40 - Cancer

Editors: McPhee, Stephen J.; Papadakis, Maxine A.; Tierney, Lawrence M.

Title: Current Medical Diagnosis & Treatment, 46th Edition

Copyright ©2007 McGraw-Hill

> Back of Book > Appendix

Appendix

Appendix: Therapeutic Drug Monitoring & Laboratory Reference Ranges

C. Diana Nicoll MD, PhD, MPA

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Table 1. Therapeutic drug monitoring.1

Drug Effective Concentrations Half-Life (hours) Dosage Adjustment Comments
Amikacin Peak: 20-30 mg/L; trough: < 10 mg/L 2-3 ↑ in uremia ↓ in renal dysfunction Concomitant kanamycin or tobramycin therapy may give falsely elevated amikacin results by immunoassay.
Amitriptyline 95-250 ng/mL 9-46   Drug is highly protein-bound. Patient-specific decrease in protein binding may invalidate quoted range of effective concentration.
Carbamazepine 4-12 mg/L 10-15   Induces its own metabolism.
Metabolite 10,11-epoxide exhibits 13% cross-reactivity by immunoassay. Toxicity: diplopia, drowsiness, nausea, vomiting, and ataxia.
Cyclosporine 100-300 mcg/L (ng/mL) whole blood 6-12 Need to know specimen and methodology used Cyclosporine is lipid-soluble (20% bound to leukocytes; 40% to erythrocytes; 40% in plasma, highly bound to lipoproteins). Binding is temperature-dependent, so whole blood is preferred to plasma or serum as specimen. High-performance liquid chromatography (HPLC) or monoclonal fluorescence polarization immunoassay measures cyclosporine reliably; polyclonal fluorescence polarization immunoassays cross-react with metabolites, so the therapeutic range used with those assays is higher. Anticonvulsants and rifampin increase metabolism. Erythromycin, ketoconazole, and calcium channel blockers decrease metabolism.
Desipramine 100-250 ng/mL 13-23   Drug is highly protein-bound. Patient-specific decrease in protein binding may invalidate quoted range of effective concentration.
Digoxin 0.8-2 ng/mL 42; ↑ in uremia, CHF ↓ in renal dysfunction, CHF, hypothyroidism ↑ in hyperthyroidism Bioavailability of digoxin tablets is 50-90%.
Specimen must not be drawn within 6 hours of dose.
Dialysis does not remove a significant amount.
Hypokalemia potentiates toxicity.
Digitalis toxicity is a clinical and not a laboratory diagnosis.
Digibind (digoxin-specific antibody) therapy of digoxin overdose can interfere with measurement of digoxin levels depending on the digoxin assay.
Elimination reduced by quinidine, verapamil, and amiodarone.
Ethosuximide 40-100 mg/L Child: 30
Adult: 50
  Levels used primarily to assess compliance. Toxicity is rare and does not correlate well with plasma concentrations.
Gentamicin Peak: 4-8 mg/L; trough: < 2 mg/L 2-5 ↑ in uremia (7.3 on dialysis) ↓ in renal dysfunction Draw peak specimen 30 minutes after end of infusion.
Draw trough just before next dose.
In uremic patients, carbenicillin may decrease gentamicin half-life from 46 hours to 22 hours.
Imipramine 180-350 ng/mL 10-16   Drug is highly protein-bound. Patient-specific decrease in protein binding may invalidate quoted range of effective concentration.
Lidocaine 1-5 mg/L 1.8 ↔ in uremia, CHF; ↑ in cirrhosis ↓ in CHF, liver disease Levels increased with cimetidine therapy.
Central nervous system toxicity common in the elderly.
Lithium 0.7-1.5 mmol/L 22 ↑ in uremia ↓ in renal dysfunction Thiazides and loop diuretics may increase serum lithium levels.
Methotrexate   8.4 ↑ in uremia ↓ in renal dysfunction 7-Hydroxymethotrexate cross-reacts 1.5% in immunoassay.
To minimize toxicity, leucovorin should be continued if methotrexate level is > 0.1 mcmol/L at 48 hours after start of therapy. Methotrexate > 1 mcmol/L at > 48 hours requires an increase in leucovorin rescue therapy.
Nortriptyline 50-140 ng/mL 18-44   Drug is highly protein-bound. Patient-specific decrease in protein binding may invalidate quoted range of effective concentration.
Phenobarbital 10-40 mg/L 86 ↑ in cirrhosis ↓ in liver disease Metabolized primarily by the hepatic microsomal enzyme system.
Many drug-drug interactions.
Phenytoin 10-20 mg/L; 5-10 mg/L in uremia, hypoalbuminemia Dose-dependent   Metabolite cross-reacts 10% in immunoassay.
Metabolism is capacity-limited. Increase dose cautiously when level approaches therapeutic range, since new steady-state level may be disproportionately higher.
Drug is very highly protein-bound; protein binding is decreased in uremia and hypoalbuminemia.
Primidone 5-10 mg/L 8   Phenobarbital cross-reacts 0.5%.
Metabolized to phenobarbital.
Primidone/phenobarbital ratio > 1:2 suggests poor compliance.
Procainamide 4-8 mg/L 3 ↑ in uremia ↓ in renal dysfunction 30% of patients with plasma levels of 12-16 mcg/mL have electrocardiographic changes; 40% of patients with plasma levels of > 16 mcg/mL have severe toxicity.
Metabolite N-acetylprocainamide is active.
Quinidine 1-4 mg/L 7↔ in CHF; ↑ in liver disease ↓ in liver disease, CHF Effective concentration is lower in chronic liver disease and nephrosis, where binding is decreased.
Salicylate 150-300 mg/L Dose-dependent    
Theophylline 5-20 mg/L 9 ↓ in CHF, cirrhosis, and with cimetidine Caffeine cross-reacts 10%.
Elimination is increased 1.5-2 times in smokers.1,3-Dimethyl uric acid metabolite increased in uremia and, because of cross-reactivity, may cause an apparent slight increase in serum theophylline.
Tobramycin Peak: 5-10 mg/L; trough: < 2 mg/L 2-3 ↑ in uremia ↓ in renal dysfunction Tobramycin, kanamycin, and amikacin may cross-react in immunoassay.
Valproic acid 55-100 mg/L 13-19   95% protein-bound.
Decreased binding in uremia and cirrhosis.
Vancomycin Trough: 5-15 mg/L 6 ↑ in uremia ↓ in renal dysfunction Toxicity in uremic patients leads to irreversible deafness. Keep peak level < 30-40 mg/L to avoid toxicity.
1Use red-topped tube (not marbled) for therapeutic drug monitoring. In general, the specimen should be drawn just before the next dose (trough).
× = unchanged; ↑ = increase(d); ↓ = decrease(d); CHF = congestive heart failure.
Modified and reproduced, with permission, from Nicoll D et al: Pocket Guide to Diagnostic Tests, 4th ed. McGraw-Hill, 2004.

Table 2. Reference ranges for commonly used tests.1,2

Current metric units × Conversion factor = SI units
SI units ÷ Conversion factor = Current metric units
Test Specimen Conventional Units Conversion Factor SI Units2 Collection
Acetaminophen Serum 10-20 mg/L
Panic: > 50 mg/L
66.16 66-132 mcmol/L Serum separator tube (SST)
Acetoacetate Serum or urine Negative   Negative SST or urine container
Adrenocorticotropic hormone (ACTH) Plasma 9-52 pg/mL (laboratory-specific) 0.22 2-11 pmol/L Siliconized glass or plastic lavender
Alanine aminotransferase (ALT, SGPT, GPT) Serum 7-56 units/L (laboratory-specific) 0.02 0.14-1.12 mckat/L (laboratory-specific) SST
Albumin Serum 3.4-4.7 g/dL 10.00 34-47 g/L SST
Aldosterone Serum Salt-loaded (120 mEq Na+/d): 27.74   SST
   Supine: 3-10 ng/dL 83-277 pmol/L
   Upright: 5-30 ng/dL 139-831 pmol/L
Salt-depleted (20 mEq Na+/d):  
   Supine: 12-36 ng/dL 332-997 pmol/L
   Upright: 17-137 ng/dL 471-3795 pmol/L
Urine Salt-loaded (120 mEq Na+/d for 3-4 days): 1.5-12.5 mcg/24 h 2.77 4.2-34.6 nmol/d Boric acid
Salt-depleted (20 mEq Na+/d for 3-4 days): 18-85 mcg/24 h 49.9-235.5 nmol/d
Alkaline phosphatase Serum 41-133 units/L (method- and age-dependent) 0.02 0.7-2.2 mckat/L (method- and age-dependent) SST
Ammonia (NH3) Plasma 18-60 mcg/dL 0.59 11-35 mcmol/L Green (iced)
Amylase Serum 20-110 units/L (laboratory-specific) 0.02 0.33-1.83 mckat/L (laboratory-specific) SST
Angiotensin-converting enzyme (ACE) Serum 12-35 units/L (method-dependent) 16.67 < 590 nkat/L (method-dependent) SST
Antithrombin III (AT III) Plasma 84-123% (qualitative)22-39 mg/dL (quantitative)     Blue
α1-Antitrypsin Serum 110-270 mg/dL 0.01 1.1-2.7 g/L SST
Aspartate aminotransferase (AST, SGOT, GOT) Serum 0-35 units/L (laboratory-specific) 0.02 0-0.58 mckat/L (laboratory-specific) SST
Basophil count Whole blood 0.01-0.12 × 103/mcL 1.00 0.01-0.12 × 109/L Lavender
Bilirubin Serum Total: 0.1-1.2 mg/dL
Direct (conjugated to glucuronide): 0.1-0.5 mg/dL
Indirect (unconjugated): 0.1-0.7 mg/dL
17.10 2-21 mcmol/L
< 8 mcmol/L
< 12 mcmol/L
SST
Blood urea nitrogen (BUN) Serum 8-20 mg/dL 0.36 2.9-7.1 mmol/L SST
β-Natriuretic peptide Whole blood < 50 pg/mL     Lavender
C-peptide Serum 0.8-4.0 ng/mL 1.00 0.8-4.0 mcg/L Iced (fasting)
Gold SST
C-reactive protein Serum < 5 mg/L 1.00 < 5 mg/L SST
Calcitonin Plasma Male: 0-11.5 pg/mL
Female: 0-4.6 pg/mL
1.00 Male: 0-11.5 ng/L
Female: 0-4.6 ng/L
Green Gold SST
Calcium (Ca2+) Serum 8.5-10.5 mg/dL
Panic: < 6.5 or > 13.5 mg/dL
0.25 2.1-2.6 mmol/L SST
Calcium (ionized) Serum 4.6-5.3 mg/dL 0.25 1.15-1.32 mmol/L Green (anaerobic)
Calcium (UCa) Urine 100-300 mg/d 0.025 2.5-7.5 mmol/d Urine bottle containing hydrochloric acid
Carbon dioxide, partial pressure (Pco2) Whole blood 32-48 mm Hg 0.13 4.26-6.38 kPa Heparinized syringe (iced)
Carbon dioxide (CO2), total (bicarbonate) Serum 22-32 mEq/L
Panic: < 15 or > 40 mEq/L
1.00 22-32 mmol/L
Panic: < 15 or > 40 mmol/L
SST
Carboxyhemoglobin (HbCO) Whole blood < 9% of total hemoglobin (Hb) 0.01 < 0.09 fraction of total hemoglobin Green
Carcinoembryonic antigen (CEA) Serum 0-5 ng/mL 1.00 0-5 mcg/L SST
CD4 T cell count Whole blood 359-1725 cells/mcL     Lavender (complete blood count and differential and % CD4 required)
Ceruloplasmin Serum 20-60 mg/dL (laboratory-specific) 10.00 200-600 mg/L SST
Chloride (Cl-) Serum 101-112 mEq/L 1.00 101-112 mmol/L SST
Cholesterol Serum Desirable: < 200 mg/dL
Borderline: 200-239 mg/dL
High risk: > 240 mg/dL
0.03 Desirable: < 5.2 mmol/L
Borderline: 5.2-6.1 mmol/L
High risk: > 6.2 mmol/L
SST
Chorionic gonadotropin, β-subunit (β-hCG), quantitative Serum Males and nonpregnant females: undetectable or < 5 mU/mL 1.00 Males and nonpregnant females: undetectable or < 5 units/L SST
Complement C3 Serum 64-166 mg/dL 10.00 640-1660 mg/L SST
Complement C4 Serum 15-45 mg/dL 10.00 150-450 mg/L SST
Complement CH50 Serum (Laboratory-specific)     Red
Cortisol Serum 8:00 AM: 5-20 mcg/dL 27.59 140-550 nmol/L SST
Cortisol (urinary free) Urine 10-110 mcg/24 h 2.76 30-300 nmol/d Urine bottle containing boric acid
Creatine kinase (CK) Serum 32-267 units/L (method-dependent) 0.02 0.53-4.45 mckat/L (method-dependent) SST
Creatine kinase MB (CKMB) Serum < 16 units/L or < 4% of total CK (laboratory-specific)
Mass units: 0-7 mcg/L
0.04 < 0.27 mckat/L SST
Creatinine (Cr) Serum 0.6-1.2 mg/dL 83.3 50-100 mcmol/L SST
Creatinine clearance (ClCr) See Collection column. Adults: 90-140 mL/min/1.73 m2 body surface area (BSA) 0.017 1.5-2.3 mL/s/1.73 m2 BSA Carefully timed 24-hour urine and simultaneous serum or plasma creatinine sample
Cryoglobulins Serum < 0.12 mg/dL     Red (at 37 °C)
Eosinophil count Whole blood 0.04-0.5 × 103/mcL 1.00 0.04-0.5 × 109/L Lavender
Erythrocyte count (RBC count) Whole blood 4.7-6.1 × 106/mcL 1.00 4.7-6.1 × 1012/L Lavender
Erythrocyte sedimentation rate Whole blood Male: < 10 mm/h
Female: < 15 mm/h (laboratory-specific)
  Same Lavender
Erythropoietin (EPO) Serum 5-20 mU/mL 1.00 5-20 units/L SST
Ethanol Serum mg/dL
Legal “driving under the influence” in many states is defined as > 80 mg/dL (> 17 mmol/L) blood alcohol level; serum alcohol levels are 10-35% higher than blood alcohol levels
0.217 mmol/L SST
Factor VIII assay Plasma 40-150% of normal (varies with age)     Blue
Fecal fat Stool Random: < 60 droplets of fat per high-power field72-hour: < 7 g/d     Qualitative: Random stool sample
Quantitative: 72-hour collection following 2-day dietary fat regimen
Ferritin Serum Male: 16-300 ng/mL
Female: 4-161 ng/mL
1.00 Male: 16-300 mcg/L
Female: 4-161 mcg/L
SST
α-Fetoprotein (AFP) Serum 0-15 ng/mL 1.00 0-15 mcg/L SST
Fibrin D-dimers Plasma Negative     Blue
Fibrinogen (functional) Plasma 175-433 mg/dL
Panic: < 75 mg/dL
0.01 1.75-4.3 g/L Blue
Folic acid (red cells) Whole blood 165-760 ng/mL 2.27 370-1720 nmol/L Lavender
Follicle-stimulating hormone (FSH) Serum Female: 1.00 Female: SST
Follicular phase 4-13 mU/mL 4-13 units/L
Luteal phase 2-13 mU/mL 2-13 units/L
Midcycle 5-22 mU/mL 5-22 units/L
Postmenopausal 30-138 mU/mL 30-138 units/L
Male: 1-10 mU/mL (laboratory-specific) Male: 1-10 units/L (laboratory-specific)
Free erythrocyte protoporphyrin (FEP) Whole blood < 35 mcg/dL (method-dependent)     Lavender
Fructosamine Serum     190-270 mcmol/L SST
γ-Glutamyltranspeptidase (GGT) Serum 9-85 units/L (laboratory-specific) 0.02 0.15-1.42 mckat/L (laboratory-specific) SST
Gastrin Serum < 100 pg/mL (laboratory-specific) 1.00 < 100 ng/L SST
Glucose Serum 60-110 mg/dL
Panic: < 40 or > 500 mg/dL
0.055 3.3-6.1 mmol/L (Fasting) SST
Glucose-6-phosphate dehydrogenase (G6PD) screen Whole blood 5-14 units/g Hb 0.02 0.1-0.28 mckat/L Lavender
Glutamine Cerebrospinal fluid (CSF) 6-15 mg/dL
Panic: > 40 mg/dL
68.5 411-1028 mcmol/L Collect CSF in a plastic tube
Glycated (glycosylated) hemoglobin (HbA1c) Serum 3.9-6.9% (method-dependent)     Lavender
Growth hormone (GH) Serum 0-5 ng/mL 1.00 0-5 mcg/L SST
Haptoglobin Serum 46-316 mg/dL 0.01 0.5-3.2 g/L SST
HDL cholesterol Serum Male: 27-67 mg/dL
Female: 34-88 mg/dL
0.026 0.7-1.73 mmol/L0.88-2.28 mmol/L SST
Helicobacter pylori antibody Serum Negative     SST
Hematocrit (Hct) Whole blood Male: 39-49%
Female: 35-45% (age-dependent)
0.01 Male: 0.39-0.49
Female: 0.35-0.45
Lavender
Hemoglobin A1c (See Glycated Hemoglobin) Serum        
Hemoglobin A2 (HbA2) Whole blood 1.5-3.5% of total hemoglobin 0.01 0.015-0.035 Lavender
Hemoglobin electrophoresis Whole blood HbA: > 95%
HbA2: 1.5-3.5%
    Lavender
Hemoglobin, fetal (HbF) Whole blood Adult: < 2% (varies with age)     Lavender
Hemoglobin, total (Hb) Whole blood Male: 13.6-17.5 g/dL
Female: 12.0-15.5 g/dL
Panic: ≤ 7 g/dL (age-dependent)
10.00 Male: 136-175 g/L
Female: 120-155 g/L
Lavender
Hemosiderin Urine Negative     Urine container
HIV viral load Plasma Negative     Lavender
Homocysteine Plasma 4-12 mcmol/L 1.00 4-12 mcmol/L Lavender
5-Hydroxyindoleacetic acid (5-HIAA) Urine 2-8 mg/24 h 5.23 10-40 mcmol/d Urine bottle containing hydrochloric acid
IgG index Serum and CSF 0.29-0.59 ratio     SST and plastic tube for CSF
Immunoglobulins (Ig) Serum IgA: 78-367 mg/dL
IgG: 583-1761 mg/dL
IgM: 52-335 mg/dL
0.01 IgA: 0.78-3.67 g/L
IgG: 5.83-17.6 g/L
IgM: 0.52-3.35 g/L
SST
Insulin, immunoreactive Serum 6-35 mcU/mL 7.18 42-243 pmol/L SST
Insulin-like growth factor-1 Plasma 123-463 ng/mL (age- and sex-dependent) 1.0 123-463 mcg/L SST
Iron (Fe2+) Serum 50-175 mcg/dL 0.18 9-31 mcmol/L SST
Iron-binding capacity, total (TIBC) Serum 250-460 mcg/dL 0.18 45-82 mcmol/L SST
Lactate dehydrogenase (LDH) Serum 88-230 units/L (laboratory-specific) 0.02 1.46-3.82 mckat/L (laboratory-specific) SST
Lactic acid (lactate) Venous blood 0.5-2.0 mEq/L 1.00 0.5-2.0 mmol/L Gray
LDL cholesterol Serum < 130 mg/dL 0.026 < 3.37 mmol/L SST
Lead (Pb) Whole blood Child: < 25 mcg/dL
Adult: < 40 mcg/dL
0.05 Child: < 1.21 mcmol/L
Adult: < 1.93 mcmol/L
Navy
Lecithin/sphingomyelin (L/S) ratio Amniotic fluid > 2.0 (method-dependent)     Collect in a plastic tube
Leukocyte alkaline phosphatase (LAP) Whole blood 40-130Based on 0 to 4+ rating of 100 polymorphonuclear neutrophils stained for alkaline phosphatase     Green
Leukocyte (white blood cell) count, total (WBC count) Whole blood 4.8-10.8 × 103/mcL
Panic: < 1.5 < 103/mcL
1.00 4.8-10.8 × 109/L Lavender
Lipase Serum 0-160 units/L (laboratory-specific) 0.02 0-2.66 mckat/L (laboratory-specific) SST
Luteinizing hormone (LH) Serum Female: 1.00   SST
Follicular phase 1-18 mU/mL 1-18 units/L
Luteal phase 0.4-20 mU/mL 0.4-20 units/L
Midcycle 24-105 mU/mL 24-105 units/L
Postmenopausal 15-62 mU/mL 15-62 units/L
Male: 1-10 mU/mL (laboratory-specific) Male: 1-10 units/L (laboratory-specific)
Lymphocyte count Whole blood 0.8-3.5 × 103/mcL 1.00 0.8-3.5 × 109/L Lavender
Magnesium (Mg2+) Serum 1.8-3.0 mg/dL
Panic: < 0.5 or > 4.5 mg/dL
0.41 0.75-1.25 mmol/L SST
Mean corpuscular hemoglobin (MCH) Whole blood 26-34 pg     Lavender
Mean corpuscular hemoglobin concentration (MCHC) Whole blood 31-36 g/dL 10.00 310-360 g/L Lavender
Mean corpuscular volume (MCV) Whole blood 80-100 fL     Lavender
Metanephrines Urine 0.3-0.9 mg/24 h 5.46 1.6-4.9 mcmol/d Urine bottle containing hydrochloric acid
Methemoglobin (MetHb) Whole blood < 1% of total hemoglobin 0.01 < 0.01 fraction of total hemoglobin Green
Methylmalonic acid Serum 0-0.05 mg/L 8.475 0-0.4 mcmol/L SST
Monocyte count Whole blood 0.2-0.8 × 103/mcL 1.00 0.2-0.8 × 109/L Lavender
Neutrophil count Whole blood 2.2-8.6 × 103/mcL 1.00 2.2-8.6 × 109/L Lavender
Osmolality Serum 275-293 mosm/kg H2O
Panic: < 240 or > 320 mosm/kg H2O
1.00 275-293 mmol/kg H2O SST
Urine Random: 100-900 mosm/kg H2O 1.00 Random: 100-900 mmol/kg H2O Urine container
Oxygen, partial pressure (Po2) Whole blood 83-108 mm Hg 0.13 11.04-14.36 kPa Heparinized syringe (iced)
Parathyroid hormone (PTH) Serum Intact PTH: 11-54 pg/mL (laboratory-specific) 0.11 Intact PTH: 1.2-5.7 pmol/L (laboratory-specific) Red
Partial thromboplastin time, activated (PTT) Plasma 25-35 seconds (range varies)
panic: ≥ 60 seconds
    Blue
pH Whole blood Arterial: 7.35-7.45Venous: 7.31-7.41     Heparinized syringe (iced)
Phosphorus Serum 2.5-4.5 mg/dL
panic: < 1.0 mg/dL
0.32 0.8-1.45 mmol/L SST
Platelet count (Plt) Whole blood 150-450 × 103/mcL
Panic: < 25 < 103/mcL
1.0 150-450 × 109/L
Panic: < 25 < 109/L
Lavender
Platelet-associated IgG Whole blood Negative     Lavender
Porphobilinogen (PBG) Urine Negative     Protect from light
Potassium (K+) Serum 3.5-5.0 mEq/L
panic: < 3.0 or > 6.0 mEq/L
1.00 3.5-5.0 mmol/L SST
Prolactin (PRL) Serum < 20 ng/mL 1.00 < 20 mcg/L SST
Prostate-specific antigen (PSA) Serum 0-4 ng/mL 1.00 0-4 mcg/L SST
Protein C Plasma 71-176%     Blue
Protein electrophoresis Serum Adults: Albumin: 3.3-4.7 g/dL
α1: 0.1-0.4 g/dL
α2: 0.3-0.9 g/dL
β2: 0.7-1.5 g/dL
γ: 0.5-1.4 g/dL
10.00
33-47 g/L1-4 g/L3-9 g/L7-15 g/L5-14 g/L
SST
Protein S (antigen) Plasma 76-178%     Blue
Protein, total Serum 6.0-8.0 g/dL 10.00 60-80 g/L SST
Prothrombin time (PT) Whole blood 11-15 seconds
panic: ≥ 30 seconds (laboratory-specific)
    Blue
Red blood cell count Whole blood 4.7-6.1 × 106/mcL 1.00 4.7-6.1 × 1012/L Lavender
Red cell volume Whole blood 25-35 mL/kg     Green
Renin activity (PRA) Plasma High-sodium diet (75-150 mEq Na+/d):
Supine: 0.2-2.3 ng/mL/h
Standing: 1.3-4.0 ng/mL/h)
Low-sodium diet (30-75 mEq Na+/d):
Standing: 4.0-7.7 ng/mL/h)
    Lavender
Reptilase clotting time Plasma 13-19 seconds     Blue
Reticulocyte count Whole blood 33-137 × 103/mcL 1.00 33-137 × 109/L Lavender
Russell's viper venom clotting time (dilute) (RVVT) Plasma 24-37 seconds     Blue
Salicylate (aspirin, others) Serum 20-30 mg/dL
panic: > 35 mg/dL
10.00 200-300 mg/L SST
Sodium (Na+) Serum 135-145 mEq/L
panic: < 125 or > 155 mEq/L
1.00 135-145 mmol/L SST
Testosterone Serum Male: 175-781 ng/dL
Female: 10-75 ng/dL
0.0347 Male: 6-27 nmol/L
Female: 0.3-2.6 nmol/L
SST
Thrombin time Plasma 8-12 seconds (laboratory-specific)     Blue
Thyroglobulin Serum 3-42 ng/mL 1.00 3-42 mcg/L SST
Thyroid-stimulating hormone (TSH) Serum 0.4-6 mcU/mL 1.00 0.4-6 mU/L SST
Thyroid-stimulating hormone receptor antibody (TSH-R Ab [stim]) Serum < 130% of basal activity; based on cAMP generation in thyroid cell tissue culture      
Thyroxine, free (FT4) Serum 9-24 pmol/L (varies with method)     SST
Thyroxine (T4), total Serum 5-11 mcg/dL 12.80 64-142 nmol/L SST
Thyroxine index, free (FT4I) Serum 6.5-12.5     SST
Transferrin Serum 190-375 mg/dL 0.01 1.9-3.75 g/L SST
Triglycerides Serum < 165 mg/dL 0.01 < 1.8 mmol/L SST (fasting)
Triiodothyronine (T3), total Serum 95-190 ng/dL 0.015 1.5-2.9 nmol/L SST
Troponin-I (cTnI) Serum < 0.05 ng/mL     SST
Uric acid Serum Male: 2.4-7.4 mg/dL
Female: 1.4-5.8 mg/dL
59.48 Male: 140-440 mcmol/L
Female: 80-350 mcmol/L
SST
Vanillylmandelic acid (VMA) Urine 2-7 mg/24 h 5.05 10-35 mcmol/d Urine bottle containing hydrochloric acid
Vitamin B12 Serum 140-820 pg/mL 0.74 100-600 pmol/L SST
Vitamin B12 absorption test (Schilling test) 24-hour urine Excretion of > 8% of administered dose     Urine bottle
Vitamin D, 25-hydroxy (25[OH]D) Serum 10-50 ng/mL 2.5 25-125 nmol/L SST
Vitamin D, 1,25-dihydroxy (1,25[OH]2D) Serum 20-76 pg/mL 2.4 48-182 pmol/L SST
White blood cell count Whole blood 4.8-10.8 × 103/mcL 1.00 4.8-10.8 × 109/L Lavender
1The reference ranges given here in conventional units and in SI units are from several large medical centers. Always use the reference ranges provided by your clinical laboratory, since ranges may be method-dependent.
2Reference: Young DS: Implementation of SI units for clinical laboratory data. Ann Intern Med 1987;106:114; JAMA Instructions for Authors, JAMA 1997;278:74.

Table 3. Commonly used specimen collection tubes.

Tube Tube Contents Typical Use
Lavender EDTA Complete blood count
SST Serum separator Serum chemistry tests
Red None Blood banking (serum); therapeutic drug monitoring
Blue Citrate Coagulation studies
Gray Inhibitor of glycolysis (sodium fluoride) Lactic acid
Green Heparin Plasma studies
Yellow Acid citrate HLA typing
Navy Trace metal free Trace metals (eg, lead)
EDTA = ethylenediaminetetraactic acid; SST = serum separator tube.