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Flashcards in Laboratory Medicine Deck (54)
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

31

What is the main agent of intravascular osmotic pressure?

Albumin

32

How many mg / kg of albumin are produced by a normal adult daily?

150-250 mg / kg

33

What leads to pitting edema and why?
a) increased albumin
b) decreased albumin

b) decreased albumin
lack of albumin causes water to spill out from interstitial components

34

How does albumin loss result from severe burns?

Skin is the most important extra storage for albumin

35

Nephrotic syndrome results in ______uria

Proteinuria

36

Which of the following would be NOT indicated by decreased albumin?
a) end stage liver disease
b) Celiac disease
c) protein malnutrition
d) acute dehydration

acute dehydration - only clinical thing indicated by increased albumin

37

Why does Celiac disease contribute to decreased albumin?

If you cannot absorb protein, you cannot make it

38

What is Kwashiorkor and why does it result in abdominal edema?

This is a disease that happens in a rice-only diet. There is protein malnutrition --> no albumin synthesis --> weak osmotic pressure --> fluid from tissue diffuses into abdomen

39

What test should be used to evaluate increase or decrease in globulin?

Serum electrophoresis

40

How many liters of blood does the kidney process daily?

200L

41

What percentage of daily blood that kidney filters is removed as waste or excess H2O?

1% (2L out of 200)

42

______ is produced by the kidneys and stimulates RBC production in bone marrow

Erythropoietin

43

______ is produced by the kidneys and used in regulation of blood pressure?

Renin

44

The active form of which vitamin is produced by the kidneys?

Vitamin D

45

Which kidney function test measures GFR (glomerular filtration rate)?

Creatinine

46

Elevated BUN or creatinine signals what?

Body not excreting efficiently

47

Blood in urine may signal what in adults? What if they are older?

Adults - kidney infection
Older - bladder ca

48

Where is brain natriuretic peptide secreted from?

Heart ventricles

49

Brain natriuretic peptide is secreted in response to what?

Excess stretching of heart ventricles

50

What does brain natriuretic peptide signal the body to do? (2 pathways)

1) Vasodilation to lower blood pressure --> assist heart
2) Signals kidneys to produce urine --> decrease volume

51

What is traumatic tap in lumbar punctures?

Blood in CSF due to trauma from actual lumbar puncture not from traumatic brain bleed

52

Why would estrogen levels be an inappropriate test for menopause?

Estrogen levels fluctuate quite a bit pre and post menopause

53

What brown substance is produced from urobilinogen in the intestines?

stercoblin

54

The kidneys produce which vitamin? Is this a protein or hormone?

Vitamin D aka Calcitrol, hormone