Skip to content

Monocyte Count in Blood (Absolute)

Published: August 9, 2026Updated: August 16, 2026

This test measures the number of monocytes, a type of white blood cell that helps your body fight infections and inflammation.

Quick summary

["Monocytes help protect your immune system by responding to infections and damaged tissues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
26487-9
Short code
Monocytes NFr Fld
Synonyms
Monocytes NFr Fld
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
86430
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What Are Monocytes?

Monocytes are a type of white blood cell produced in your bone marrow. They circulate in your bloodstream and move into tissues to help fight infections, repair damaged cells, and regulate inflammation. Your body produces monocytes in response to signals from other immune cells or when your body detects harmful substances.

Why Might You Need This Test?

Doctors may order a monocyte count test to assess immune function, diagnose or monitor conditions like infections, inflammatory diseases (such as rheumatoid arthritis), or certain blood disorders. It can also help evaluate responses to treatments.

How Is the Test Performed?

A small sample of your blood is drawn from a vein, usually in your arm. The sample is then analyzed in a lab to count the number of monocytes present in your blood.

What Do the Results Mean?

Results are typically reported as the absolute number of monocytes per microliter (µL) of blood. While reference ranges vary by lab, elevated or low monocyte counts may signal underlying health concerns that need further evaluation.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Monocyte Count

Frequently asked questions

How often do I need this test?
A monocyte count test is often performed as part of a routine blood panel or when symptoms suggest an immune or inflammatory issue. Your doctor will determine if repeat testing is needed based on your health status and test results.
What causes a high or low monocyte count?
High monocyte counts (monocytosis) can occur with chronic infections, certain cancers, or inflammatory diseases. Low monocyte counts (monocytopenia) may result from immune suppression, certain medications, or severe infections.
Can I prepare for this test?
No special preparation is usually required. Avoid heavy meals before the test, as this may slightly affect blood test results. If you are on medications, let your healthcare provider know before the test.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy