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Flashcards in Clinical Lab in GI Disease Deck (44)
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1

What are the diagnostic criteria for acute pancreatitis?

Need two of three:

Abdominal pain characteristic of disease

amylase and/or lipase at least 3x the ULN

characteristic imaging findings

2

Which is better for pancreatitis and why: amylase or lipase?

lipase because it is more sensitive and more specific

also remains elevated longer than amylase

IN FACT: CURRENT REC IS FOR LIPASE ALONE

3

What are some other causes for elevated pancreatic enzymes?

macroamylasemia/macrolipasemia
renal failure
acute appendicitis
cholecystitis
intestinal ischemia/obstruction
peptic ulcer disease
gynecological disease
diabetes (esp lipase)
parotid/salivary gland (amylase only)

4

What are the two most common causes of acute pancreatitis?

gallstones and alcohol

5

What are some other less common causes of acute pancreatitis?

post-ERCP, trauma/injury
Genetic - like CF mutations
Drugs (azathioprine, sulfonamides, NSAIDs, steroids, tetracycline)
Viral infections (mumps, rubella, EBV, CMV, hepatitis)
Hypertrigliceridemia
Hypercalcemia

6

What are the first tier LFT labs?

transaminases
bilirubin
alk phos
GGT
albumin
prothrombin time/INR

7

What is the general pattern of liver labs in hepatocellular injury/necrosis?

ALT and AST significantly elevated, moreso than alk phos

8

What is the general pattern of liver labs in cholestatic disease?

alk phos elevated higher than ALT/AST

9

What is the general pattern of liver labs in infiltrative liver disease?

elevated AP with either normal or just slightly elevated AST/ALT

10

Which transaminase is more specific for liver disease?

ALT

AST is also found in muscle and red cells, so with extensive muscle breakdown, both ALT and AST will rise

11

Which transaminase has a longer half-life?

ALT

(So Liver and Longer)

12

Where on the cell is alk phos located?

on the hepatocyte membrane bordering the bile canaliculi, which is why it elevated in obstructive disease

13

Where in the body are other alk phos isoemzymes located?

bone and placenta

also elevated in other GI and kidney diseases

14

What can you use to confirm a liver course of an elevated alk phos?

GGT - there are few reasons to order a GGT other than this!

15

What are the main causes of acute rises in transaminases?

Viral hepatitis
Drug-induced hepatitis
alcoholic hepatitis
Ishcemic "shock liver"
acute ductal obstruction
autoimmune hepatitis
Wilson's disease

16

ALT is often in the thousands with acute hepatitis. If it's over 5,000 U/L, though, what should you consider?

Acetaminophen
hepatic ischemia
unusual viruses like HSV

17

What are the four main causes of chronic hepatitis?

Hep C
Hep B
NASH
Alcoholic liver disease

18

What is the time cutoff for hepatitis to be called chronic?

over 3 months

19

What are some common causes of cholestasis?

Stones
Primary biliary cholangitis
primary sclerosing cholangitis
drug-induced stasis
infiltrative/malignancy
severe inflammation

20

Which suggests liver disease: elevated unconjugated bilir (indirect) or elevated conjugated bili (direct)?

conjugated (direct)

elevations in unconjugated (indirect) suggest hemolysis

21

Jaundice will become visible at what bili level?

>2.5 mg/dL

22

Can bilirubin help you determine whether liver disease is hepatocellular, cholestatic or infiltrative?

not really

23

What are some causes for unconjugated hyperbilirubinemia besides hemolysis?

resorption of large hematoma
ineffective erythropoiesis (like B12 def)
neonatal physiologic hyperbilirubinemia
Gilbert syndrome

24

What is the typical pattern of LFTs in alcoholic hepatitis?

AST > 2 x ALT
but AST less than 400 UL

25

What are the two main autoantibodies seen in autoimmune hepatitis?

type 1 with anti-smooth muscle and antinuclear

type 2 with liver-kidney microsome type 1

26

Who gets PBC and how do they present?

middle aged women

presenting with fatigue and pruritus

27

What will labs look like in PBC?

increased alk phos
increased IgM
Fal soluble bitamin deficiencyes
high HDL
later increased Bili

28

If you did a biopsy of a liver with PBC, what would you see?

granulomatous infiltration of the septal bile ducts

29

What is the main antibody seen in PBC?

anti-mitochondrial antibodies

30

What symptoms occur in stage I of acetaminophen toxicity?

anorexia
nausea
vomiting