Monocytes
Disclaimer: Information on this page is for educational purposes. Consult a physician to interpret your test results. Lissa Health helps track biomarker trends but does not replace medical advice.
What This Test Measures
Monocytes are large leukocytes that become tissue macrophages. They participate in chronic inflammation, phagocytosis, and antigen presentation to the immune system.
Monocytosis is characteristic of chronic infections (tuberculosis, endocarditis), recovery from acute inflammation, myeloproliferative disorders, and corticosteroid therapy.
Monocytopenia is rare and may indicate hairy cell leukemia or aplastic anemia.
Normal Ranges
| Group | Reference Range |
|---|---|
| Men | 2–8% (0.1–0.8 × 10⁹/L) |
| Women | 2–8% (0.1–0.8 × 10⁹/L) |
| Children | 2–10% |
Reference ranges may vary by laboratory and assay method.
Causes of High Levels
- Chronic infections (tuberculosis)
- Recovery from acute inflammation
- CMML, myeloproliferative neoplasms
- Autoimmune diseases
- Corticosteroids
Causes of Low Levels
- Aplastic anemia
- Hairy cell leukemia (characteristic finding)
- Chemotherapy
Test Preparation
- No preparation required
Related Biomarkers
| Biomarker | Relationship |
|---|---|
| White Blood Cells | Total leukocyte count |
| Erythrocyte Sedimentation Rate (ESR) | Chronic inflammation |
| C-Reactive Protein (CRP) | Acute vs chronic inflammation |
FAQ
How often should I take this test?
With CBC — annually; with chronic infections — as indicated.
What should I do if my result is abnormal?
Persistent monocytosis requires evaluation for chronic infection and hematologic disorders.
Last updated: June 2026