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Cytological examination of cells (specimen: whole blood)

Published: August 9, 2026Updated: August 15, 2026

This test checks the types and numbers of cells in your blood, including red blood cells, white blood cells, and platelets, to help identify potential health concerns.

Quick summary

["This test helps doctors monitor blood health and detect abnormalities early."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 15, 2026Editorial policy

Key facts at a glance

LOINC
32512-6
Short code
CD2ABS
Synonyms
CD2 Cells # Spec
Category
chemistry
Sample
serum
Container
EDTA (lavender-top) tube preferred; sodium heparin (green-top) tube acceptable for flow cytometry
Units
N/A
Ref low
700
Ref high
1500
Critical range
200 N/A – —
Fasting
false
Population
adult
Sex
all
Age range
≥ 0 years
Method
Flow cytometry using fluorescently labeled monoclonal antibodies against CD2 surface marker, with absolute counting via BD Trucount or equivalent bead-based methodology
CPT
86360
SNOMED
1428001000000101
Specimen volume
3-5 mL whole blood (minimum 1 mL for pediatric samples)
Stability
Whole blood stable at room temperature (20-25°C) for up to 24 hours; do not refrigerate or freeze as this may cause cell loss. Process within 24 hours of collection for optimal results.
Hemolysis max
100
Lipemia max
500
Icterus max
40
TAT
4–24 hours
Order
routine

What Does This Test Measure?

Your blood sample is analyzed to count and identify different cell types. Red blood cells carry oxygen, white blood cells fight infections, and platelets help with clotting. The test may also check for abnormal cell shapes or numbers that could signal conditions like anemia, infections, or blood disorders.

Why Might You Need This Test?

Doctors order this test to diagnose or monitor conditions such as infections, anemia, blood cancers, or other blood-related disorders. It’s also used before surgeries, during pregnancy, or if you have symptoms like fatigue, easy bruising, or frequent infections.

How Is the Test Performed?

A small blood sample is drawn from a vein, usually in your arm. The sample is then sent to a lab where it’s examined under a microscope to count and analyze the cells.

What Are Common Results?

Results typically include counts for red blood cells, white blood cells (with subtypes), and platelets, along with descriptions of cell appearance. Abnormal counts or cell types may trigger further testing.

Reference range

Absolute CD2+ T-cell counts vary by age; adult reference range approximately 700-1500 cells/μL (cells per microliter); pediatric values are higher and decline with age to adult levels. Results should be interpreted alongside complete lymphocyte subset panel (CD3, CD4, CD8, CD19, CD16/56).N/A

Specimen: serum

No fasting required. Patient should be well-hydrated. Recent vaccinations, active infections, or immunosuppressive therapy may affect results and should be documented. Avoid strenuous exercise prior to collection.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

This test is critical for diagnosing and managing blood disorders. Low red blood cell counts (anemia) may indicate iron deficiency or other issues, while high or low white blood cell counts could signal infections or immune problems. Platelet counts help assess bleeding risks or clotting disorders. Early detection through this test can guide treatment and prevent complications.

Short name

Blood Cell Count Screening

Frequently asked questions

What Does a High or Low White Blood Cell Count Mean?
A high white blood cell count may suggest an infection, inflammation, or a blood disorder like leukemia. A low count could mean your body isn’t making enough white blood cells, which may be due to immune system issues, chemotherapy, or other medications.
How Often Should I Get This Test?
Your doctor will determine how often you need this test based on your health history, symptoms, and treatment plan. Regular check-ups or follow-ups may include this test if you have a chronic condition like diabetes or heart disease.
Can I Eat or Drink Before the Test?
You can usually eat and drink normally before this test unless your doctor specifies otherwise. However, avoid heavy meals or alcohol just before the blood draw to ensure accurate results.
  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 15, 2026. · Read our editorial policy