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Flashcards in Laboratory Medicine Deck (54)
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1

What are the 5 main electrolytes in body fluid?

Na+, Cl-, Mg2+, Ca2+, K+

2

What are the 5 functions of hepatocytes?

1) Drug and toxin metabolism
2) Aid digestion via biliary system
3) Protein synthesis and secretion
4) Energy storage (glycogen)
5) Transformation and clearance

3

How can acetaminophen cause liver necrosis?

Liver produces a toxic metabolite of APAP --> too much leads to necrosis

4

What is the main job of the liver?

Take insoluble compounds and make soluble for excretion

5

Pyridoxal phosphate (AKA Vitamin B6) plays a role in what types of reaction in the liver?

It is a coenzyme of all transamination reactions

6

What is the function of transaminases?

Transfer amine groups to allow for excretion

7

Is ALT or AST more specific for liver injury and why?

ALT is more specific because found in cytosol of liver - AST is found in both cytosol and mitochondria of liver along with many other organs

8

What four things cause elevated AST/ALT?

Viral hepatitis, fatty liver (sometimes), toxins (including medications), strenuous exercise

9

Alk phos tells you about the integrity of what?

Biliary tree

10

What are the components of total protein?

Albumin and globulin

11

Bilirubin is a ____________ of older blood cells

Degradation product

12

Bilirubin buildup can be toxic to which organ?

Brain

13

What are old red blood cells a source of?

Hemeproteins

14

What cell breaks down heme to bilirubin?

Macrophages

15

How is unconjugated bilirubin transported via blood to liver?

It is complexed with albumin

16

Once bilirubin is uptaken by the liver, what is it conjugated with?

Glucaronic acid

17

Where is conjugated bilirubin secreted into following the liver?

Into bile then into intestine

18

What happens to conjugated bilirubin in the intestine? (two steps)

Bacteria remove glnucaronic acid, then bilirubin is converted to urobilinogen

19

What are the three pathways urobilinogen may take from intestine?

1) Some reabsorbed from gut and enters portal blood where transported to kidney --> excreted in urine as yellow "urobilin"
2) participates in enterohepatic urobilinogen cycle
3) Oxidized by intestinal bacteria to brown stercoblin

20

In the kidney, urobilinogen is converted to what yellow substance?

Urobilin

21

If there is elevation in indirect bilirubin, would there be a defect in
a) pre hepatic
b) post hepatic
pathway?

a) pre hepatic
indirect = unconjugated

22

If there is elevation in direct bilirubin, would there be a defect in
a) pre hepatic
b) post hepatic
pathway?

b) post hepatic
direct = conjugated

23

Elevations in indirect bilirubin would NOT result from which of the following?
a) Increased production of non-conjugated bilirubin
b) Impaired conjugation of bilirubin
c) Increased hepatic uptake of bilirubin

c) is wrong
results from these 3:
1) increased production
2) impaired conjugation
3) impaired hepatic uptake

24

Would hemolysis result in
a) elevated indirect bilirubin
b) elevated direct bilirubin

a) elevated indirect
- more unconjugated bilirubin present

25

What is Kernicterus?

Elevation in indirect bilirubin in neonate and infants which leads to severe CNS deficiencies

26

Crippler/Najjar Syndrome and Gilbert's Dz both have what in common?

They are caused by problems with enzymatic action that lead to elevation of indirect bilirubin

27

What would cause accumulation of direct bilirubin?
a) Biliary obstruction
b) Biliary dysregulation
c) Increased secretion of conjugated bilirubin into bile

a) biliary obstruction

28

Which of the following diseases would NOT be indicated by elevated conjugated bilirubin?
a) Crigler/Najjar Syndrome
b) Gilbert's Disease
c) Hepatitis
d) Dubin-Johnson Syndrome
e) two of the above

E - A and B

29

Jaundice is the result of high amounts of ________ being deposited

Bilirubin

30

True or false: lack of albumin can cause jaundice

True, albumin does not bind bilirubin --> bilirubin not excreted --> jaundice