The WBC count and differential are a routine part of the complete blood count (CBC) test.
Basophils are granulocytes whose function is not fully understood. They are capable of ingesting foreign particles and secreting histamine. Basophils are associated with mast cells, express IgE and play a role in allergic inflammatory disease and anaphylaxis.
- Leukocytes or WBCs are differentiated into 5 different types:
- Basophils
- Eosinophils
- Lymphocytes
- Monocytes
- Neutrophils
The basophil count is only rarely of significant clinical utility. These cells are associated with mast cells, express IgE and play a role in allergic inflammatory disease and anaphylaxis.
The White Blood Cell (WBC) count and differential, which the basophil count is part of, has clinical utility in:
- Evaluation of infection or inflammation
- Assist in determination of viral versus bacterial infection
- Assist in evaluation of the stage and severity of an infection
- Detect allergic response or parasitic infections (elevated eosinophils)
- Evaluation for hematologic malignancy/disorders
- Detecting and identifying various types of myelopoietic disorders
- Detecting and identifying various types of leukemia
- Evaluating bone marrow depression
- Evaluation of need for further tests, such as manual WBC differential or bone marrow biopsy
- Evaluation of drug effects, response to chemotherapy or radiation
- Evaluation of effect of cytotoxic agents
- Screening test as part of a CBC on admission to a health care facility or before surgery
Additional information:
- The interpretation of a normal, high or low result of any given WBC type requires the context of the patient's clinical condition, history and physical examination
- Specific patterns of leukocyte response are seen in various types of diseases as determined by the differential count
- The life span of leukocytes is normally 13–20 days, after which the cells are destroyed in the lymphatic system and are excreted from the body in fecal matter.
Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.
WBC Differential
| Conv. Units
(%) | SI Units
(fraction) |
|---|
| Birth | 0-1 | 0-0.01 |
| 2-8 weeks | 0-1 | 0-0.01 |
| 2-6 months | 0-1 | 0-0.01 |
| 7-12 months | 0-1 | 0-0.01 |
| 1-5 years | 0-1 | 0-0.01 |
| 6-17 years | 0-1 | 0-0.01 |
| Adults | 0-1 | 0-0.01 |
Conditions, which may cause basophilia (increased basophils), include:
- Chronic hypersensitivity reactions
- Drugs
- Desipramine
- Paroxetine
- Tretinoin
- Triazolam
- Venlafaxine
- Food
- Inhalants
- Infections
- Sinusitis (Chronic)
- Varicella
- Inflammatory conditions
- Airway inflammation (Chronic)
- Dermatitis (Chronic)
- Inflammatory bowel disease
- Mast cell disease – urticaria pigmentosa
- Myeloproliferative disorders
- Basophilic leukemia
- Chronic granulocytic leukemia
- Chronic myelogenous leukemia
- Hodgkin's disease
- Myelofibrosis
- Polycythemia vera
- Others
- Chronic hemolytic anemia
- Hypothyroidism
- Myxedema
- Post-splenectomy
Drugs causing decrease in basophils include:
- Corticosteroids
- Procainamide
- Thiopental
Other conditions:
- Acute inflammation
- Hyperthyroidism