Blood Tests*

Test

Reference Range or Threshold (Conventional Units)

Acidity (pH)

7.35–7.45

Alcohol (ethanol)

0 mg/dL (more than 0.1 mg/dL usually indicates intoxication)

Ammonia

15–50 units/L

Amylase

53–123 units/L

Antinuclear antibodies (ANA)

0 (negative result)

0.4–1.5 mg/dL

Bicarbonate (carbon dioxide content)

18–23 mEq/L

Bilirubin

Direct: Up to 0.4 mg/dL

Total: Up to 1.0 mg/dL

Blood volume

8.5–9.1% of body weight

Calcium

8.5–10.5 mg/dL (slightly higher in children)

Carbon dioxide pressure (expressed as a comparison with how high the level of mercury [Hg] rises in a tube due to air pressure at sea level)

35–45 mm Hg

Carboxyhemoglobin (carbon monoxide in hemoglobin)

Less than 5% of total hemoglobin

CD4 cell count

500–1500 cells/μL

Ceruloplasmin

15–60 mg/dL

Chloride

98–106 mEq/L

Complete blood cell count (CBC)

See individual tests: Hemoglobin, hematocrit, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, platelet count, and white blood cell count

70–150 μg/dL

Creatine kinase (CK), also called creatine phosphokinase (CPK)

Male: 38–174 units/L

Female: 96–140 units/L

Creatine kinase (CK) in its different forms (isoenzymes)

5% or less of CK-MB (the form that occurs mainly in heart muscle)

Creatinine

0.6–1.2 mg/dL

Electrolytes

See individual tests: Calcium, chloride, magnesium, potassium, and sodium (which are routinely tested)

Erythrocyte sedimentation rate (ESR)

Male: 1–13 mm/hour

Female: 1–20 mm/hour

Glucose

Fasting: 70–110 mg/dL

Hematocrit

Male: 45–52%

Female: 37–48%

Hemoglobin

Male: 13–18 g/dL

Female: 12–16 g/dL

Iron

60–160 μg/dL (higher in males)

Iron-binding capacity

250–460 μg/dL

Lactate (lactic acid)

Venous: 4.5–19.8 mg/dL

Arterial: 4.5–14.4 mg/dL

Lactic dehydrogenase

50–150 units/L

Lead

20 μg/dL or less (much lower in children)

Lipase

10–150 units/L

Lipids:

Cholesterol, total

Less than 225 mg/dL (for age 40–49 yr; increases with age)

High-density lipoprotein (HDL)

30–70 mg/dL

Low-density lipoprotein (LDL)

60 mg/dL

Triglycerides

40–200 mg/dL (higher in males)

Liver function tests

Magnesium

1.5–2.0 mg/dL

Mean corpuscular hemoglobin (MCH)

27–32 pg/cell

Mean corpuscular hemoglobin concentration (MCHC)

32–36% hemoglobin/cell

Mean corpuscular volume (MCV)

76–100 cubic μm

Osmolality

280–296 mOsm/kg plasma

Oxygen pressure (expressed as a comparison with the level of mercury [Hg] in a tube, which results from air pressure at sea level)

83–100 mm Hg

Oxygen saturation (arterial)

96–100%

Partial thromboplastin time (PTT)

30–45 seconds

Phosphatase (alkaline)

50–160 units/L (higher in infants and adolescents, lower in females)

Phosphorus

3.0–4.5 mg/dL

Platelet count

150,000–350,000/mL

Potassium

3.5–5.0 mEq/L

Prostate-specific antigen (PSA)

0–4 ng/mL (increases with age)

Protein:

Total

6.0–8.4 g/dL

3.5–5.0 g/dL

Globulin

2.3–3.5 g/dL

Prothrombin time (PT)

10–13 seconds

Red blood cell (RBC) count

4.2–5.9 million/mL

Sodium

135–145 mEq/L

Thyroid-stimulating hormone (TSH)

0.5–5.0 m units/L

Transaminases (liver enzymes):

Alanine (ALT)

1–21 units/L

Aspartate (AST)

7–27 units/L

Troponin in its different forms:

I

Less than 1.6 ng/mL

T

Less than 0.1 ng/mL

7–18 mg/dL

Uric acid

3.0–7.0 mg/dL

§

30–65 μg/dL

White blood cell (WBC) count

4,300–10,800 /mL

*Blood can be tested for many other substances as well.

Units are explained in Appendix I. Conventional units can be converted to international units by using a conversion factor. International units (IU), a different system, are sometimes used by laboratories.

Other antibodies can also be identified.

§Other vitamins can also be measured.

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