4 Diagnostic Laboratory Studies in the ICU Patient: What, When, and How Often?



10.1055/b-0038-160234

4 Diagnostic Laboratory Studies in the ICU Patient: What, When, and How Often?

John Ogunlade, Dan E. Miulli, and Jon Taveau


Abstract


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.





































Table 4.1 Common laboratory panels 1 , 2 , 3 , 4 , 5 , 6 , 7

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.










































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































Table 4.2 Normal laboratory values 1 , 2 , 3 , 4 , 5 , 6 , 7

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.

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