Feb22 M1,2-Hepatic Function Liver Disease

Question 1

true liver function tests

Answer 1

• total serum protein and albumin
• total bilirubin
• prothrombin time (PT, INR)

Question 2

fake LFTs

Answer 2

• ALT
• AST
• AP

Question 3

ALT charact

Answer 3

released when liver cells damaged

normal 5-40

Question 4

AST charact

Answer 4

can come from liver but also heart muscle intestine pancreas

normal 8-20

Question 5

AST:ALT ratio in alcoholics

Answer 5

2:1 AST:ALT

Question 6

AP charact

Answer 6

normal 20-70. found in liver (can frac or do isoenzymes to check if not from bone)
marker of OBSTRUCTION or infiltrative disease (cholestatic disease)

Question 7

how to check if AP shows cholestatic liver injury (bile not emptying properly)

Answer 7

GGT (gamma GT) must be elevated too

Question 8

(EXAM) bilirubin source and 2 types

Answer 8

indirect (unconjugated): from old RBCs.

conjugated (direct): after liver adds glucuronic acid to make it water soluble for excretion

Question 9

(EXAM) bilirubin excretion

Answer 9

stool (makes it brown)

urine (high bilirubin = black urine)

Question 10

(EXAM) normal total bilirubin

Answer 10

0.3-1.0 mg per dL

Question 11

(EXAM) direct bilirubin tells what

Answer 11

amount of bilirubin liver was able to manage

Question 12

(EXAM) how bilirubin made from heme

Answer 12

IN MACROPHAGES:

1. heme oxygenase transforms open alpha group on heme: makes biliverdin
2. biliverdin reduced by biliverdin reductase to make bilirubin

Question 13

(EXAM) what happens to bilirubin in hepatocytes

Answer 13

conjugated to form bilirubin diglucuronide (DIRECT) by UDP-glucuronyl transferase

Question 14

(EXAM) what happens to bilirubin diglucuronide in bacteria of the gut

Answer 14

transformed in urobilinogen (which is what goes to urine) and stercobilinogen (in the stool)

Question 15

3 types of jaundice (also called icterus)

Answer 15

(jaundice = serum bilirubin over 3 mg per dL)

prehaptic, intrahepatic, posthepatic

Question 16

prehepatic jaundice

Answer 16

hemolytic anemia, increased load of bilirubin

Question 17

intrahepatic jaundice

Answer 17

problem inside liver in making direct bilirubin (infection, chemical, drug, genetics, autoimmune, neonatal)

Question 18

posthepatic jaundice

Answer 18

intrahepatic bile ducts (drug, PBC, cholangitis)

extrahepatic bile ducts (gallstones, pancreatic tumor, cholangiocarcinoma)

Question 19

2 types of drug injuries to the liver

Answer 19

• predictable (tylenol): we know the quantity

- by chance

Question 20

elevated bilirubin and jaundice: which is up direct or indirect?

Answer 20

both. DIRECT is the most of it. (bc still transforming to direct, it’s a clearance problem)

Question 21

LFTs in liver problem

Answer 21

direct bilirubin up
indirect bilirubin up
albumin down
INR up

Question 22

steps in determining what kind of jaundice is present

Answer 22

1. check the conjugated bilirubin (is normal in pre, but is high in intra and post)
2. ask for color of stools (are light colored if extrahepatic)

Question 23

other way to distinguish posthepatic jaundice

Answer 23

high ALP (AP) and NO urine urobilinogen

Question 24

(IMPORTANT)extrahepatic causes of biliary obstruction + most common of these

Answer 24

• choledocholithiasis
• malignancy (cholangio, PANCREATIC IS MOST COMMON, GB, ampullary)
• PSC
• AIDS cholangiopathy

Question 25

(IMPORTANT) causes of intrahepatic biliary obstruction

Answer 25

- TPN (total parenteral nutrition) - sepsis - PSC - PBC - intrahepatic mass

Question 26

main things that kill the liver

Answer 26

1. fat 2. alcohol 3. autoimmune (PSC and PBC) 4. viruses 5. drugs ...

Question 27

how to dx the etiology of liver disease using the fake LFTs (liver enzyme tests)

Answer 27

- enzymes less 300 = alcohol, cirrhosis, obstruction (AST:ALT 2:1 for alcohol - enzymes 500-1000 = ACUTE biliary obstruction - enzymes over 1000 = ischemia, toxin, virus/

Question 28

6 causes of fulminant hepatic failure (mnemonic ABCDEF)

Answer 28

``` A: acetaminophen B: hepB C: hepC, cryptogenic D: hepD, drugs E: esoteric (Wilson's Budd-Chiari) F: fatty infiltration (acute fatty liver of pregnancy, Reye's) ```

Question 29

ddx of ascites + main one

Answer 29

-PORTAL HTN (85%) -malignancy -infection -renal -endocrine ...

Question 30

(EXAM) what to do to investigate ascites

Answer 30

measure serum-ascites albumin gradient (SAAG): more than 11 is high

Question 31

(EXAM) meaning of SAAG

Answer 31

- high SAAG = transudative process = LIVER CAUSE - low SAAG = exudative process = PERITONEUM CAUSE (peritoneal carcinomatosis, peritonitis, pancreatic ascites, bile leak, nephrotic syndrome,.._

Question 32

(imp?) when ascites associated with portal htn

Answer 32

when SAAG over 1.1

Question 33

(EXAM) main pathophgy of ascites (2)

Answer 33

1. Na retention secondary to splanchnic and systemic vasodilation (dereased arterial volume led to Na retaining mechanisms) 2. extrahepatic: CHF, constrictive pericarditis, Budd Chiari syndrome)

Question 34

(EXAM) portal htn def and value

Answer 34

portal system branches into sinusoids (and then these will drain in hepatic venous system). **portal htn = portal vein P over 11

Question 35

(EXAM) prehepatic causes of portal htn

Answer 35

- congenital atresia or stenosis (portal vein) - thrombosis of portal vein - splenic vein thrombosis - extrinsic compression (tumor)

Question 36

(EXAM) intrahepatic causes of portal htn

Answer 36

- cirrhosis (sinusoidal obstruction) - bilharzial periportal fibrosis - sinusoidal obstruction syndrome (chemo)

Question 37

(EXAM) posthepatic causes of portal htn

Answer 37

- Budd Chiari (hepatic vein thrombosis) - cardiac disease (valvular disease or constrictive pericarditis) - right heart failure

Question 38

(EXAM) cirrhosis pathophgy of ascites and other pathophgies

Answer 38

- increased intrahepatic resist due to fibrosis, regenerative nodules, hepatic venular vasoconstriction = sinusoidal htn - lymph leakage in sinusoids - TB - peritoneal lymph leakage - bile ascites - pancreatic ascites

Question 39

most important risk factor for liver disease + 2nd most important

Answer 39

alcohol | 2nd is obesity (fat)

Question 40

ALT of 70 (normal below 35) approach

Answer 40

means nothing. repeat the test

Question 41

AST 55 (normal <30), ALT 70 (normal <35), ALP 70 (normal <90) conclusion

Answer 41

- NOT alcohol bc AST:ALT not 2:1 | - statistically, more likely cause is fat (NASH)

Question 42

(IMPORTANT) when liver enzymes and bilirubin go up

Answer 42

- ALT and AST up acutely bc hepatocytes destroyed | - AP and bilirubin up after days bc have to be manufactured and excreted

Question 43

liver zones and fct

Answer 43

1 = near portal triad (duct, arteriole, venule): FA oxydation, glucose synthesis zone 2 = in between zone 3 = near central vein (glycogen synthesis and glycolysis + coag factors synth)

Question 44

injuries where in liver and meaning

Answer 44

- usually zone 1 | - zone 3 = toxic (get high INR, low glucose)

Question 45

UC patient with high enzymes and bilirubin

Answer 45

PSC

Question 46

high INR patient high bilirubin

Answer 46

zone 3 injured: toxic = fulminant (acute) liver failure

Question 47

acute vs chronic hepatitis

Answer 47

``` acute = 10 fold elevation of ALT chronic = 1.5-10 fold elevation of ALT ```

Question 48

high AP and GGT, normal INR, jaundice, palmar erythema, spider angiomata, splenomegaly (signs of portal htn) dx

Answer 48

PBC

Question 49

all normal except bilirubin of 56 dx

Answer 49

Gilbert's syndrome

Question 50

how to check liver problem cause with bilirubin

Answer 50

bilirubin < 250 = obstruction | bilirubin > 250 not obstruction

Question 51

end stage of any chronic liver disease

Answer 51

cirrhosis: regenerative nodules, fibrous septation | 2 stages: compensated and decompensated

Question 52

(EXAM) pathophgy of portal htn in cirrhosis

Answer 52

distorted sinusoidal architecture leads to increased resistance. backup in porto-caval anastomoses