Skip to content

Myelocyte Count in Peripheral Blood

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

This test measures the number of immature white blood cells called myelocytes in your blood. These cells are part of your body’s immune system and help produce mature white blood cells.

Quick summary

["Knowing your myelocyte count can help doctors assess bone marrow function and blood health."]

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

Key facts at a glance

LOINC
17800-4
Short code
Myelocytes NFr Fld
Synonyms
Myelocytes 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

Why Is This Test Done?

Doctors may order a myelocyte count to evaluate conditions affecting blood production, such as infections, bone marrow disorders, or certain cancers. It can also help monitor treatment responses in patients undergoing chemotherapy or other blood-related therapies.

What Does a Myelocyte Count Tell You?

A myelocyte count helps identify whether your bone marrow is producing enough mature white blood cells. High counts might suggest overactive bone marrow, while low counts could indicate suppressed production due to illness or treatment side effects.

How Is This Test Performed?

This test involves drawing a small amount of blood from a vein, usually in your arm. The blood is then examined under a microscope to count the myelocytes present. No special preparation is needed, but fasting may not be required.

What Are Common Causes of Abnormal Results?

Elevated myelocyte counts may occur in conditions like leukemia, infections, or inflammatory diseases. Low counts could result from bone marrow disorders, chemotherapy, or severe infections that deplete white blood cells.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Myelocyte counts play a key role in diagnosing and managing blood disorders. For example, high counts may signal early leukemia or other hematologic malignancies, while low counts can indicate treatment-related suppression of blood cell production. Regular monitoring helps adjust therapies to maintain healthy blood cell levels.

Short name

Myelocyte Count

Frequently asked questions

What does a myelocyte count measure?
A myelocyte count measures the presence of immature white blood cells (myelocytes) in your bloodstream, which are precursors to mature white blood cells. This helps assess bone marrow function and overall blood health.
How often should I get this test?
The frequency depends on your medical condition. If you have a blood disorder, your doctor may recommend this test regularly to monitor changes. Otherwise, it’s usually done only when symptoms or other tests suggest it’s needed.
Can lifestyle changes affect myelocyte counts?
While diet and exercise generally don’t directly impact myelocyte counts, they can influence overall blood health. Avoiding smoking, managing stress, and staying hydrated may support healthy blood cell production, but this test specifically looks at myelocyte numbers in your blood sample.
  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