4 Diagnostic Laboratory Studies in the ICU Patient: What, When, and How Often?
John Ogunlade, Dan E. Miulli, and Jon TaveauAbstract
Diagnostic laboratory studies assist in excluding or confirming a diagnosis when combined with a thorough history and physical examination so that a treatment plan can ultimately be formulated and performed in a precise manner. Laboratory studies are not meant to be ordered indiscriminately but strictly and critically to unmask the underlying pathological process.
Case Presentation
An 18-year-old woman presents with acute onset of the worst headache of her life and decreased consciousness.
See end of chapter for Case Management.
4.1 Introduction
Diagnostic laboratory studies are tools used to enhance the overall clinical picture. They assist in excluding or confirming a diagnosis when combined with a thorough history and physical examination so that a treatment plan can ultimately be formulated and performed. Reassessing the patient and repeating diagnostic studies continue to confirm the diagnosis is accurate. This circular assessment sequence is the foundation of clinical medicine. It should be repeated as often as necessary.
In the intensive care unit (ICU) patient, every laboratory test order is critical to unmasking the underlying process, and proper use of every bit of information is imperative. Ordering multiple studies indiscriminately, the so-called shotgun approach, adds much confusion to the assessment as well as a terrible cost burden. By using a strict, sequenced, clinical approach to diagnosis, costs, mistakes, and misdiagnoses are lessened. ► Table 4.1 and ► Table 4.2 list common laboratory panels and normal laboratory values, respectively. This chapter serves to help streamline decision making in laboratory test selections and to better interpret the information provided by these tests.
Adrenal function Cortisol Dexamethasone suppression test (DST) Cosyntropin Metyrapone test and corticotropin (ACTH)–releasing hormone (CRH) Stimulation Dehydroepiandrosterone sulfate (DHEA-S) 17-ketosteroids 17-hydroxycorticosteroids |
Blood products Type and cross: blood group (ABO), type (Rh type), Rh cross-match Antibody Coombs’s antiglobulin (direct and indirect) HLA analysis Leukoagglutinin Platelet antibody |
Cardiac markers CK CK-MB Troponin (I, t) Homocysteine (Hcy) Myoglobin |
Coagulation PT INR Partial thromboplastin time, activated (aPTT) Bleeding time Platelet count |
Comprehensive metabolic panel (CMP) Sodium Potassium Chloride Carbon dioxide BUN Creatinine Glucose Calcium Magnesium Phosphorus Total protein Albumin Alkaline phosphatase ALT AST Bilirubin, total |
CSF analysis (routine) Color and clarity Gram stain C&S Cell count with differential (tubes 2 and 4) Protein Glucose |
CSF analysis (selective for infection) LDH Lactate Protein Immunoglobulin IgG–albumin index IgG, IgA, and IgM against Borrelia, parasites, and viruses Gram and Ziehl–Neelsen stain, touch prep Bacterial, fungal, viral, and mycobacterial culture DNA amplification (PCR) for tuberculosis and viral pathogens Syphilis (VDRL and FTA) Lyme disease Candida albicans |
CSF analysis (selective for cerebrovascular disease) Cystatin C Disseminated intravascular coagulopathy (DIC) PT INR Partial thromboplastin time, activated (aPTT) Bleeding time Platelet count D dimer Thrombin time (TT), thrombin clotting time Fibrin split products Protein C&S Antithrombin III Fibrinogen antithrombin (I) Coagulation factors Encephalopathy Folic acid Vitamin B12 TSH, T4 ammonia Creatinine Glutamine (CSF) |
Hemogram with differential (CBC) Hemoglobin Hematocrit Platelet count RBC count Red blood cell indices (MCV, MCH, MCHC) WBC count Absolute neutrophils, eosinophils, basophils, lymphocytes, and monocytes |
Hypercoagulable states Protein C Protein S Antithrombin III Factor V Leiden (activated protein C) Homocysteine Anticardiolipin antibodies Lupus anticoagulant |
Inflammation ESR CRP ANA Rheumatoid factor Uric acid |
Liver function Total protein Albumin Alkaline phosphatase ALT AST Bilirubin, total Ammonia (NH3) γ-glutamyltransferase (GGT) Prothrombin time (PT) Platelet count Serum protein electrophoresis |
Renal function CBC CMP 24-hour urine creatinine 24-hour urine protein Creatinine clearance |
Toxicology screen Acetaminophen Carbon monoxide Barbiturate Ethanol Ethylene glycol Cocaine Cyanide Benzodiazepines Tricyclic antidepressants Methanol Insulin |
Abbreviations: ACTH, adrenocorticotropic hormone; ALT, alanine aminotransferase; ANA, antinuclear antibody; AST, aspartate aminotransferase; BUN, blood urea nitrogen; CBC, complete blood count; CK, creatine kinase; CK-MB, creatine kinase–MB mass; CMP, cytidine monophosphate; CRP, C-reactive protein; CSF, cerebrospinal fluid; DNA, deoxyribonucleic acid; ESR, erythrocyte sedimentation rate; FTA, fluorescent treponemal antibody; HLA, human leukocyte antigen; Ig, immunoglobulin; INR, international normalized ratio; LDH, lactate dehydrogenase; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration; MCV, mean corpuscular volume; PCR, polymerase chain reaction; PT, prothrombin time; RBC, red blood cell; TSH, thyroid-stimulating hormone; VDRL, Venereal Disease Research Laboratory; WBC, white blood cell. |
Test | Specimen | Method | Normal range conventional units | SI units |
Acetylcholine receptor antibody | Serum | Immunoassay | < 0.5 nmol/L | < 0.5 nmol/L |
Acetylcholinesterase | RBC | Enzymatic colorimetry | 11,000–15,000 U/L | 11–15 kU/L |
Adrenocorticotropic hormone (ACTH) | Plasma | Immunoassay | < 70 μg/mL | < 15 pmol/L |
Alanine aminotransferase (ALT) | Serum | Enzymatic colorimetry | < 48 U/L | < 0.80 mkat/L |
Albumin | Serum | Colorimetry | 3.5–5.0 g/dL | 35–50 g/L |
Aldolase | Serum | Enzymatic colorimetry | < 8.1 U/L | < 135 nkat/L |
Aldosterone | Serum | Immunoassay | Supine: < 16 ng/dL Upright: 4–31 ng/dL | Supine: < 444 pmol/L Upright: 111–860 pmol/L |
Alkaline phosphatase Isoenzymes | Serum | Electrophoresis | Intestinal: < 18% of total activity Bone: 23–62% of total activity Liver: 38–72% of total activity | Intestinal: < 0.18 of total activity Bone: 0.23–0.62 of total activity Liver: 0.38–0.72 of total activity |
Total | Serum | Enzymatic colorimetry | 20–125 U/L | 0.33–2.08 mkat/L |
Ammonia | Plasma | Enzymatic colorimetry | 0.17–0.80 mg/mL | 10–47 μmol/L |
Amylase | Serum | Enzymatic colorimetry | 30–170 U/L | 0.50–2.83 mkat/L |
Androstenedione | Serum | Immunoassay | 65–270 ng/dL Postmenopausal: < 180 ng/dL | 2.3–9.4 nmol/L Postmenopausal: < 6.3 nmol/L |
Angiotensin-converting enzyme (ACE) | Serum | Enzymatic colorimetry | 8–52 U/L | 133–867 nkat/L |
Antidiuretic hormone (ADH) | Plasma | Extraction/immunoassay | < 2.2 μg/mL (serum Osm < 285 mOsm/kg) | 2.2–8.5 μg/mL (serum Osm > 290 mOsm/kg) |
< 2.2ng/L (serum Osm < 285 mOsm/kg) | 2.2–8.5 ng/L (serum Osm > 290 mOsm/kg) | |||
Anti-DNA antibody (double-stranded) | Serum | Immunoassay | < 30 U/mL | < 30 kU/L |
Antimicrosomal antibody (thyroid) | Serum | Immunoassay | < 0.3 U/mL | < 300 U/L |
Antimitochondrial antibody | Serum | Immunofluorescence | Negative (< 1:20) | |
Antineutrophil cytoplasmic antibody (ANCA) | Serum | Immunofluorescence | Negative (< 1:20) | |
Antinuclear antibody (ANA) | Serum | Immunofluorescence | Negative (< 1:40) | |
Antithrombin III activity | Plasma | Nephelometry | 85–130% of normal activity | 0.85–1.3 of normal activity |
Antithrombin III antigen | Plasma | Enzymatic colorimetry | 25–33 mg/dL | 250–330 mg/L |
Antithyroglobulin antibody | Serum | Immunoassay | < 1 U/mL | < 1 kU/L |
α1-antitrypsin | Serum | Nephelometry | 80–200 mg/dL | 0.8–2.0 g/L |
Apolipoprotein A-I | Serum | Nephelometry | Male: 94–176 mg/dL | Male: 0.94–1.76 g/L |
Female: 101–198 mg/dL | Female 1.01–1.98 g/L | |||
Apolipoprotein B | Serum | Nephelometry | Male: 52–109 mg/dL | Male: 0.52–1.09 g/L |
Female: 49–103 mg/dL | Female: 0.49–1.03 g/L | |||
Apolipoprotein E | Serum | Nephelometry | ||
Apolipoprotein E4 | Serum | Nephelometry | ||
Arsenic | Urine | ICP-MS | < 50 mg/d | < 0.65 mmol/day |
Aspartate aminotransferase (AST) | Serum | Enzymatic colorimetry | < 42 U/L | < 0.7 mkat/L |
Bilirubin | ||||
Direct | Serum | Colorimetry | < 0.4 mg/dL | < 7 mmol/L |
Indirect | Serum | Colorimetry | < 1.3 mg/dL | < 22 mmol/L |
Total | Serum | Colorimetry | < 1.3 mg/dL | < 22 mmol/L |
Bleeding time, template | Not applicable | Template method | 2.5–9.5 minutes | |
Cancer antigen (CA) 15.3 | Serum | ABBOTT AXSYM | < 32 U/mL | < 32 kU/L |
CA15–3MEIA | ||||
CA 19.9 | Serum | CIS ELSA-CA 19–9 IRMA | < 33 U/mL | < 33 kU/L |
CA 27.29 | Serum | BIOMIRA TRUQANT | < 38 U/mL | < 38kU/L |
BR RIA | ||||
CA 125 | Serum | CENTOCOR-CA125IIRIA | < 35 U/mL | < 35 kU/L |
Calcitonin | Serum | Immunoassay | Male: < 13.8 μg/mL | Male: < 13.8 ng/L |
Calcitonin | Serum | Immunoassay | Female: < 6.4 μg/mL | Female: < 6.4 ng/L |
Calcium | Serum | Colorimetry | 8.5–10.3 mg/dL | 2.12–2.57 mmol/L |
Urine | Colorimetry | Male: < 300 mg/d | Male: < 7.5 mmol/day | |
Female: < 250 mg/d | Female: < 6.2 mmol/d | |||
Carbon dioxide | Serum | Colorimetry | 20–32 mmol/L | 20–32 mmol/L |
Carboxyhemoglobin | Blood | Spectrophotometry | < 2% of total Hb (nonsmoker) | < 0.02 |
Carcinoembryonic antigen (CEA) | Serum | CHIRON ACS: 180 ICMA | < 2.5 ng/mL (nonsmoker) | < 2.5 mg/L (nonsmoker) |
Catecholamines Fractionated | Plasma | HPLC | Dopamine | Dopamine |
Supine: < 90 μg/mL | Supine: < 588 pmol/L | |||
Standing: < 90 μg/mL | Standing: < 588 pmol/L | |||
Epinephrine | Epinephrine | |||
Supine: < 50 μg/mL | Supine: < 273 pmol/L | |||
Standing: < 90 μg/mL | Standing: < 491 pmol/L | |||
Norepinephrine | Norepinephrine | |||
Supine: 110–410 μg/mL | Supine: 650–2423 pmol/L | |||
Standing: 125–700 μg/mL | Standing: 739–4137 pmol/L | |||
Total | Plasma | HPLC | Supine: 120–450 μg/mL | Supine: 709–2660 pmol/L |
Standing: 150–750 μg/mL | Standing: 887–4433 pmol/L | |||
Ceruloplasmin | Serum | Nephelometry | 25–63 mg/dL | 250–630 mg/L |
Chloride | Serum | ISE | 95–108 mmol/L | 95–108 mmol/L |
Cholesterol, total | Serum | Colorimetry | Desirable: < 200 mg/dL | Desirable: < 5.17 mmol/L |
Borderline-high: | Borderline-high: | |||
200–239 mg/dL | 5.17–6.18 mmol/L | |||
High: > 240 mg/dL | High: > 6.21 mmol/L | |||
Complement | ||||
C3 | Serum | Nephelometry | 75–161 mg/dL | 0.75–1.61 g/L |
C4 | Serum | Nephelometry | 16–47 mg/dL | 0.16–0.47 g/L |
Total (CH 50) | Serum | Liposome lysis | 31–66 U/mL | 31–66kU/L |
Complete blood count (CBC) | Blood | Automated analyzer | ||
Hemoglobin (Hb) | Male: 13.8–17.2 g/dL | Male: 138–172 g/L | ||
Female: 12.0–15.6 g/dL | Female: 120–156 g/L | |||
Hematocrit (Hct) | Male: 41–50% | Male: 0.41–0.50 | ||
Female: 35–46% | Female: 0.35–0.46 | |||
RBC count | Male: 4.4–5.8 × 106/mL | Male: 4.4–5.8 × 1012/L | ||
Female: 3.9–5.2 × 106/mL | Female: 3.9–5.2 × 1012/L | |||
RBC indices | Mean corpuscular volume: 78–102 fL | Mean corpuscular volume: 78–102 fL | ||
Mean corpuscular Hb: 27–33 μg | Mean corpuscular Hb: 27–33 μg | |||
Mean corpuscular Hb concentration: 32–36 g/dL | Mean corpuscular Hb concentration: 320–360 g/L | |||
RBC distribution width: < 15% | RBC distribution width: < 0.15 | |||
WBC count | 3.8–10.8 × 103/μL | 3.8–10.8 × 109/L | ||
WBC differential | Absolute neutrophils: 1,500–7,800 cells/mL | Absolute neutrophils: 1.5–7.8 × 109/L | ||
Absolute eosinophils: 50–550 cells/mL | Absolute eosinophils: 0.05–0.55 × 109/L | |||
Absolute basophils: 0–200 cells/mL | Absolute basophils: 0–0.2 × 109/L | |||
Absolute lymphocytes: 850–4100 cells/mL | Absolute lymphocytes: 0.85–4.10 × 109/L | |||
Absolute monocytes: 200–1100 cells/mL | Absolute monocytes: 0.2–1.109/L | |||
Platelet count | 130–400 × 103/mL | 130–400 × 109/L | ||
Cortisol, free | Urine | Immunoassay | 20–90 mg/d | 55–248 nmol/d |
Cortisol | Serum | Immunoassay | 4–22 mg/dL (morning specimen) | 110–607 nmol/L (morning specimen) |
3–17 mg/dL (afternoon specimen) | 83–469 nmol/L (afternoon specimen) | |||
C-peptide | Serum | Immunoassay | 0.8–4.0 ng/mL | 0.26–1.32 nmol/L |
C-reactive protein (CRP), creatine kinase (CK) | Serum | Nephelometry | < 0.8 mg/dL | < 8 mg/L |
Isoenzymes | Serum | Electrophoresis | CK-MM: 97–100% of total | CK-MM: 0.97–1.00 of total |
CK-MB: < 3% of total | CK-MB: < 0.03 of total | |||
CK-BB: 0% of total | CK-BB: 0 of total | |||
Total | Serum | Enzymatic colorimetry | Male: < 235 U/L | Male: < 3.92 mkat/L |
Female: < 190 U/L | Female: < 3.17 mkat/L | |||
Creatinine | Serum | Enzymatic colorimetry | < 1.2 mg/dL | < 106 mmol/L |
Urine | Enzymatic colorimetry | Male: 0.8–2.4 g/d | Male: 7.1–21.2 mmol/day | |
Female: 0.6–1.8 g/d | Female: 5.3–15.9 mmol/d | |||
Creatinine clearance | Serum, urine | Calculation: | Male: 82–125 mL/min | Male: 1.37–2.08 mL/s |
Female: 75–115 mL/min | Female: 1.25–1.92 mL/s | |||
Cyanide | Blood | Colorimetry | < 0.1 mg/L | < 3.8 mmol/L |
D-dimer | Plasma | Slide latex agglutination | < 250 mg/L | < 250 mg/L |
Dehydroepiandrosterone (DHEA), unconjugated | Serum | Immunoassay | 130–1200 ng/dL | 4.5–41.6 nmol/L |
Dehydroepiandrosterone sulfate (DHEA-S) | Serum | Immunoassay | Male (age): 29 years 1.4–7.9 mg/mL | Male (age): 29 years 3.8–21.4 mmol/L |
30–39 years 1.0–7.0 mg/mL | 30–39 years 2.7–19.0 mmol/L | |||
40–49 years 0.9–5.7 mg/mL | 40–49 years 2.4–15.5 mmol/L | |||
50–59 years 0.6–4.1 mg/mL | 50–59 years 1.6–11.1 mmol/L | |||
60–69 years 0.4–3.2 mg/mL | 60–69 years 1.1–8.7 mmol/L | |||
70–79 years 0.3–2.6 mg/mL | 70–79 years 0.8–7.1 mmol/L | |||
Female (age): | Female (age): | |||
29 years 0.7–4.5 mg/mL | 29 years 1.9–12.2 mmol/L | |||
30–39 years 0.5–4.1 mg/mL | 30–39 years 1.4–11.1 mmol/L | |||
40–49 years 0.4–3.5 mg/mL | 40–49 years 1.1–9.5 mmol/L | |||
50–59 years 0.3–2.7 mg/mL | 50–59 years 0.8–7.3 mmol/L | |||
60–69 years 0.2–1.8 mg/mL | 60–69 years 0.5–4.9 mmol/L | |||
70–79 years 0.1–0.9 mg/mL | 70–79 years 0.3–2.4 mmol/L | |||
11-deoxycortisol | Serum | Immunoassay | < 0.8 μg/dL | < 23 nmol/L |
Erythrocyte sedimentation rate (ESR) | Blood | Modified Westergren | Male: < 20 mm/h | Male: < 20 mm/h |
Female: < 30 mm/h | Female: < 30 mm/h | |||
Erythropoietin | Serum | Immunoassay | < 25 U/L | < 25 U/L |
Estradiol | Serum | Immunoassay | Male: < 50 μg/mL | Male: < 184 pmol/L |
Female: | Female: | |||
Follicular phase 10–200 μg/mL | Follicular phase 37–734 pmol/L | |||
Midcycle 100–400 μg/mL | Midcycle 367–1468 pmol/L | |||
Luteal phase 15–250 μg/mL | Luteal phase 55–954 pmol/L | |||
Postmenopausal < 50 μg/mL | Postmenopausal < 184 pmol/L | |||
Estrone | Serum | Immunoassay | Male: 29–81 μg/mL | Male: 107–300 pmol/L |
Female: | Female: | |||
Follicular phase 37–152 μg/mL | Follicular phase 137–562 pmol/L | |||
Midcycle 72–200 μg/mL | Midcycle 266–740 pmol/L | |||
Luteal phase 49–114 μg/mL | Luteal phase 181–422 pmol/L | |||
Postmenopausal < 65 μg/mL (without HRT) | Postmenopausal < 240 pmol/L (without HRT) | |||
Fatty acids, free | Plasma | Enzymatic colorimetry | 0.19–0.90 mEq/L | 0.19–0.90 mmol/L |
Ferritin | Serum | Immunoassay | Male: 18–350 ng/mL | Male: 18–350 mg/L |
Female (age): | Female (age): | |||
15–49 years 12–156 ng/mL | 15–49 years 12–156 mg/L | |||
> 49 years 18–204 ng/mL | > 49 years 18–204 mg/L | |||
Fibrinogen | Plasma | Photo-optical clot detection | 200–400 mg/dL | 2–4 g/L |
Folic acid | RBC | Immunoassay | > 95 ng/mL | > 215 nmol/L |
Serum | Immunoassay | > 1.9 ng/mL | > 4.3 nmol/L | |
Follicle-stimulating hormone (FSH) | Serum | Immunoassay | Male (age): 20–70 years: 0.9–15.0 U/L | Male (age): 20–70 years: 0.9–15.0 U/L |
> 70 years: 2.8–55.5 U/L | > 70 years: 2.8–55.5 U/L | |||
Female: follicular phase 1.1–9.6 U/L | Female: Follicular phase 1.1–9.6 U/L | |||
Midcycle 2.3–20.9 U/L | Midcycle 2.3–20.9 U/L | |||
Luteal phase 0.8–7.5 U/L | Luteal phase 0.8–7.5 U/L | |||
Pregnancy < 0.9 U/L | Pregnancy < 0.9 U/L | |||
Postmenopausal | Postmenopausal | |||
34.4–95.8 U/L | 34.4–95.8 U/L | |||
Free erythrocyte protoporphyrin (FEP) | Blood | Fluorometry | < 35 mg/dL RBGs | < 0.62 mmol/L RBGs |
Fructosamine | Serum | Colorimetry | 1.6–2.6 mmol/L | 1.6–2.6 mmol/L |
Gastrin | Serum | Immunoassay | < 200 μg/mL (nonfasting) | < 200 ng/L (nonfasting) |
< 100 μg/mL (fasting) | < 100 ng/L (fasting) | |||
Glucagon | Plasma | Immunoassay | 50–200 μg/mL | 50–200 ng/L |
Glucose | ||||
Fasting | Plasma | Enzymatic colorimetry | < 110 mg/dL | < 6.1 mmol/L |
Random | Serum | Enzymatic colorimetry | 70–125 mg/dL | 3.9–6.9 mmol/L |
Glucose-6-phosphate dehydrogenase (G6PD) | Blood | Enzymatic colorimetry | 5–13 U/g Hb | 5–13 U/g Hb |
γ-glutamyl transferase (GGT) | Serum | Enzymatic colorimetry | Male: < 65 U/L | Male: < 1.08 mkat/L |
Female: < 45 U/L | Female: < 0.75 mkat/L | |||
Growth hormone (GH) | Serum | Immunoassay | < 8 ng/mL | < 8 mg/L |
Haptoglobin | Serum | Nephelometry | 43–212 mg/dL | 0.43–2.12 g/L |
Hematocrit (Hct) | Blood | Automated analyzer | Male: 41–50% | Male: 0.41–0.50 |
Female: 35–46% | Female: 0.35–0.46 | |||
Hemoglobin (Hb) A1c | Blood | Automated analyzer | Male: 13.8–17.2 g/dL | Male: 138–172 g/L |
Female: 12.0–15.6 g/dL | Female: 120–156 g/L | |||
Blood | HPLC | < 6.0% of total Hb | < 0.06 of total Hb | |
Electrophoresis | Blood | Electrophoresis | Hb A1: < 96.0% | Hb A1: < 0.96 |
Hb A2: 1.5–3.5% | Hb A2: 0.015–0.035 | |||
Hb C: 0% | Hb C: 0 | |||
Hb F: < 2.0% | Hb F: < 0.02 | |||
Hb S: 0% | Hb S: 0 | |||
High-density lipoprotein (HDL) cholesterol | Serum | Precipitation/colorimetry | > 35 mg/dL | > 0.9 mmol/L |
“Negative” risk factor: > 60 mg/dL | “Negative” risk factor: > 1.55 mmol/L | |||
Homocysteine | Plasma | HPLC | 6.1–17.0 mmol/L | 6.1–17.0 mmol/L |
Homovanillic acid | Urine | HPLC | < 10 mg/d | < 55 mmol/d |
Human chorionic gonadotropin (hCG) | ||||
Qualitative | Urine | Immunoassay | Nonpregnant: negative | |
Pregnant: positive | ||||
Quantitative (intact and free b) | Serum | Immunoassay | Male: < 2 U/L | Male: < 2 U/L |
Female: | Female: | |||
Premenopausal: < 5 U/L | Premenopausal: < 5 U/L | |||
Postmenopausal: < 10 U/L | Postmenopausal: < 10 U/L | |||
Pregnancy: | Pregnancy: | |||
0–2 wk < 500 U/L | 0–2 wk < 500 U/L | |||
2–3 wk 100–5,000 U/L | 2–3 wk 100–5000 U/L | |||
3–4 wk 500–10,000 U/L | 3–4 wk 500–10,000 U/L | |||
1–2 months 1,000–200,000 U/L | 1–2 months 1000–200,000 U/L | |||
2–3 months | 2–3 months | |||
10,000–100,000 U/L | 10,000–100,000 U/L | |||
17-hydroxycorticosteroids | Urine | Enzymatic colorimetry | Male: 3–15 mg/d | Male: 8.3–41.4 mmol/d |
Female: 2–12 mg/d | Female: 5.5–33.1 mmol/d | |||
5-hydroxyindoleacetic acid (5-HIAA) | Urine | HPLC | 0.5–9.0 mg/d | 3–47 mmol/d |
Immunoglobulin | ||||
IgA | Serum | Nephelometry | 81–463 mg/dL | 0.81–4.63 g/L |
IgD | Serum | Radial immunodiffusion | < 14 mg/dL | < 0.14 g/L |
IgE | Serum | Immunoassay | < 180 U/mL | < 432 mg/L |
IgG, subclasses | Serum | Nephelometry | Subclass IgG 1:450–900 mg/dL | Subclass IgG 1:4.5–9.0 g/L |
Subclass IgG 2: 180–530 mg/dL | Subclass IgG 2:1.8–5.3 g/L | |||
Subclass IgG 3:1380 mg/dL | Subclass IgG 3: 0.13–0.80 g/L | |||
Subclass IgG 4: 8–100 mg/dL | Subclass IgG 4: 0.08–1.00 g/L | |||
IgC, total | Serum | Nephelometry | 723–1685 mg/dL | 7.23–16.85 g/L |
IgM | Serum | Nephelometry | 48–271 mg/dL | 0.48–2.71 g/L |
Insulin | Serum | Immunoassay | 5–25 mU/mL | 36–179 pmol/L |
Iron | Serum | Colorimetry | 25–170 mg/dL | 4–30 mmol/L |
Iron-binding capacity | Serum | Colorimetry | 200–450 mg/dL | 36–81 mmol/L |
% saturation: 12–57% | % saturation: 0.12–0.57 | |||
17-ketogenic steroids | Urine | Colorimetry | Male: 5–23 mg/d | Male: 17–80 mmol/d |
17-ketosteroids, total | Female: 3–15 mg/d | Female: 10–52 mmol/d | ||
Urine | Colorimetry | Male: 9–22 mg/d | Male: 31–76 mmol/d | |
Lactate dehydrogenase (LD) | Female: 5–15 mg/d | Female: 17–52 mmol/d | ||
Isoenzymes | Serum | Electrophoresis | LD1: 20–36% of total | LD1: 0.20–0.36 of total |
LD2: 32–50% of total | LD2: 0.32–0.50 of total | |||
LD3: 15–25% of total | LD3: 0.15–0.25 of total | |||
LD4: 2–10% of total | LD4: 0.02–0.10 of total | |||
LD5: 3–13% of total | LD5: 0.03–0.13 of total | |||
Total | Serum | Enzymatic colorimetry | < 270 U/L | < 4.5 mkat/L |
Lactic acid | Plasma (venous) | Enzymatic colorimetry | 9–16 mg/dL | 1.0–1.8 mmol/L |
Lead | Blood | Atomic spectroscopy | < 25 mg/dL | < 1.21 mmol/L |
Lipase | Serum | Enzymatic colorimetry | 7–60 U/L | 0.12–1.00 mkat/L |
Low-density lipoprotein (LDL) cholesterol, direct | Serum | Immunoseparation | Desirable: < 130 mg/dL | Desirable: < 3.36 mmol/L |
Colorimetry | Borderline-high: 130–159 mg/dL | Borderline-high: 3.36–4.11 mmol/L | ||
High: > 160 mg/dL | High:> 4.14 mmol/L | |||
Luteinizing hormone (LH) | Serum | Immunoassay | Male (age): 20–70 years | Male (age): 20–70 |
1.3–12.9 U/L | years 1.3–12.9 U/L | |||
> 70 years 11.3–56.4 U/L | > 70 years 11.3–56.4 U/L | |||
Female: | Female: | |||
Follicular phase 0.8–25.8 U/L | Follicular phase 0.8–25.8 U/L | |||
Midcycle 25.0–57.3 U/L | Midcycle 25.0–57.3 U/L | |||
Luteal phase 0.8–27.1 U/L | Luteal phase 0.8–27.1 U/L | |||
Pregnancy < 1.4 U/L | Pregnancy < 1.4 U/L | |||
Lymphocyte surface markers (T cell) | Postmenopausal 5.0–52.3 U/L | Postmenopausal 5.0–52.3 U/L | ||
CD3 | Blood | Flow cytometry | Absolute: 840–3060 cells/mL | Absolute: 0.84–3.06 × 109 cells/L |
Percentage: 57–85% | Percentage: 0.57–0.85 (57–85%) | |||
CD4 | Blood | Flow cytometry | Absolute: 490–1740 cells/mL | Absolute: 0.49–1.74 × 109 cells/L |
Percentage: 30–61% | Percentage: 0.30–0.61 (30–61%) | |||
CD8 | Blood | Flow cytometry | Absolute: 180–1170 cells/mL | Absolute: 0.18–1.17 × 109 cells/L |
Percentage: 12–42% | Percentage: 0.12–0.42 (12–42%) | |||
Helper/suppressor (CD4/CD8) ratio | Blood | Flow cytometry | 0.86–5.00 | 0.86–5.00 |
Magnesium | Serum | Colorimetry | 0.6–1.0 mmol/L | 0.6–1.0 mmol/L |
Mercury metanephrines | Blood | Atomic spectroscopy | < 1 mg/dL | < 50 nmol/L |
Fractionated | Urine | HPLC | Metanephrine: < 0.4 mg/d | Metanephrine: < 2.2 mmol/d |
Normetanephrine: < 0.9 mg/d | Normetanephrine: < 4.9 mmol/d | |||
Total | Urine | HPLC | < 1.3 mg/d | < 7.1 mmol/d |
Methemoglobin | Blood | Spectrophotometry | < 2% of total Hb | < 0. 02 of total Hb |
β2-microglobulin | Serum | Immunoassay | < 3 mg/L | < 3 mg/L |
Muramidase (lysozyme) | Serum | Turbidimetry | 2.8–8. 0 mg/L | 0.20–0.56 mmol/L |
Myelin basic protein | CSF | Immunoassay | < 4 ng/mL | < 4 mg/L |
Myoglobin | Serum | Immunoassay | < 55 ng/mL | < 55 mg/L |
Nitrogen, total | Feces | Acid digestion/titrimetry | < 2 g/d | < 143 mmol/d |
Osmolality | Serum | Freezing point depression | 278–305 mOsm/kg | 278–305 mmol/kg |
Urine | Freezing point depression | 50–1200 mOsm/kg | 50–1,200 mmol/kg | |
Oxalate | Urine | Colorimetry | < 40 mg/d | < 456 mmol/d |
Parathyroid hormone (PTH), intact | Serum | Immunoassay | 11–54 μg/mL | 1.2–5.8 pmol/L |
Partial thromboplastin time, activated (aPTT) | Plasma | Photo-optical clot detection | 20–36 s | 20–36 s |
Phosphorus | Serum | Colorimetry | 2.5–4.5 mg/dL | 0.81–1.45 mmol/L |
Platelet count | Blood | Automated analyzer | 130–400 × 103/mL | 130–400 × 109/L |
Porphobilinogen | Urine | Column chromatography/spectrophotometry | < 2 mg/d | < 8.8 mmol/d |
Porphyrins, fractionated (protoporphyrin) | Feces | HPLC | Dicarboxyporphyrin < 1,830 mg/d | Dicarboxyporphyrin < 3.26 mmol/d |
(protoporphyrin) | ||||
Heptacarboxyporphyrin < 20 mg/d | ||||
Octacarboxyporphyrin < 80 mg/d | Octacarboxyporphyrin < 96 nmol/d | |||
(uroporphyrin) | (uroporphyrin) | |||
Tetracarboxyporphyrin | Tetracarboxyporphyrin | |||
< 640 mg/d | < 977 nmol/d | |||
(coproporphyrin) | (coproporphyrin) | |||
Potassium | Serum | ISE | 3.5–5.3 mmol/L | 3.5–5.3 mmol/L |
Prealbumin | Serum | Nephelometry | 18–45 mg/dL | 180–450 mg/L |
Progesterone | Serum | Immunoassay | Male: < 1.2 ng/mL | Male: < 3.8 nmol/L |
Female: | Female: | |||
Follicular phase < 1.4 ng/mL | Follicular phase < 4.5 nmol/L | |||
Luteal phase 2.5–28.0 ng/mL | Luteal phase 8.0–89.0 nmol/L | |||
Pregnancy | Pregnancy | |||
1st trimester | 1st trimester | |||
9.0–47.0 ng/mL | 28.6–149.5 nmol/L | |||
2nd trimester | 2nd trimester | |||
17.0–146.0 ng/mL | 54.1–464.3 nmol/L | |||
3rd trimester | 3rd trimester | |||
55.0–255.0 ng/mL | 174.9–810.9 nmol/L | |||
Postmenopausal < 0.7 ng/mL | Postmenopausal < 2.2 nmol/L | |||
Prolactin | Serum | Immunoassay | Male: 2–18 ng/mL | Male:2–18 mg/mL |
Female: | Female: | |||
Nonpregnant 3–30 ng/mL | Nonpregnant 3–30 mg/L | |||
Pregnant 10–209 ng/mL | Pregnant 10–209 mg/L | |||
Postmenopausal 2–20 ng/mL | Postmenopausal 2–20 mg/L | |||
Prostate-specific antigen (PSA) | Serum | Immunoassay | < 4 ng/mL (male) | < 4 mg/L (male) |
Protein, total | Serum | Colorimetry | 6.0–8.5 g/dL | 60–85 g/L |
Urine | Colorimetry | < 150 mg/d | < 150 mg/d | |
Protein C activity | Plasma | Photo-optical clot detection | 70–140% of normal | 0.7–1.4 of normal |
Protein C antigen | Plasma | Immunoassay | 70–140% of normal | 0.7–1.4 of normal |
Protein electrophoresis | Serum | Electrophoresis | Albumin: 3.5–5.5 g/dL | Albumin: 35–55 g/L |
α1-globulins: 0.1–0. 3 g/dL | α1-globulins: 1–3 g/L | |||
α2-globulins: 0.2–1.1 g/dL | α2-globulins: 2–11 g/L | |||
β-globulins: 0.5–1.2 g/dL | β-globulins: 5–12 g/L | |||
γ-globulins: 0.5–1.5 g/dL | γ-globulins: 5–15 g/L | |||
Protein S activity | Plasma | Photo-optical clot detection | Male: 70–150% of normal | Male: 0.7–1.5 of normal |
Female: 58–130% of normal | Female: 0.58–1.30 of normal | |||
Protein S antigen | Plasma | Immunoassay | Male: 70–140% of normal | Male: 0.7–1.4 of normal |
Female: 70–140% of normal | Female: 0.7–1.4 of normal | |||
Prothrombin time (PT) | Plasma | Photo-optical clot detection international normalized ratio (INR): 0.9–1.1 (patients not on anticoagulant therapy) | 10.0–12.5 s | 10. 0–12. 5 s |
Protoporphyrin | ||||
Free erythrocyte | Blood | Fluorometry | < 35 mg/dL RBCs | < 0.62 mmol/L RBCs |
Zinc | Blood | Fluorometry | < 70 mg/dL | < 700 mg/L |
Pyruvate | Blood | Enzymatic colorimetry | 0.3–0.9 mg/dL | 34–102 mmol/L |
Pyruvate kinase | Blood | Fluorometry | Enzyme activity detected | |
RBC count | Blood | Automated analyzer | Male: 4.4–5.8 × 106/mL | Male: 4. 4–5. 8 × 1012/L |
Female: 3.9–5.2 × 106/mL | Female: 3.9–5.2 × 1012/L | |||
RBC indices | Blood | Automated analyzer | Mean corpuscular volume: 78–102 fL | Mean corpuscular volume: 78–102 fL |
Mean corpuscular Hb: 27–33 μg | Mean corpuscular Hb: 27–33 μg | |||
Mean corpuscular Hb | Mean corpuscular Hb | |||
concentration: 32–36 g/dL | concentration: 320–360 g/L | |||
RBC distribution width: < 15% | RBC distribution width: < 0.15 | |||
Renin activity | Plasma | Immunoassay | 1.3–4.0 ng/mL/h (upright) | 1.00–3. 07 nmol/L/h (upright) |
(Normal sodium intake: 100–200 mEq/d) | (Normal sodium intake: 100–200 mmol/d) | |||
Reticulocyte count | Blood | Automated analyzer | 0.5–2.3% of RBCs | 0.005–0.023 of RBCs |
Rheumatoid factor | Serum | Nephelometry | < 40 U/mL | < 40 kU/L |
Schilling test | Urine | Radio-isotopic measurement | > 7% of administered dose in 24-hour urine | > 0.07 of administered dose in 24-hour urine |
Scleroderma antibody (Scl-70) | -70) Serum | Immunoassay | Negative | |
Serotonin | Blood | HPLC | 46–319 ng/mL | 0.26–1.81 mmol/L |
Sodium | Serum | ISE | 135–146 mmol/L | 135–146 mmol/L |
Somatomedin-C | Serum | Immunoassay | Male: 90–318 ng/mL | Male: 90–318 mg/L |
Female: 116–270 ng/mL | Female: 116–270 mg/L | |||
T3 (triiodothyronine) Free | Serum | Immunoassay | 230–420 μg/dL | 3.5–6.5 pmol/L |
Reverse | Serum | Immunoassay | 2.6–18.9 ng/dL | 0.04–0. 29 nmol/L |
Total T4 (thyroxine) | Serum | Immunoassay | 60–181 ng/dL | 0.9–2. 8 nmol/L |
Free | Serum | Immunoassay | 0.8–1.8 ng/dL | 10–23 pmol/L |
Total | Serum | Immunoassay | 4.5–12.5 mg/dL | 58–161 nmol/L |
Testosterone, total | Serum | Immunoassay | Male: 194–833 ng/dL | Male: 6.7–28.9 nmol/L |
Female: 62 ng/dL | Female: < 2.1 nmol/L | |||
Thrombin time | Plasma | Photo-optical clot detection | 10.0–13.5 s | 10.0–13.5 s |
Thyroglobulin | Serum | Immunoassay | < 60 ng/mL | < 60 mg/L |
Thyroid-stimulating hormone (TSH), ultrasensitive (third generation) | Serum | Immunoassay | 0.50–4.70 mU/mL | 0.50–4.70 mU/L |
Thyroxine-binding globulin (TBG) | Serum | Immunoassay | 16–34 mg/L | 16–34 mg/L |
Transferrin | Serum | Nephelometry | 188–341 mg/dL | 1.88–3.41 g/L |
Triglycerides | Serum | Enzymatic colorimetry | < 200 mg/dL | < 2.26 mmol/L |
Urea nitrogen, blood (BUN) | Serum | Colorimetry | 7–30 mg/dL | 2.5–10.7 mmol urea/L |
Uric acid | Serum | Enzymatic colorimetry | Male: 4.0–8.5 mg/dL | Male: 238–506 mmol/L |
Female: 2.5–7.5 mg/dL | Female: 149–446 mmol/L | |||
Urine | Enzymatic colorimetry | 200–750 mg/d | 1.2–4.5 mmol/d | |
Urinalysis, complete | Urine | Reagent-impregnated strips | Appearance: clear, yellow | |
Microscopy | Specific gravity: 1.001–1.035 | |||
pH: 4.6–8.0 | ||||
Protein: negative | ||||
Glucose: negative | ||||
Reducing substances: negative | ||||
Ketones: negative | ||||
Bilirubin: negative | ||||
Occult blood: negative | ||||
WBC esterase: negative | ||||
Nitrite: negative | ||||
WBC: < 5/high-power field | ||||
RBC: < 3/high-power field | ||||
Renal epithelial cells: < 3/high-power field | ||||
Squamous epithelial cells: none or few/high-power field | ||||
Casts: none | ||||
Bacteria: none | ||||
Yeast: none | ||||
Vanillylmandelic acid (VMA) | Urine | HPLC | < 10 mg/d | < 50 mmol/d |
Viscosity | Serum | Viscometer | 1.5–1.9 viscosity units (relative to water) | |
Vitamin A | Serum | HPLC | 30–95 mg/dL | 1.05–3.32 mmol/L |
Vitamin B6 | Plasma | HPLC | 5–24 ng/mL | 30–144 nmol/L |
Vitamin B12 | Serum | Immunoassay | 200–800 μg/mL | > 150–590 pmol/L |
Vitamin C | Plasma | Colorimetry | 0.2–2.0 mg/dL | 11–114 mmol/L |
1,25-dihydroxy-vitamin D | Serum | Chromatography | 24–65 μg/mL | 58–156 pmol/L |
25-hydroxy-vitamin D | Serum | Acetonitrile extraction/immunoassay | 10–55 ng/mL | 25–137 nmol/L |
Vitamin E | Serum | Fluorometry | 5–20 mg/mL | 12–46 mmol/L |
WBC count | Blood | Automated analyzer | 3.8–10.8 × 103/mL | 3.8–10.8 × 109/L |
WBC differential | Blood | Automated analyzer | Absolute neutrophils: 1,500–7,800 cells/mL | Absolute neutrophils: 1.5–7.8 × 109/L |
Absolute eosinophils: 50–550 cells/mL | Absolute eosinophils: 0.05–0.55 × 109/L | |||
Absolute basophils: 0–200 cells/mL | Absolute basophils: 0–0.2 × 109/L | |||
Absolute lymphocytes: 850–4100 cells/mL | Absolute lymphocytes: 0.85–4.10 × 109/L | |||
Absolute monocytes: 200–1100 cells/mL | Absolute monocytes: 0.2–1.109/L | |||
Zinc | Plasma | Atomic spectroscopy | 60–130 mg/dL | 9.2–19.9 mmol/L |
Abbreviations: CSF, cerebrospinal fluid; DNA, deoxyribonucleic acid; HPLC, high-performance liquid chromatography; HRT, hormone replacement therapy; ICMA, immunochemiluminometric assay; ICP-MS, inductively coupled mass spectroscopy; IRMA, immunoradiometric assay; ISE, ion-selective electrode; MEIA, microparticle enzyme immunoassay; RBC, red blood (cell) count; RIA, radioimmunoassay; SI, International System of Units; WBC, white blood (cell) count. |