Enzymes

Question 1

Where is ALP found

Answer 1

intestine, liver, bone, placenta

also RBC surfaces

Question 2

Paget’s disease

Answer 2

ALP 10-25x the normal upper limit

Question 3

Osteomalacia, Rickets

Answer 3

ALP is 2-4x the normal upper limit

Question 4

Hyperparathyroidism

Answer 4

ALP is slightly - moderately increased

Question 5

Osteoporosis

Answer 5

ALP is normal or slightly increased

Question 6

Hepatobiliary Disease

Answer 6

ALP is 3-10x normal upper limit

Question 7

Hepatic cancer

Answer 7

ALP is 10-12x the normal upper limit

Question 8

Hepatitis and Cirrhosis

Answer 8

slight increase in ALP

Question 9

ALP measured absorbance

Answer 9

405 nm

alkaline pH ~10 is necessary

Question 10

ALP activators

Answer 10

Zn and Mg

Question 11

ALP inhibitors

Answer 11

phosphate, oxalates, citrate, EDTA

Question 12

ALP limitations

Answer 12

plasma/serum should be measured w/in 4 hours

increases with storage at 4 degrees and room temp

NO HEMOLYZED SPECIMENS

Question 13

Where is LD found

Answer 13

everywhere

Highest []s are heart, liver, skeletal muscles, RBCs, PLTs, lymph nodes

Question 14

Clinical significance of LD

Answer 14

non-specific indicator

Question 15

LD and anemia

Answer 15

increased serum LD

hemolytic and megaloblastic anemias

Question 16

LD and liver disease

Answer 16

increased in viral hepatitis, cirrhosis, liver cancer

Question 17

LD and heart disease

Answer 17

increased in myocardial infarction

Question 18

LD Methodology

Answer 18

NAD ====> NADH

observe increase in Abs at 340 nm

pH should be 8.3 - 8.9

Question 19

LD coenzyme

Answer 19

NAD+

Question 20

LD limitations

Answer 20

serum preferred, PLTs can interfere

store at room temp

NO HEMOLYZED SPECIMENS

Question 21

Where is ALT found

Answer 21

liver and kidneys

Question 22

ALT and viral hepatitis and acute hepatic necrosis

Answer 22

increases 10-40x normal upper limit

Question 23

ALT and acetaminophen toxicity

Answer 23

> 85x normal upper limit

Question 24

ALT and NAFLD, metabolic syndrome

Answer 24

Elevated []s may observed

Question 25

ALT methodology

Answer 25

2 step reaction, 2nd step done by LD NADH =====> NAD+ Measure Abs at 340 nm pH 7.3 - 7.8

Question 26

ALT coenzyme

Answer 26

pyridoxal 5' phosphate (vitamin B6)

Question 27

ALT limitations

Answer 27

should be measured same day stable at -70 hemolysis may falsely elevate result due to endogenous LD

Question 28

where is GGT found

Answer 28

kidney bile ducts of liver pancreas intestine

Question 29

GGT and hepatobiliary disease

Answer 29

indicator, especially for bile obstruction

Question 30

GGT and alcohol hepatitis

Answer 30

elevated

Question 31

Can GGT help in determining if observed [ALP] elevations are due to hepatobiliary disease or skeletal disease?

Answer 31

Yes, GGT is normal in skeletal disorders and pregnancy

Question 32

GGT methodology

Answer 32

measure Abs at 405 nm pH at 8.2

Question 33

GGT activator

Answer 33

Mg

Question 34

GGT inhibitors

Answer 34

citrate oxalate fluoride

Question 35

GGT limitations

Answer 35

non-hemolyzed preferred GGT higher in newborns ethanol, warfarin, phenobarbital, and phenytoin can falsely elevate

Question 36

where is CK found

Answer 36

muscle, heart, brain

Question 37

CK and muscle

Answer 37

increased in all forms of muscular dystrophy increased in muscle trauma, rhabdomyolysis

Question 38

CK and heart

Answer 38

increased in cardiac disorders

Question 39

CK methodology

Answer 39

3 step reaction measure Abs at 340 nm pH is 6.8

Question 40

CK activator

Answer 40

Mg

Question 41

CK coenzyme

Answer 41

ATP

Question 42

CK inhibitors

Answer 42

all anticoagulants other than heparin Mn, Ca, Zn, Cu, excess Mg

Question 43

CK limitations

Answer 43

stable up to 48 hours at 4 degrees Gross hemolysis interferes with second step in reaction (hexokinase)

Question 44

where is AMY found

Answer 44

salivary glands, pancreas, ovaries, fallopian tubes, lungs

Question 45

AMY and salivary gland

Answer 45

increased with inflammation (mumps)

Question 46

AMY and acute pancreas

Answer 46

increases 5 to 8 hours after onset of symptoms, peaks at 24 hrs, back to normal in 3-5 days (lipase is more specific)

Question 47

AMY and intrabdominal disorders (ectopic pregnancy, biliary tract disease, appendicitis, intestinal blockage)

Answer 47

increased

Question 48

AMY methodology

Answer 48

4 step reaction NAD ====> to NADH measure at 340 nm pH 6.9-7.0

Question 49

AMY activator

Answer 49

Ca is needed 100%

Question 50

AMY inhibitors

Answer 50

all coagulants except heparin

Question 51

AMY limitations

Answer 51

serum and urine AMY stable at room temp in vitro, plasma triglycerides inhibit activity Morphine and opiates falsely increase

Question 52

where is LIP found

Answer 52

pancreas, stomach, small intestine

Question 53

LIP and acute pancreatitis

Answer 53

used to diagnose increases 4-8 hours after onset of symptoms, peaks at 24 hrs, normal at 7-14 days >3x normal upper limit

Question 54

How is LIP measured

Answer 54

colorimetric, turbidimetric, titrimetric

Question 55

LIP cofactors

Answer 55

colipase and bile salts

Question 56

LIP limitations

Answer 56

stable in serum at room temp for one week hemolysis should be avoided lipemia and bilirubin is method dependent