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Diagnostics Exam 3- CMP, Inflammation, LFTs > LFTs > Flashcards

Flashcards in LFTs Deck (59)
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1
Q

Elevations typical of inflammation/hepatocellar damage

A

ALT
AST
may see GGT

(bilirubin, bilirubin direct, bilirubin indirect- only see if inflammation is severe)

2
Q

Elevations typical of cholestasis

A

Bilirubin
Bilirubin direct
Alkaline Phosphatase
may see GGT

3
Q

If GGT and ALP are elevated..

A

Source is likely liver

4
Q

Pattern indicative of reduced liver function

A

low albumin
low total protein

(may order separately:
PT- prolonged/high)

5
Q

Which is worse?
Very high ALT & AST with nl albumin & PT/INR

OR

Normal ALT & AST w. slightly low albumin & minimally high PT/INR?

A

Normal ALT & AST w. slightly low albumin & minimally high PT/INR

This means that the liver is not functioning!
No direct relationship between severity of liver disease & transaminase levels

6
Q

Liver inflammation/hepatocellular damage=

A

high ALT & AST

7
Q

Cholestasis=

A

high All phos & high Direct Bilirubin

8
Q

Reduced liver function=

A

High PT/INR, low albumin

9
Q

Common cause of cholestasis?

Sx?

A

Choledocholithiasis

pain- biliary colic
jaundice
clay-colored stools (light colored)
cola colored urine

10
Q

Isolated elevation in Indirect (unconjugated) bilirubin is often due to?

A

Gilbert syndrome

11
Q

Alkaline phosphate is derived from..?

A

liver & bone

12
Q

If only Alk phos is elevated, must get _____?

If elevated/not elevated, suggests..?

A

GGT

elevated= liver source
not elevated= bone source

13
Q

Common cause of reduced liver function= ?

A

Cirrhosis

14
Q

Explain why cirrhosis causes reduced liver function

A

Results from chronic liver disease ->
causes chronic inflammation/hepatocellular damage ->
scarring (fibrosis) - scarred liver does not function like healthy liver

15
Q

Signs and sx of cirrhosis

A
fatigue
portal HTN
ascites
jaundice
easily bruising/bleeding
16
Q

Can patients with nl ALT & AST levels have significant liver disease? Explain

A

Yes

Occurs in setting of chronic disease- like cirrhosis

17
Q

Is ALT or AST more specific to the liver?

A

ALT

18
Q

Risk factors for liver damage and disease

A
fam hx
EtOH
obesity
DM
hyperlipidemia
meds/supplements
autoimmune dz
Hepatitis risk factors
-IVDU
-high-risk sexual behavior
foreign travel
-hx of transfusions
-tattoos
19
Q

What is the easiest way to determine if a medication is causing elevation of ALT & AST?

A

Stop it and see if the lab value returns to nl

20
Q

DDx for elevated transaminases (AST & ALT)

A
hepatitis
alcoholic liver dz
fatty liver disease
meds
hemochromatosis

(celiac, hypothyroidism = uncommon)

21
Q

When to worry about elevated ALT & AST vs not

A

modest elevations are common- often asymptomatic

Worry if:
other liver tests abnormal
clinical signs and sx of disease
>3-5 fold elevation of any level
persistently abnormal for >6 months
22
Q

DDx for mildly elevated AST & ALT

A

-Fatty liver (hepatic steatosis)- assoc. with obesity, type 2 DM, HLD
EtOH related

23
Q

DDx for elevated AST

A

Alcoholic hepatitis
common bile duct obstruction
cholangitis

24
Q

DDx for ALT/AST elevation with:

AST:ALT ratio of >1

A

EtOH liver disease (especially if GGT >2x normal)

25
Q

DDx for ALT/AST elevation with:

AST:ALT ratio of < 1 (ALT higher)

A

acute or chronic viral hepatitis

NASH (nonalcoholic steatohepatitis)

26
Q

DDx for ALT/AST elevation with:

associated increased Alk Phos

A

Cholestatic disease (choledocholithiasis)

27
Q

NASH = ?

A

fatty infiltration + associated inflammation

28
Q

Prevalence of NAFLD (non alcoholic fatty liver disease)/NASH in population

A

11% (accounting for 75% of chronic liver dz)

29
Q

Risk factors for NAFLD/NASH

A

obesity
hypertriglyceridemia
insulin resistance & DM
Meds (estrogens, corticosteroids)

30
Q

What labs would be elevated in pt with NAFLD/NASH?

A

ALT or ALT & AST

31
Q

What is the usual initial imaging test you do to diagnose NAFLD/NASH?
why?

A

Ultrasound

increased echogenicity can detect steatosis

32
Q

General approach to management of NAFLD/NASH

A

weight loss in obese pts
Hep A & B vaccinations
avoid alcohol
treatment of risk factors of cardiovascular dz

33
Q

What is Hereditary Hemochromatosis?

And what population is it mostly seen in?

A

Hereditary disorder of iron metabolism
-autosomal recessive

Caucasians

34
Q

Classic triad in Hereditary Hemochromatosis

A

cirrhosis
DM
bronze skin pigmentation

35
Q

What are the steps to diagnosing Hereditary Hemochromatosis?

A
  1. Elevated ALT & AST, or 1st degree relative
  2. check serum transferrin saturation
  3. If TS <45= normal, no further eval
  4. If TS > 45 - check genotype
36
Q

If not identified, hereditary hemochromatosis can lead to?

A

cirrhosis leading to a hepatocellular carcinoma

37
Q

What is the most common pt to be diagnosed with autoimmune hepatitis?
Age/gender

A

40s-50s

female

38
Q

What is Wilsons disease?

A

very rare hereditary disorder of cellular copper transport

-autosomal recessive

39
Q

What is a notable physical feature of patients with Wilsons disease?

A

Kayser-Fleischer rings (in about 1/2 pts with dz)

40
Q

Other than elevated ALT/AST, what other lab abnormality would you see in a pt with Wilson disease?

A

Low ceruloplasim (the major copper-carrying protein)

41
Q

Approach to an asymptomatic pt with mildly elevated ALT/AST

A

Step 1
Check for risk factors for hepatitis, liver damage, & conditions assoc. with NAFLD/NASH

Step 2
Consider other causes of elevated ALT/AST (celiac, hypothyroidism, adrenal insufficiency)

Step 3
Consider screening for rare liver conditions (autoimmune hepatitis, Wison disease)

Step 4
Ultimately may need specialty consult- GI or Hepatologist

42
Q

Describe Hep A infection

what kind of hep, chronic/not, route

A
  • causes “infectious/ endemic hepatitis”
  • does not lead to chronic disease
  • spread fecal-oral route
43
Q

What are the main sx of Hep A?

A

fever and jaundice (looks like hepatitis)

44
Q

Management of Hep A

A

supportive care

post-exposure prophylaxis (vaccine)

45
Q

Prevention of Hep A

A
  • Hygiene- hand washing
  • vaccinate children between 12-23 months
  • vaccinate those who are at risk of complications from HAV (traveling, MSM, drug users, w/ chronic liver disease, contacts of people w/ HAV)
46
Q

What will labs show in pt with Hep A?

A

Elevated ALT & AST

Can also see elevated bilirubin

47
Q

When testing for Hep A, what is an good marker of acute or recent infection?

A

IgM anti-HAV antibodies

48
Q

Describe Hep B

transmission, chronic/not?

A

Transmitted by blood, sexual contact, parenteral contact

Leading cause of cirrhosis and hepatocellular carcinoma worldwide

49
Q

Hep B- Acute vs chronic sx

A

Acute: varies
Chronic: usually asymptomatic until late disease

50
Q

Prevention of Hep B

A
  • Avoid high risk behaviors

- Vaccination (infants, children, MSM, IVDU, people with HIV)

51
Q

What labs would you see n acute vs chronic Hep B?

A

Acute: Elevated ALT/AST (in the hundreds or thousands)

Chronic: Elevated ALT/AST (mildly elevated)

52
Q

What is Hep B surface antigen (ABsAg) and when is it highest?

A

Protein on surface of the virus

During incubation-beginning of acute phase (Infective phase)

53
Q

What is Hep B surface antibody (anti-HBs) appear and what does it indicate?

A
  • appears during recovery
  • usually indicates recent infection or immunity
  • also in vaccinated person
54
Q

When does Total Hep B core antibody appear and what does it indicate?

A

At onset of sx in acute phase and persists for life

Indicates previous or ongoing infection of HBV in undefined time frame

55
Q

What does IgM antibody to Hep B core antigen (IgM anti-HBc) indicate?

A

acute or recent infection with HBV (less than 6 months)

56
Q

If someone has anti-HBs + does not have anti-HBc, what does that indicate?

A

Immunity from vaccination

57
Q

What is Hep C the leading cause of?

A

leading cause of liver transplants in the U.S.

58
Q

How is Hep C transmitted?

A
  • IVDU (most common)
  • received donated blood
  • needle-stick injuries
  • birth (HVC-infected mother)

Can also be spread infrequently through:
sex
sharing personal items (toothbrush/razors)

59
Q

Explain the process of testing for HCV

A
  1. HCV antibody
  2. If +, check for HCV RNA
  3. If HCV RNA is +, pt has HCV. If HVC RNA not preset- infection might have cleared or HCV antibody was false +
    (Because Hep C does not provide immunity to re-infection!)