ASCP HACKS - Clinical Chemistry: Questions With
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Terms in this set (162)
Heparin on ice >> ammonia, blood gas & lactic acid.
Anticoagulants NaF >> NOT for BUN (inhibits urease)
EDTA >> Not for Na+ or K+ (EDTA contains Na and K)
For digestion, metabolism & regulation.
End product of carbohydrate digestion in the intestine -
to provide energy.
Specimen collection & handling:
Carbohydrates: Glucose ~ Decrease approx. 10mg/dl or 7% per hour in whole
blood.
~ Fairly stable if refrigerated.
~ Normal range of fasting Glu plasma/serum (70-99
mg/dl).
~ Arterial & capillary values are 2-3 mg/dL higher.
G-A-G-C-H-E-T all raise glucose levels.
G Glucagon: made by alpha cells of pancreas.
A ACTH: made by anterior pituitary gland.
G Growth hormone: aka somatotropin, made in anterior
Hormones that affect
pituitary.
serum glucose values.
C Cortisol: made by adrenal cortex.
H Human placental lactogen: made by placenta
E Epinephrine: made by adrenal medulla
T T3, T4: made by thyroid gland.
, Fasting Plasma Glu:
~ Prediabetes = 100-125 mg/dl
~ Norm = < 126 mg/dl
~ DM = > 126 mg/dl
Casual Plasma Glu:
Test interpretation to ~ DM = > 126 mg/dl
diagnose Diabetes Mellitus OGTT:
(DM) ~ 2 hr PG during OGTT = 200 mg/dL or higher indicate
DM.
A1C:
~ Prediabetes = 5.7 to 6.4%
~ Norm = < 5.6%
~ DM = > 6.5%
Average glu level for past 90 days (3 months):
HBA1c
expressed as % and convert to eAG.
Intermediate-term control; glu attaches to proteins
Fructosamine
including albumin (reflects 2-3 weeks glucose level)
Urinary albumin formerly Detects small amounts of albumin in urine to assess
"microalbumin" early renal damage.
Pro-insulin cleaved to give C-peptide and insulin;
C-Peptide reflects endogenous insulin production if patient is on
insulin therapy.
1. Glucose-oxide
~ Glu oxidase converts glu to gluconic acid + H2O2
~ Peroxidase converts H2O2 into oxygen
Glucose methods:
enzymatic 2. Hexokinase - reference method
~ Coupled rxn;
Glu + ATP >>Hexokinase>> G6P + ADP
G6P + NADP >>G6PD>> NADPH measured @ 340 nm
~ Xylose absorbed & excreted into the urine without
need of pancreatic enzymes.
Xylose absorption test
~ Helps distinguish between intestinal malabsorption &
pancreatic-based malabsorption.
~ Indicator of O2 deprivation.
~ Buildup is lactic acidosis.
Lactic acid
~ Critical Collection: Separate and refrigerate as soon as
possible; no exercise before collection.
, The protein portion of lipoprotein.
Apolipoprotein A = major protein of HDL
Apoliproprotein B (B100 or B48) = present in all
atherogenic lipoprotein.
Lipoprotein classes:
Chylomicrons transport exogenous
VLDL transport endogenous
LDL cholesterol to cells
HDL Cholesterol out of cells
Exogenous lipids are obtained from the diet. They come
Apoliproteins
from the fats and oils present in food. They provide
energy and essential fatty acids and are involved in the
absorption of fat-soluble vitamins (A, D, E, K).
Endogenous lipids are synthesized within the body.
They are produced by the liver and other tissues. They
are critical for maintaining cell membrane integrity,
producing energy when needed, synthesizing
hormones, and storing energy in adipose tissue.
Lightest to heaviest;
Chylomicrons < VLDL < LDL < HDL
Goal values:
HDLc > 35 mg/dl
Non-fasted lipid screening
TAG < 150 mg/dl, TAG (triglycerides)
values
LDLc < 100 mg/dl
Total cholesterol (TC) < 200 mg/dl
~ if TAG > 400 mg/dl, the Friedewald equation CANNOT
be used.
LDLc = total cholesterol - HDLc - TAG/5
Friedewald Equation:
estimates the cholesterol Cardiac disease risk factors:
content of LDL fraction in 1. Age (M>45, F>55)
the blood. 2. Family History
3. Cigarette smoking
4. Hypertension (systolic>120)
5. < 40 mg/dl HDLc
6. DM
, ~ Phenylketonuria: rare inherited disorder that causes
amino acid phenylalanine to build up in the body. PKU
caused by a change in phenylalanine hydroxylase gene
that helps create the enzyme needed to break down
phenylalanine.
~ Causes high phenylalanine in blood and high phenyl
Amino acids >>
compound in urine.
aminoaciduria, PKU
Screening test:
A. Thin-layer chromatography w/ ninhydrin.
B. Urine color test
C. Guthrie bacterial inhibition assay for PKU: + when B.
subtilis grows.
Homocysteine - High levels associated with risk of CVD,
Amino Acids in blood? stroke, alzheimers & osteoporosis (deficiency in vit. B6,
B12 & folic acid).
~ Most are synthesized & catabolized in the liver.
~ Basic unit is amino acids linked together by amide
Proteins? bonds.
~ Breakdown produces ammonia & urea which are
eliminated by the kidneys.
~ Kjeldahl (reference method): measures N content in
protein using acid digestion; difficult to perform and
infrequently used.
Serum total protein
~ Biuret rxn most frequently used.
method?
~ Depends on presence of > peptide bonds which react
to form a purple complex with copper salts in Alkaline
soln.
Dye-binding methods for albumin:
Specific serum protein
1. Bromcresol Green (BCG).
methods?
2. HABA (4'-Hydroxyazobenzene-benzoic acid.
1. Dye >> Coomassie Brilliant Blue.
2. Turbidimetric methods with acids that precipitate
Urine & CSF total protein
protein:
methods?
~ Sulfosalicylic acid (SSA)
~ Trichloroacetic acid (TCA)
Objective Solutions
Save
Terms in this set (162)
Heparin on ice >> ammonia, blood gas & lactic acid.
Anticoagulants NaF >> NOT for BUN (inhibits urease)
EDTA >> Not for Na+ or K+ (EDTA contains Na and K)
For digestion, metabolism & regulation.
End product of carbohydrate digestion in the intestine -
to provide energy.
Specimen collection & handling:
Carbohydrates: Glucose ~ Decrease approx. 10mg/dl or 7% per hour in whole
blood.
~ Fairly stable if refrigerated.
~ Normal range of fasting Glu plasma/serum (70-99
mg/dl).
~ Arterial & capillary values are 2-3 mg/dL higher.
G-A-G-C-H-E-T all raise glucose levels.
G Glucagon: made by alpha cells of pancreas.
A ACTH: made by anterior pituitary gland.
G Growth hormone: aka somatotropin, made in anterior
Hormones that affect
pituitary.
serum glucose values.
C Cortisol: made by adrenal cortex.
H Human placental lactogen: made by placenta
E Epinephrine: made by adrenal medulla
T T3, T4: made by thyroid gland.
, Fasting Plasma Glu:
~ Prediabetes = 100-125 mg/dl
~ Norm = < 126 mg/dl
~ DM = > 126 mg/dl
Casual Plasma Glu:
Test interpretation to ~ DM = > 126 mg/dl
diagnose Diabetes Mellitus OGTT:
(DM) ~ 2 hr PG during OGTT = 200 mg/dL or higher indicate
DM.
A1C:
~ Prediabetes = 5.7 to 6.4%
~ Norm = < 5.6%
~ DM = > 6.5%
Average glu level for past 90 days (3 months):
HBA1c
expressed as % and convert to eAG.
Intermediate-term control; glu attaches to proteins
Fructosamine
including albumin (reflects 2-3 weeks glucose level)
Urinary albumin formerly Detects small amounts of albumin in urine to assess
"microalbumin" early renal damage.
Pro-insulin cleaved to give C-peptide and insulin;
C-Peptide reflects endogenous insulin production if patient is on
insulin therapy.
1. Glucose-oxide
~ Glu oxidase converts glu to gluconic acid + H2O2
~ Peroxidase converts H2O2 into oxygen
Glucose methods:
enzymatic 2. Hexokinase - reference method
~ Coupled rxn;
Glu + ATP >>Hexokinase>> G6P + ADP
G6P + NADP >>G6PD>> NADPH measured @ 340 nm
~ Xylose absorbed & excreted into the urine without
need of pancreatic enzymes.
Xylose absorption test
~ Helps distinguish between intestinal malabsorption &
pancreatic-based malabsorption.
~ Indicator of O2 deprivation.
~ Buildup is lactic acidosis.
Lactic acid
~ Critical Collection: Separate and refrigerate as soon as
possible; no exercise before collection.
, The protein portion of lipoprotein.
Apolipoprotein A = major protein of HDL
Apoliproprotein B (B100 or B48) = present in all
atherogenic lipoprotein.
Lipoprotein classes:
Chylomicrons transport exogenous
VLDL transport endogenous
LDL cholesterol to cells
HDL Cholesterol out of cells
Exogenous lipids are obtained from the diet. They come
Apoliproteins
from the fats and oils present in food. They provide
energy and essential fatty acids and are involved in the
absorption of fat-soluble vitamins (A, D, E, K).
Endogenous lipids are synthesized within the body.
They are produced by the liver and other tissues. They
are critical for maintaining cell membrane integrity,
producing energy when needed, synthesizing
hormones, and storing energy in adipose tissue.
Lightest to heaviest;
Chylomicrons < VLDL < LDL < HDL
Goal values:
HDLc > 35 mg/dl
Non-fasted lipid screening
TAG < 150 mg/dl, TAG (triglycerides)
values
LDLc < 100 mg/dl
Total cholesterol (TC) < 200 mg/dl
~ if TAG > 400 mg/dl, the Friedewald equation CANNOT
be used.
LDLc = total cholesterol - HDLc - TAG/5
Friedewald Equation:
estimates the cholesterol Cardiac disease risk factors:
content of LDL fraction in 1. Age (M>45, F>55)
the blood. 2. Family History
3. Cigarette smoking
4. Hypertension (systolic>120)
5. < 40 mg/dl HDLc
6. DM
, ~ Phenylketonuria: rare inherited disorder that causes
amino acid phenylalanine to build up in the body. PKU
caused by a change in phenylalanine hydroxylase gene
that helps create the enzyme needed to break down
phenylalanine.
~ Causes high phenylalanine in blood and high phenyl
Amino acids >>
compound in urine.
aminoaciduria, PKU
Screening test:
A. Thin-layer chromatography w/ ninhydrin.
B. Urine color test
C. Guthrie bacterial inhibition assay for PKU: + when B.
subtilis grows.
Homocysteine - High levels associated with risk of CVD,
Amino Acids in blood? stroke, alzheimers & osteoporosis (deficiency in vit. B6,
B12 & folic acid).
~ Most are synthesized & catabolized in the liver.
~ Basic unit is amino acids linked together by amide
Proteins? bonds.
~ Breakdown produces ammonia & urea which are
eliminated by the kidneys.
~ Kjeldahl (reference method): measures N content in
protein using acid digestion; difficult to perform and
infrequently used.
Serum total protein
~ Biuret rxn most frequently used.
method?
~ Depends on presence of > peptide bonds which react
to form a purple complex with copper salts in Alkaline
soln.
Dye-binding methods for albumin:
Specific serum protein
1. Bromcresol Green (BCG).
methods?
2. HABA (4'-Hydroxyazobenzene-benzoic acid.
1. Dye >> Coomassie Brilliant Blue.
2. Turbidimetric methods with acids that precipitate
Urine & CSF total protein
protein:
methods?
~ Sulfosalicylic acid (SSA)
~ Trichloroacetic acid (TCA)
