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Clinical Chemistry
Gregory S. Travlos, DVM, DACVPNational Institute of Environmental Health Sciences
Research Triangle Park, NC 27709919-541-0653
AbbreviationsAChE = acetylcholinesterase
ALB = albumin
ALP = alkaline phosphatase
ALT = alanine aminotransferase
AST = aspartate aminotransferase
BA or TBA = total bile acids
Bili or Bil (T or D) = total or direct bilirubin
BUN or UN = urea nitrogen
BuChE = butyrylcholinesterase
Chol = cholesterol
CK or CPK = creatine kinase
Cre or Creat = creatinine
Glu = glucose
Glob = globulin
LDH = Lactate dehydrogenase
NAG = n-acetyl-glucoaminidase
SDH = sorbitol dehydrogenase
Tn or cTn = troponin (I or T); c = cardiac
T pro = total protein
Trig = triglycerides
Clinical ChemistryThe analysis of individual constituents,
proteins, enzymes, nutrients, waste products, metabolites, hormones, etc. in blood or body fluids that provides information regarding the function or integrity of a tissue, organ or organ system
While almost anything may be analyzed, the efficacy of a test depends on its specificity and sensitivity to detect pathological change
Analytical Procedures/MethodsToo numerous to cover
• Photometry• Fluorometry • Luminometry • Spectrometry • Nephelometry• Electrophoresis• Chromatography • Isotopic (RIA/IRMA) and non-isotopic (ELISA/EIA)
immunoassay
Considerations for Blood CollectionSerum: whole blood collected in a container without
anticoagulant• Plasma is acceptable for some assays (heparin)• Samples from indwelling catheters are usually acceptable
For serum: allow blood to clot for 30 to 60 minutes
Separate serum for red cells into a clean plastic container• Avoid artifact due to prolonged storage on red cells (e.g., LDH)
Sources of VariationDiet
• NIH-07 vs. NTP 2000
= NTP 2000
= NIH-07
Diet: NIH-07 v. NTP-2000Analyte NIH-07 NTP-2000ALT (IU/L)
Males 56.5 90.0 Females 47.5 77.0
BUN (mg/dL)
Males 20.0 15.0 Females 20.5 14.8
Switching diets resulted in an approximately 60% increase in control animal serum ALT activity and a 26% decrease in serum BUN concentration.
Sources of VariationDiet
• NIH-07 v NTP 2000
Fasting• Glucose• Alkaline phosphatase
Sources of VariationDiet
• NIH-07 v NTP 2000
Fasting• Glucose• Alkaline phosphatase
Diurnal variation• Hormones
Estradiol Values in Cycling Rats and Mice
0
10
20
30
40
50
60
Early Proest Late Proest Estrus Metestrus Diestrus Diestrus 2
Estradiol (ng/mL)
F344
SD
B6
CD-1
Circadian Rhythm of Serum Melatonin in Female F344 Rats
0.0
50.0
100.0
150.0
200.0
250.0
06:00 11:30 12:30 13:30 14:30 15:30 16:30 17:30 18:30 19:30 20:30 21:30 22:30 23:30 00:30
Time
pg/mL
Serum Melatonin after Five 1-Minute Light Exposures in Female F344 Rats
0.0
50.0
100.0
150.0
200.0
250.0
06:00 11:30 12:30 13:30 14:30 15:30 16:30 17:30 18:30 19:30 20:30 21:30 22:30 23:30 00:30
Time
pg/mL
12/12 control
1-day exposure
Sources of VariationDiet
• NIH-07 v NTP 2000
Fasting• Glucose• Alkaline phosphatase
Diurnal variation• Hormones
Analytical Methods & Sample Collection/Handling Techniques• Animal handling - rough handling: increased creatine kinase release• In vitro Hemolysis - assay interference: bilirubin • Method selection - troponin
Troponin
Comparison of cTn Measurement in the Comparison of cTn Measurement in the Sprague Dawley RatSprague Dawley Rat
cTn
IcT
nI (
ng
/mL
)(n
g/m
L)
cTn
T (
ng
/mL
)cT
nT
(n
g/m
L)
NegNeg LowLow MedMed HighHigh00
11
22
33
44
55
66
00
55
1010
1515
2020
2525
3030
Roche Elecsys 2010
Rat Troponin EIA
DPC Immulite
OCD Vitros ECi
Dade Dimension RxL
Beckman Access
Bayer Advia Centaur
Tosoh AIA 600 II
Abbott Architect
0.000.00
0.050.05
0.100.10
0.150.15
0.200.20
0.250.25
00
55
1010
1515
2020
Comparison of cTn Measurement in the Comparison of cTn Measurement in the BeaglecT
nI (
ng
/mL
)cT
nI (
ng
/mL
)
cTn
T (
ng
/mL
)cT
nT
(n
g/m
L)
NegNeg LowLow MedMed HighHigh
Roche Elecsys 2010
Dog Troponin EIA
DPC Immulite
OCD Vitros ECi
Dade Dimension RxL
Beckman Access
Bayer Advia Centaur
Tosoh AIA 600 II
Abbott Architect
Sources of VariationDiet
• NIH-07 v NTP 2000
Fasting• Glucose• Alkaline phosphatase
Diurnal variation• Hormones
Analytical Methods & Sample Collection/Handling Techniques• Animal handling - rough handling: increased creatine kinase release• In vitro Hemolysis - assay interference: bilirubin • Method selection - troponin• Multiple factors - cholinesterase
Cholinesterase AssayTwo types of cholinesterase
acetylcholinesterase (AChE; RBCs)butyrylcholinesterase (BuChE; liver)
For rat plasma: AChE:BuChE ratio approximately 1.2:1
Spectrophotometric assay: but different assays use different substratesdinitrobenzoic acidacetylcholinepropionylthiocholinebutyrylthiocholine
And the different cholinesterases have varying affinities for the different substrates
There are species differencesFor RBC and serum: human > dog > rat; platelets: rat > human
There can be sex differencesFor rat: female > male
Serum AChE (IU/L)Propargyl Alcohol Control 64 ppm
Males 1071 778
Serum AChE (IU/L)Propargyl Alcohol Control 64 ppm
Males 1071 778
Suggested an approximate 30% enzyme inhibition
Serum ChE (IU/L)Propargyl Alcohol Control 64 ppm
Males 1071 778
Suggested an approximate 30% enzyme inhibition
PTC assay BTC assayUntreated0.1 mM1.0 mM10.0 mM
Assays: normal male rat serum; 2.5 hour incubation; performed in duplicate
Serum ChE (IU/L)Propargyl Alcohol Control 64 ppm
Males 1071 778
Suggested an approximate 30% enzyme inhibition
PTC assay BTC assay
Untreated 876 272 0.1 mM 795 289 1.0 mM 825 299 10.0 mM 836 262
Assays: normal male rat serum; 2.5 hour incubation; performed in duplicate
NTP Core Clinical Chemistry ProfileLiver
• Alanine Aminotransferase• Sorbitol Dehydrogenase• Alkaline Phosphatase• Total Bile Acids
Kidney• Urea Nitrogen• Creatinine
Protein• Total protein• Albumin
Muscle• Creatine Kinase
Evaluation of LiverAlanine Aminotransferase (ALT, SGPT)
• Greatest activity - hepatocytes; also found in skeletal/cardiac muscle• Biological half-life - varies (~48-60 hours)• Sample stability - stabile at room, refrigerated and frozen temperatures• Can be induced (eg., glucocorticoids)• Increased - hepatocellular injury, induction, muscle injury • Decreased - enzyme inhibition (cyclosporin)
Sorbitol Dehydrogenase (SDH)• Greatest activity - hepatocytes; also found in testes• Biological half-life - short (≤6 hours)• Sample stability - not as stabile; in rats, stabile refrigerated (~2 days)• Not known to be induced• Only known cause for serum increase - hepatocellular injury or leakage
Evaluation of Liver - cont.Aspartate Aminotransferase (AST, SGOT)
• Greatest activity - found in numerous tissues (not specific for liver injury)• Biological half-life - short (~15-24 hours)• Sample stability - stabile at room, refrigerated and frozen temperatures• Red blood cells contain significant amounts (hemolysis - falsely elevates)• Used in past to detect hepatocellular injury (still used for large animals); used
for muscle injury
Alkaline Phosphatase (ALP)• Greatest activity - liver, bone intestine, kidney, placenta• Biological half-life - isoenzymes of different tissues highly variable• Sample stability - stabile in serum; not in urine• Can be induced (eg., glucocorticoids, phenobarbital, dieldrin)• Increased - cholestasis, drug induction, increased osteoblastic activity, cancer• Decreased - decreased food intake (rats)
Evaluation of Liver - cont.Bilirubin, direct (conjugated) and total (Dbili & Tbili)
• Breakdown product of hemoglobin• Liver removes unconjugated bilirubin (insoluble) from plasma, conjugates it
(glucuronide - renders bilirubin water soluble) and secreted into bile• Sample stability - stabile serum and urine• Increased - Retention-type (hemolysis, decreased hepatic uptake);
Regurgitation-type (cholestasis)
Bile Acids (TBA)• Produced by liver - cholic and chenodeoxycholic (primary bile acids)• Taurine or glycine conjugated and secreted into bile• Intestinal bacterial modification produces deoxycholic and lithocholic acids• Increased - cholestasis, decreased hepatic uptake/conjugation, hepatic injury • Decreased - altered enterohepatic recirculation
Liver Case ExamplesRef Value 1
ALT 30-55 IU/L 34
SDH 10-20 IU/L 16
ALP 250-350 IU/L 157
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 0.2
Dbili 0.05-0.2 mg/dL 0.1
Liver Case ExamplesRef Value 1
ALT 30-55 IU/L 34
SDH 10-20 IU/L 16
ALP 250-350 IU/L 157
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 0.2
Dbili 0.05-0.2 mg/dL 0.1
• Case 1: Decreased ALP
Liver Case ExamplesRef Value 1
ALT 30-55 IU/L 34
SDH 10-20 IU/L 16
ALP 250-350 IU/L 157
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 0.2
Dbili 0.05-0.2 mg/dL 0.1
• Case 1: Decreased ALP - decreased food intake?
Liver Case ExamplesRef Value 1 2
ALT 30-55 IU/L 34 130
SDH 10-20 IU/L 16 13
ALP 250-350 IU/L 157 321
TBA 25-35 µmol/L 31 27
Tbili 0.1-0.5 mg/dL 0.2 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1
Liver Case ExamplesRef Value 1 2
ALT 30-55 IU/L 34 130
SDH 10-20 IU/L 16 13
ALP 250-350 IU/L 157 321
TBA 25-35 µmol/L 31 27
Tbili 0.1-0.5 mg/dL 0.2 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1
• Case 2: Increased ALT
Liver Case ExamplesRef Value 1 2
ALT 30-55 IU/L 34 130
SDH 10-20 IU/L 16 13
ALP 250-350 IU/L 157 321
TBA 25-35 µmol/L 31 27
Tbili 0.1-0.5 mg/dL 0.2 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1
• Case 2: Increased ALT - suspect enzyme induction
Liver Case ExamplesRef Value 1 2 3
ALT 30-55 IU/L 34 130 450
SDH 10-20 IU/L 16 13 63
ALP 250-350 IU/L 157 321 279
TBA 25-35 µmol/L 31 27 43
Tbili 0.1-0.5 mg/dL 0.2 0.3 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1 0.1
Liver Case ExamplesRef Value 1 2 3
ALT 30-55 IU/L 34 130 450
SDH 10-20 IU/L 16 13 63
ALP 250-350 IU/L 157 321 279
TBA 25-35 µmol/L 31 27 43
Tbili 0.1-0.5 mg/dL 0.2 0.3 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1 0.1
• Case 3: Increased ALT, SDH, TBA
Liver Case ExamplesRef Value 1 2 3
ALT 30-55 IU/L 34 130 450
SDH 10-20 IU/L 16 13 63
ALP 250-350 IU/L 157 321 279
TBA 25-35 µmol/L 31 27 43
Tbili 0.1-0.5 mg/dL 0.2 0.3 0.3
Dbili 0.05-0.2 mg/dL 0.1 0.1 0.1
• Case 3: Increased ALT, SDH, TBA - suspect hepatocellular injury
Liver Case ExamplesRef Value 4
ALT 30-55 IU/L 44
SDH 10-20 IU/L 18
ALP 250-350 IU/L 257
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 9.3
Dbili 0.05-0.2 mg/dL 0.3
Liver Case ExamplesRef Value 4
ALT 30-55 IU/L 44
SDH 10-20 IU/L 18
ALP 250-350 IU/L 257
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 9.3
Dbili 0.05-0.2 mg/dL 0.3
• Case 4: Increased Tbili
Liver Case ExamplesRef Value 4
ALT 30-55 IU/L 44
SDH 10-20 IU/L 18
ALP 250-350 IU/L 257
TBA 25-35 µmol/L 31
Tbili 0.1-0.5 mg/dL 9.3
Dbili 0.05-0.2 mg/dL 0.3
• Case 4: Increased Tbili - suspect hemolytic disease
Liver Case ExamplesRef Value 4 5
ALT 30-55 IU/L 44 51
SDH 10-20 IU/L 18 20
ALP 250-350 IU/L 257 301
TBA 25-35 µmol/L 31 13
Tbili 0.1-0.5 mg/dL 9.3 0.3
Dbili 0.05-0.2 mg/dL 0.3 0.1
Liver Case ExamplesRef Value 4 5
ALT 30-55 IU/L 44 51
SDH 10-20 IU/L 18 20
ALP 250-350 IU/L 257 301
TBA 25-35 µmol/L 31 13
Tbili 0.1-0.5 mg/dL 9.3 0.3
Dbili 0.05-0.2 mg/dL 0.3 0.1
• Case 5: Decreased TBA
Liver Case ExamplesRef Value 4 5
ALT 30-55 IU/L 44 51
SDH 10-20 IU/L 18 20
ALP 250-350 IU/L 257 301
TBA 25-35 µmol/L 31 13
Tbili 0.1-0.5 mg/dL 9.3 0.3
Dbili 0.05-0.2 mg/dL 0.3 0.1
• Case 5: Decreased TBA - suspect impaired enterohepatic recirculation
Liver Case ExamplesRef Value 4 5 6
ALT 30-55 IU/L 44 51 87
SDH 10-20 IU/L 18 20 28
ALP 250-350 IU/L 257 301 987
TBA 25-35 µmol/L 31 13 104
Tbili 0.1-0.5 mg/dL 9.3 0.3 4.7
Dbili 0.05-0.2 mg/dL 0.3 0.1 3.1
Liver Case ExamplesRef Value 4 5 6
ALT 30-55 IU/L 44 51 87
SDH 10-20 IU/L 18 20 28
ALP 250-350 IU/L 257 301 987
TBA 25-35 µmol/L 31 13 104
Tbili 0.1-0.5 mg/dL 9.3 0.3 4.7
Dbili 0.05-0.2 mg/dL 0.3 0.1 3.1
• Case 6: Increased ALT, SDH, ALP, TBA, T & Dbili
Liver Case ExamplesRef Value 4 5 6
ALT 30-55 IU/L 44 51 87
SDH 10-20 IU/L 18 20 28
ALP 250-350 IU/L 257 301 987
TBA 25-35 µmol/L 31 13 104
Tbili 0.1-0.5 mg/dL 9.3 0.3 4.7
Dbili 0.05-0.2 mg/dL 0.3 0.1 3.1
• Case 6: Increased ALT, SDH, ALP, TBA, T & Dbili - suspect biliary obstruction
Evaluation of KidneyNeed ~75% of nephrons non-functional for alterations in serum
markers to occurUrea Nitrogen (UN, BUN)
• Method of ammonia excretion• Liver converts ammonia to urea; kidney excretes urea• Sample stability - stabile serum and urine• Increased - renal and non-renal (e.g., dehydration) causes• Decreased - hepatic insufficiency
Creatinine (Cre, Creat)• Waste product of muscle metabolism• Excreted by kidney• Sample stability - stabile serum and urine• Increased - renal injury • Decreased - decreased muscle mass
Evaluation of Kidney - cont.Urine indicators
• Urine contains most constituents found in plasma (except molecules >70,000 daltons)
• But concentration varies due to water conserving ability of kidney• When interpreting data must account for kidney’s concentrating ability (per
time or per mg creatinine basis)• Sample stability - concentrated salt solution (some enzymes are not
stabile in urine)• Urine specific gravity - estimates concentrating ability; alterations when
66% of nephrons affected• Chemical constituents - creatinine, glucose, protein, ALP, LDH, AST,
NAG, glucuronidase, electrolytesWhen evaluating quantitative urine chemistry data, always normalize (e.g., creatinine, urine volume)
PGMBE Urinalysis: raw dataAnalyte Control 1200 ppmSG 1.017 1.013Volume (mL) 12.2 26.8Creat (mg/dL) 68.4 34.0Gluc (mg/dL) 8.0 5.0Prot (mg/dL) 65.0 54.0AST (IU/L) 6 26LDH (IU/L) 27 54NAG (IU/L) 10 9
Normalization Calculations
• Using creatinine• Assay Variable (units/vol.) / Creatinine (mg/dL)
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat or 117 g/mg
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat or 117 g/mg
• Urine LDH
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat or 117 g/mg
• Urine LDH• (27 U/L / 68.4 mg/dL) = 0.39 U LDH/mg creat
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat or 117 g/mg
• Urine LDH• (27 U/L / 68.4 mg/dL)/10 = 0.039 U LDH/mg creat
Creatinine Normalization Calculation
• Assay Variable (units/vol.) / Creatinine (mg/dL)
• Examples• Urine glucose
• 8.0 mg/dL / 68.4 mg/dL = 0.117 mg Glu/mg creat or 117 g/mg
• Urine LDH• (27 U/L / 68.4 mg/dL)/10 = 0.039 U LDH/mg creat or 39 mU/mg
PGMBE Urinalysis: converted dataAnalyte Control 1200 ppmGluc (ug/mg creat) 117 147Prot (ug/mg creat) 950 1588AST (mU/mg creat) 9 76LDH (mU/mg creat) 39 159NAG (mU/mg creat) 15 26
Normalization Calculations
• Using creatinine• Assay Variable (units/vol.) / creatinine (mg/dL)
• Using volume• Assay Variable (units/vol.) x volume (mL/time)
Urine constituent unit conversions for the 1-chloro-2-propanol study
Conversions were performed using treatment group mean values.
Tx. Grps. Body Wght. Ur. Vol. Ur. Gluc. Ur. Prot. Ur. Gluc. Ur. Prot. Ur. Gluc. Ur. Prot. ppm g mL/16 hr mg/dL mg/dL mg/16 hr mg/16 hr mg/100 g/16 hr mg/100 g/16 hr
Males (day 15):0 193 5.6 24 73 1.34 4.09 0.70 2.1233 191 8 23 62 1.84 4.96 0.96 2.60
100 198 6.6 22 60 1.45 3.96 0.73 2.00330 192 5 29 53 1.45 2.65 0.76 1.381000 189 4.5 33 63 1.49 2.84 0.79 1.503300 155 0.9 89 81 0.80 0.73 0.52 0.47
Males (Wk 13):0 383 5.9 31 68 1.83 4.01 0.48 1.0533 372 6.8 25 69 1.70 4.69 0.46 1.26
100 373 6.2 27 70 1.67 4.34 0.45 1.16330 378 5.6 29 81 1.62 4.54 0.43 1.201000 373 4.7 33 80 1.55 3.76 0.42 1.013300 312 2.7 73 95 1.97 2.57 0.63 0.82
Volume Normalization Calculation
• Assay Variable (units/vol.) x Volume (mL/time)
• Example• Urine glucose
• 24.0 mg/dL x 5.6 mL/16 hr x dL/100 mL = 1.34 mg Glu/16 hr
Urine constituent unit conversions for the 1-chloro-2-propanol study
Conversions were performed using treatment group mean values.
Tx. Grps. Body Wght. Ur. Vol. Ur. Gluc. Ur. Prot. Ur. Gluc. Ur. Prot. Ur. Gluc. Ur. Prot. ppm g mL/16 hr mg/dL mg/dL mg/16 hr mg/16 hr mg/100 g/16 hr mg/100 g/16 hr
Males (day 15):0 193 5.6 24 73 1.34 4.09 0.70 2.1233 191 8 23 62 1.84 4.96 0.96 2.60
100 198 6.6 22 60 1.45 3.96 0.73 2.00330 192 5 29 53 1.45 2.65 0.76 1.381000 189 4.5 33 63 1.49 2.84 0.79 1.503300 155 0.9 89 81 0.80 0.73 0.52 0.47
Males (Wk 13):0 383 5.9 31 68 1.83 4.01 0.48 1.0533 372 6.8 25 69 1.70 4.69 0.46 1.26
100 373 6.2 27 70 1.67 4.34 0.45 1.16330 378 5.6 29 81 1.62 4.54 0.43 1.201000 373 4.7 33 80 1.55 3.76 0.42 1.013300 312 2.7 73 95 1.97 2.57 0.63 0.82
Other MarkersProteins
• Total• Albumin• Globulin
Carbohydrate Metabolism • Glucose
Lipid Metabolism • Cholesterol• Triglycerides
Muscle• Creatine Kinase or Phosphokinase (CK, CPK) - total and isoenzymes• Troponin T and I
Other MarkersElectrolytes
• Sodium• Potassium• Chloride• Bicarbonate• Calcium• Phosphorus
Hormones • Insulin• Thyroxine (T4)• Triiodothyronine (T3)• Thyroid Stimulating Hormone (TSH)• Estradiol (E2)• Progesterone (P10)• Testosterone
0.000.00
0.250.25
0.500.50
0.750.75
1.001.00
00
55
1010
1515
2020
2525
Comparison of cTn Measurement in the Cynomolgus Comparison of cTn Measurement in the Cynomolgus MonkeyMonkey
cTn
I (n
g/m
L)
cTn
I (n
g/m
L)
cTn
T (
ng
/mL
)cT
nT
(n
g/m
L)
NegNeg LowLow MedMed HighHigh
Roche Elecsys 2010
Monkey Troponin EIA
DPC Immulite
OCD Vitros ECi
Dade Dimension RxL
Beckman Access
Bayer Advia Centaur
Tosoh AIA 600 II
Abbott Architect
ProteinuriaDetection of protein in urine (plasma,
genitourinary)In general:
>20 mg/kg/dayPersistent
TypesFunctional - reversible
• Stress• Exercise • Fever/exposure to temp extremes
• Seizures• Congestion of kidneys
Glomerular overload - HyperproteinemiaGlomerular - may result in hypoalbuminemiaTubular overload - Hgb, Mgb, Bence-JonesTubular - defective resorption
MethodsTougher to do in urine v. serum
• Small quantities• Sample-to-sample variation• Origin of protein• Protein degradation products
Sample: Fresh or refrigerated• Screening (dipstick) - uncentrifuged • Quantitative or semiquantitative - centrifuged
Methods - cont.Dipstick
• Screening - based on pH dyes• Albumin gives stronger results
Spectrophotometric• Quantitative - timed collection • Toluene• Ur prot/Ur creatinine ratios
SSATT - semiquantitativeBence Jones - heat precipitation
Reference ValuesDog
• <20mg/kg/day• 0.67 - 0.96 mg prot/mg creat
F344 rats (adult male)• ~141 mg/dL (67 - 213 mg/dL) • ~5.5 mg/16 hr• ~0.87 mg prot/mg creat (0.68 - 1.01 mg prot/mg creat)
F344 rats (adult female)• 10 mg/dL (7 - 16 mg/dL) • ~0.7 mg/16 hr• ~0.11 mg prot/mg creat (0.09 - 0.13 mg prot/mg creat)