GI Investigations 1 Flashcards
List 4 GI Blood tests
LFTs are very useful to differentiate between _________ and _________
hepatitis, cholestasis (sluggish bile flow)
What is ALT and when would it be risen
List 2 specific causes
Alanine transaminase - rise when hepatocytes are damaged
eg. viral, alcoholic, drug- induced
What is AST and when would it be risen
Aspartate aminotransferase - slightly less specific than ALT as it is also produced in muscle and heart cells
Risen in alcohol-related liver disease
What is ALP and when would it be risen?
Where is ALP produced?
Alkaline phosphatase - rises in diseases of bile ducts
Produced in bile ducts, intestine, kidneys, placenta and bones
How does a rise in Bilirubin present?
Jaundice
What is GGT
List 2 examples of when this would be risen
Gamma Glutamyl Transpeptidase
Elevated in bile duct pathology, drugs, alcohol
Compare what changes in LFTs would be seen in a hepatocellular vs cholestatic/obstructive picture?
↑ ALT, AST - hepatocellular
↑ ALP, GGT - cholestatic/obstructive
List 3 causes for a decreased Albumin
- Liver damage
- Sepsis
- Kidney disease
List 2 causes of increased Globulin
- Autoimmune diseases
- Cirrhosis
Why is a fall in platelet count seen in liver cirrhosis?
Hypersplenism
Cirrhosis → portal hypertension → backflow into spleen
What disease is a/w low ceruloplasmin?
Wilsons disease
List 4 instances where you may require a stool test
- Indigestion
- Constipation and/or diarrhoea
- IBS or IBD
- Malabsorption
- Infection
What information can stool samples provide us?
List 3 examples of what some of these may indicated
Changes in colour, consistency, pH, presence of mucus, blood, WBC, bile, fat, sugars
- Increased fat seen in coeliac disease and pancreatitis
- High pH could indicate inflammation or cancer
- Enzyme immunoassays for C diff, H. pylori
What is the FIT test
Who is it offered too?
Fecal immunochemical test - Bowel Cancer screening - 60-74
Stool sample to check for faecal occult blood, if positive reffered for sigmoidoscopy or colonscopy
What is faecal calprotectin a very important marker of?
Why can we not soley rely on this marker for diagnosis?
IBD (Crohns, UC)
May give false positives, can be raised in:
- Infection eg salmonella, C.diff, diverticulitis
- Drugs NSAID, PPIs
What stool test may allow us to differentiate between IBD and IBS?
Positive faecal calprotectin > 250-300 (normal 50) indicates IBD
How can we identify infective causes of diarrhoea?
List 4 causes
Stool Cultures
List 2 consequences of an H.Pylori infection
- Ulcers
- Malignancies
List 3 tests to Identify H-Pylori
1. Urea Breath Test using radiolabelled carbon 13 or 14
2. Stool antigen test
3. Rapid Urease test (CLO) during endoscopy
Also IgG titer (serology) or Invasive Gastric mucosal biopsy
Explain the Urea Breath Test for H.Pylori
Rapid diagnostic procedure
- H.Pylori produces enzyme urease (urea → ammonia + CO2)
- Tablet/liquid containing urea is swallowed
- Amount of exhaled CO2 is measured
- Indicates presence of H. pylori in the stomach
Explain the CLO test for H.Pylori
CLO - Campylobacter-like organism
- During endoscopy, biopsy of stomach mucosa is taken
- Urea is added to this sample
- If H. pylori is present, urease enzyme will convert urea to ammonia
- Ammonia makes solution alkali → + result when pH is tested
Tripple Eradication therapy for treatment of H.Pylori?
PPI (e.g. omeprazole) plus 2 antibiotics (e.g. amoxicillin and clarithromycin) for 7 days
What does the imagine below show?
Air under diaphragm on right where liver should be - may indicate perforated viscus (on image air on left is a gastric bubble)
What are the 3 types of IBS?
IBSc - constipation
IBSd - diarrhoea
IBSm - mixed
