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Flashcards in LFTs Deck (30):
1

what are your normal lfts

ASt/ALT, ALP an d GGT
prothrombin, albumin and bilirubin

2

what is mre sensitive AST ot ALT

alt

3

where is ALT produced

mainly in the liver

4

where is AST produced

across the body

5

what is a common reason for AST/ALT to become raised

if there is injury to your hepatic cells then they will be forced out into the blood stream and therefore cause a rise - hepatic injury rather than linked to bilary tree

6

are ast/alt normally raised with stones

not normally but possible initially

7

when would your ALP be raised

in choleostatic conditions like gall stones

8

what can cause ALP rise

choleostatic conditions, bone injury, kidney injury, placenta

9

how long will it take for ALP to rise

can take up to a week and so is slow rising

10

what is bilirubin

it is a breakdown product of heam

11

what is the pathway of bilirubin

it will be broken down from heam and then travel with albumin to the liver where it will become conjugated and then it will be excreted through the fecaes or kidney

12

what happens to the urine and feaces in obstructive jaundice

the urine will become darker and the feaces will become pale because the bilirubin is not getting to the urine and the feaces to effect its colour

13

what clotting factors does the liver make

fibrinogen
prothrombin
factors 2,7,9,10

14

what does prothrombin time measure

it will measure the time it takes to converst prothrombin to thrombin

15

why is prothrombin time important in LFTS

because it reflects the livers ability to make plasma proteins (clotting factors in this case) and if this is upset then it is likely that there is damage to the liver of some sort

16

what are some causes of elevated prothrombin time other than liver disease

a congenital coagulopathy
warfarin
vitamin K malabsorption as it is required for the synthesis of your clotting factors

17

as well as clotting factors what does the liver make in relation to the blood clotting

anticoagulants such as proteins C and S and antithrombin 3

18

What is important to ask about in a history of someone with abnormal LFTs

drugs
travel
tattooes
sexual activity
associated symptoms like jaundice, tch arthralgia, weight loss
alcohol exposure and occupation are also important

19

what will a liver itch be worse

at night

20

when will the tiredness associated with liver disease be worse

in the morning

21

what medications are high risk for causing abnormal LFTs

paracetamol
Fluclox
statins
NSAIds
anti TB meds

22

what does a raised AST/ALT and a relatively normal ALP with normal or increased bilirubin

hepatocellular injury

23

what does a raised ALP with a normal AST/ALT ratio and raised bilirubin show

cholestasis

24

what does a raised prothrombin time (INR) show

this means that there is not enoufh clotting factors being made in the liver and so it may suggest hepatocellular dysfunction or vit K malabsorption

25

if somedody has an acute hepatocellular injury what will change in their LFTs ALT/AST ratio ir GGT and ALP

ast/alt

26

what test should you do if you suspect a acute hepatocellular picture

LFT
test for antigens for heps
test for CMV
carry out an ultrasound to asses the liver and its vasculature
ask about any hypotensive epidodes as the damage could be due to ischemia
review any meds

27

what do you need to rule out in acute liver presentation and how

coeliac (anti TTG test and biopsy)
Muscle disorders (as they can effect AST and so check the CK as that will tell you if ther has been muscle damage)
throid disorders

28

what would be your rarer causes of the acute hepatocellular presentation and how would you rule them out

autoimmune hepatitis ( test for smooth muscle antigen)
wilsons disease (test for ceruplasmin)
heamachromatosis (test for ferrin conc)
think about alpha 1 antitrypsin deficiency

29

what are some causes of hyperalbuminae that is unconjugated

a disease like haemolytic anemia that will break down excess heam in the body
right sided heart failure (as it will increase the pressure in the liver so the bilirubin will not be able to enter it properly or will be forced out)
rifampicin will impair take up of bilirubin
hyperthyroidism or advanved liver disease

30

what are your causes of conjugated hyperbilirubinemia

basically things that will effect the bilary tree:
gall stones, PSC, cholangiocarcinoma, pancreatitus, cirrhosis of the liver, rifampicin, acute hepatitis, hypoperfusion, TPN