Flashcards in LFTs Deck (49)
Loading flashcards...
1
What is bilirubin formed from?
Breakdown of RBC porphyrin ring
2
What organ does insoluble unconjugated iron travel to?
Liver
3
How does insoluble unconjugated iron travel to the liver?
Bound to albumin
4
What happen to insoluble unconjugated bilirubin at the liver?
Liver enzymes conjugated it to form bilirubin glucuronide (conjugated bilirubin)
5
How is conjugated bilirubin excreted?
In bile = soluble
6
How can conjugated bilirubin be excreted directly?
In urine
7
What happens to conjugated bilirubin in bile?
It is broken down in the gut into urobilinogen (some reabsorbed and excreted by the kidney) and stercobilinogen (forms brown colour of stool)
8
What sign can increase bilirubin cause?
Jaundice
9
At what level of bilirubin would jaundice be visible?
>35 micro mol/L
10
What are the 4 liver enzymes?
Alanine transaminase (ALT)
Aspartase transaminase (AST)
Alkaline phosphate (ALP)
Gama glutanyl transferase (GGT)
11
What are the 3 intracellular liver enzymes?
ALT
AST
ALP
12
What happens to ALT when liver cells damaged?
Release from liver into blood stream
13
Is ALT specific?
Yes, found almost exclusively in the liver
14
Is AST specific?
Not as much as ALT - also found in cardiac tissue and muscle
15
What happens to AST when liver cells damaged?
Released from liver into blood stream
16
Where is ALP found?
Mainly in liver and bone
17
What is the function of ALP?
Involved in transport of substances across the cell membrane
18
Why might ALP be raised?
Physiologically - metabolically active cells e.g. bones growing, pregnant
Bile drainage obstructed
19
Where is ALP found in the liver?
In cells near the bile ducts sad canaliculae
20
Where is GGT found in the liver?
In hepatocytes and biliary epithelial cells
21
What is the purpose of GGT?
Plays a role in the metabolism of drugs
22
Name 2 conditions which cause a rise in GGT?
Alcohol and certain drugs
Bile duct obsturction
23
Where is albumin synthesised?
Liver
24
What happens to albumin levels as liver function deteriorates?
Falls
25
Apart from liver function, name 3 other causes of low albumin levels?
Protienuria
Poor nutrition
Hormonal imbalances
26
What happens to prothrombin time if liver problem?
Increases
27
What causes pre-hepatic jaundice?
Increased breakdown of RBCs
28
What causes intra-hepatic jaundice?
Problem in the liver
29
What causes post-hepatic jaundice?
Bile duct system damaged/ obstructed = unable to move bile into digestive tract
30
Bilirubin in prehepatic jaundice?
Raised
31
AST/ ALT in prehepatic jaundice?
Normal
32
ALP in prehepatic jaundice?
Normal
33
Haemoglobin in prehepatic jaundice?
Reduced
34
Jaundice in prehepatic jaundice?
Usually mild
35
Urine in prehepatic jaundice?
Not dark
36
Bilirubin in intrahepatic jaundice?
Raised
37
AST/ ALT in intrahepatic jaundice?
Raised
38
ALP in intrahepatic jaudnice?
Slightly raised
39
Hb in intrahepatic jaundice?
Normal
40
Jaundice in intrahepatic jaudnice?
May be marked
41
Other name for post hepatic jaundice?
Cholestatic
42
Bilirubin in posthepatic jaundice?
Raised
43
AST/ ALT in posthepatic jaundice?
slightly raised
44
ALP in posthepatic jaundice?
very raised
45
Hb in posthepatic jaudnice?
Normal
46
Jaundice in posthepatic jaundice?
May be marked
47
Stool in posthepatic jaudnice?
Pale
48
What effect on stool does bilirubin have?
Make it darker -> pale stool = lack of bilirubin in GI tract
49
