release serotonin and other vasoactive peptides
Neuroendocrine tumour (gut, lungs)
Ix carcinoid syndrome
high urinary 5-hydroxyindoleacetic acid
Rx carcinoid syndrome
Rx = somatostatin analogue, surgical resection
Why use lactulose in cirrhosis/hepatic encephalopathy
Osmotic laxatives
Stops proliferation of ammonia-forming gut organisms
Increases protein clearance from gut
What is portal hypertensive gastropathy? Risks of it?
Vascular disorder
Complication of chronic liver disease
Causes UGI bleed in patients with cirrhosis + portal HTN
Rx UGI bleed
Somatostatin or terlipressin
If bleeding stops then start on BB
Consider shunt if rebleed despite BB
Genotype associated w/ lowest levels a1at
PiZZ
Return from tanzania, acute watery diarrhoea with some blood. Likely cause? Rx?
E coli travellers diarrhoea
Ciprofloxacin
Causes bloody/mucus stool
E coli, Shigella, Yersinia
Offensive smelling diarrhoea insidious onset (3 days - 3 weeks). Cause?
Giardia
Ix Giardia
Cysts in stool
Trophozoites in SB mucosal biopsy
Rx Giardia diarrhoea (insidious onset compared to E coli)
Metronidazole