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Reference ranges for blood tests
Introduction
A reference range is a set of values used by a health professional to interpret a set of medical test results. The range is usually defined as the set of values 95% of the normal population falls within.
The reference range will vary, depending on the age, sex and race of a population, and even the instruments the laboratory uses to perform the tests. Furthermore, by definition, 5% of the normal population will fall outside the reference range.
Clinical biochemistry
Clinical biochemistry
- Items marked with a ** are part of “CHEM-7”[1] and CHEM-20
- Items marked with a * are part of “CHEM-20”[2], but not CHEM-7
| Category | Test | Low | High | Unit | Comments |
| Electrolytes and Metabolites[3] | ** Sodium (Na) | 136 | 145 | mmol/L | |
| ** Potassium (K) | 3.5 | 4.5 | mmol/L | ||
| Chloride (Cl) | 98 | 107 | μmol/L | ||
| Osmolality | 275 | 295 | mOsm/kg | ||
| Urea | 2.5 | 6.4 | mmol/L | ** BUN – blood urea nitrogen | |
| 7 | 18 | mg/dL | |||
| ** Creatinine – male | 62 | 115 | μmol/L | May be complemented with creatinine clearance | |
| 0.7 | 1.3 | mg/dL | |||
| ** Creatinine – female | 53 | 97 | μmol/L | ||
| 0.6 | 1.1 | mg/dL | |||
| ** Glucose (fasting) | 3.9 | 5.8 | mmol/L | See also glycosylated hemoglobin | |
| 70 | 105 | mg/dL | |||
| Acid base physiology See also: Arterial blood gas |
pH | 7.35 | 7.45 | ||
| base excess | -3 | +3 | |||
| PO2 | 10 | 13 | kPa | ||
| ** PCO2 | 4.8 | 5.8 | kPa | ||
| Bicarbonate (HCO3-) | 18 | 23 | mmol/L | ||
| Standard bicarbonate (SBCe) | 21 | 27 | mmol/L | ||
| Liver function tests | * Total Protein | 60 | 80 | g/L | |
| * Albumin | 35[4] | 50 | g/L | ||
| * Total Bilirubin | 2 | 14 | μmol/L | ||
| * Direct Bilirubin | 0 | 4 | μmol/L | ||
| * Alanine transaminase (ALT) | 8 | 40 | U/L | Also called serum glutamic pyruvic transaminase (SGPT) | |
| * Alkaline phosphatase (ALP) | 40 | 130 | U/L | Higher in children and pregnant women. | |
| * Gamma glutamyl transferase | n/a | 50 | U/L | ||
| Other enzymes and proteins | Creatine kinase (CK) – male | 24[5] | 195 | U/L | |
| Creatine kinase (CK) – female | 24[6] | 170 | U/L | ||
| * Aspartate transaminase (AST) | 8 | 35 | U/L | Also called serum glutamic oxatoacetic transaminase (SGOT) | |
| * Lactate dehydrogenase (LDH) | 85 | 285 | U/L | ||
| Amylase | n/a | 120[7] | U/L | ||
| C-reactive protein (CRP) | n/a | 5[8] | mg/L | ||
| D-dimer | n/a | 500 | ng/mL | ||
| Other ions and trace metals | Ionised calcium (Ca) | 1.15 | 1.29 | mmol/L | Some calcium is bound to albumin, thus not measured by certain techniques. |
| * Total calcium (Ca) | 2.05 | 2.55 | mmol/L | ||
| Phosphate (HPO42−) | 0.8 | 1.5 [9] | mM | ||
| Copper (Cu) | 11[10] | 24 | μmol/L | ||
| Zinc (Zn) | 10 | 17 | μmol/L | ||
| Blood lipids | Triglycerides | 0.4 | 2 | mmol/L | |
| * Total cholesterol | 3 | 5.0[11] | mmol/L | ||
| HDL cholesterol (male) | 0.7 | 1.9 | mmol/L | ||
| HDL cholesterol (female) | 0.9 | 2.4 | mmol/L | ||
| LDL cholesterol | 2.4 | 3[11] | mmol/L | Not valid when triglycerides >5.0 mmol/L. | |
| Tumour markers | Alpha fetoprotein (AFP) | n/a | 10 | kU/l | |
| Alpha 1-antitrypsin (AAT) | 20 | 53 | mmol/L | 150-350 mg/dL | |
| Beta Human chorionic gonadotrophin (bHCG) | n/a | 5 | IU/l | ||
| CA-125 (also CA12.5) | n/a | 35 | U/ml | ||
| CA15.3 | n/a | 28 | U/ml | ||
| CA19.9 | n/a | 40 | U/ml | ||
| Carcinoembryonic antigen (CEA) – non-smokers | n/a | 3 | μg/l | ||
| Carcinoembryonic antigen (CEA) – smokers | n/a | 5 | μg/l | ||
| Prostate specific antigen (PSA) | n/a | 4 | μg/L | ||
| Hormones | Thyroid stimulating hormone (TSH) | 0.3 | 3.0 | mIU/L | Also called: Thyrotropin |
| Free thyroxine (FT4) | 9 | 24 | pmol/L | ||
| Free triiodothyronine (FT3) | 2.5 | 5.3 | pmol/L | ||
| Adrenocorticotropic hormone (ACTH) | 1.3 | 15 | pmol/L | ||
| Cortisol (0830 h) | 250 | 850 | nmol/L | Cortisol levels are higher in the morning than at night. | |
| Cortisol (1630 h) | 110 | 390 | nmol/L | ||
| Prolactin (male) | n/a | 450 | mIU/L | ||
| Prolactin (female) | n/a | 580 | mIU/L | ||
| Testosterone (male) | 8 | 38 | nmol/L | ||
| Testosterone (male prepuberty) | 0.1 | 0.5 | nmol/L | ||
| Testosterone (female) | 0.3 | 2.5 | nmol/L |
- Not listed: * uric acid,
Hematology
Hematology
| Category | Test | Low | High | Unit | Comments |
| Red blood cells | Haemoglobin (Hb) (male) | 140 | 180 | g/L | Higher in neonates, lower in children. |
| Haemoglobin (Hb) (female) | 115 | 160 | g/L | Sex difference negligible until adulthood. | |
| Haematocrit (Hct) (male) | 0.38 | 0.52 | |||
| Haematocrit (Hct) (female) | 0.35 | 0.47 | |||
| Mean cell volume (MCV) | 80 | 98 | fL | Cells are larger in neonates, though smaller in other children. | |
| Mean cell haemoglobin (MCH) | 26 | 34 | pg | ||
| Red cell count (male) | 4.5 | 6.5 | x1012/L | ||
| Red cell count (female) | 3.8 | 5.8 | x1012/L | ||
| Reticulocytes | 10 | 100 | x109/L | ||
| White blood cells | Total white blood cells | 4 | 11 | x109/L | Higher in neonates and infants. |
| Neutrophil granulocytes | 2 | 7.5 | x109/L | 45-74%. Also known as granulocytes (grans), polys, PMNs, or segs. | |
| Lymphocytes | 1.3 | 4 | x109/L | 16-45% | |
| Monocytes | 0.2 | 0.8 | x109/L | 4.0-10% | |
| Eosinophil granulocytes | 0.04 | 0.4 | x109/L | 0.0-7.0% | |
| Basophil granulocytes | 0.01 | 0.1 | x109/L | 0.0-2.0% | |
| Coagulation | Platelets | 150 | 400 | x109/L | |
| Prothrombin time (PT)[12] | 11 | 13.5 | s | PT reference varies between laboratory kits – INR is standardised | |
| INR | 0.9 | 1.2 | The INR is a corrected ratio of a patients PT to normal | ||
| Activated partial thromboplastin time (APTT) | 29 | 41 | s | ||
| Thrombin clotting time (TCT) | 11 | 18 | s | ||
| Fibrinogen | 1.8 | 4 | g/L | ||
| Bleeding time | 2 | 9 | minutes |
Immunology
Immunology
| Category | Test | Low | High | Unit | Comments |
| Acute phase protein markers of Inflammation | Erythrocyte sedimentation rate (ESR) | 0 | 23 | mm/hr | Females tend to have a higher ESR. ESR increases with age.[13] |
| C-reactive protein (CRP) | 0 | 6 | mg/L | ||
| Autoantibodies | Antinuclear antibodies (ANA) | ||||
| Extractable nuclear antigen (ENA) | |||||
| Rheumatoid factor (RF) | 0 | 20 | IU/mL | High levels not specific for Rheumatoid Arthritis alone. | |
| Serology | Antistreptolysin O titre (ASOT) – preschoolers | n/a | 100 | units/mL | |
| Antistreptolysin O titre (ASOT) – others | n/a | 200 | units/mL |
See also
See also
References
References
- ↑ MedlinePlus Encyclopedia 003462
- ↑ MedlinePlus Encyclopedia 003468
- ↑ C. A. Burtis and E. R. Ashwood, Tietz Textbook of Clinical Chemistry (1994) 2nd edition, ISBN 0-7216-4472-4
- ↑ Template:GPnotebook
- ↑ Template:GPnotebook
- ↑ Template:GPnotebook
- ↑ Template:GPnotebook
- ↑ Template:GPnotebook
- ↑ Walter F., PhD. Boron. Medical Physiology: A Cellular And Molecular Approaoch. Elsevier/Saunders. ISBN 1-4160-2328-3. Page 849
- ↑ Template:GPnotebook
- ↑ 11.0 11.1 Template:GPnotebook
- ↑ MedlinePlus Encyclopedia 003652
- ↑ A formula for expected ESR values is age÷2 for males and (age+10)÷2 for females
External links
External links
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]