Clinics and Departments

Laboratory Services

Lab Dept:

Flow and Immunology

Test Name:


General Information

Lab Order Codes:



Helper/Suppressor Ratio; T- cells; T, B, and/or NK phenotyping; T, B, and/or NK enumeration; T&B subsets

See also: CD4/CD8 Panel and Comprehensive Immune Status Panel

CPT Codes:

88184 – Flow cytometry, cell surface, cytoplasmic or nuclear marker, technical component only; first marker
88185 x4 – Flow cytometry cell surface, cytoplasmic, or nuclear marker, technical component; each additional marker

Test Includes:

CD3, CD4(CD3+), CD8(CD3+), CD16+56(CD3-), and CD19 relative percentages, absolute values, and a calculated Helper/Suppressor ratio


Test Indications:

Useful for diagnosing an immunodeficiency and to monitor immune status.

Lab Testing Sections:

Flow Cytometry

Phone Numbers:

MIN Lab: 612-813-6280

STP Lab: 651-220-6550

Test Availability:

3 times weekly determined by volume. Transport collected specimen immediately to Flow Cytometry. Routine testing is not available on weekends or holidays. Therefore, specimens cannot be used if drawn the day before a 3 day weekend such as Memorial Day, Labor Day or major holiday that falls on a Monday or Friday.

Turnaround Time:

1 – 3 days

Special Instructions:

See Test Availability and Collection instructions


Specimen Type:

Whole blood


Lavender top (EDTA) tube

Draw Volume:

Draw one of the following:

2 mL blood in a 2 mL EDTA tube
3 mL blood in a 3 mL EDTA tube

Processed Volume:

A minimum of 0.5 mL is routinely used (from a properly filled tube), however more specimen will be used if the alternative two-platform method is used.


Draw blood in EDTA tube, filling to the tube’s intended volume (indicated on label)

Special Processing:

Lab Staff: Keep specimen at room temperature and forward promptly to the laboratory. Do Not centrifuge, refrigerate, or freeze sample.

Patient Preparation:


Sample Rejection:

Specimens will not be processed that are clotted; hemolyzed; greater than 72 hours old; or that have been held or handled at a temperature other than room temperature


Reference Range:

Age-dependant reference ranges will be provided with results

Critical Values:



Poor specimen quality will adversely affect the test results (see Specimen section)

The single platform method is linear when the WBC count of the specimen is between 0.2 k/uL and 29.7 k/uL, and its lymphocyte concentration is between 0.1 k/uL and 9.0 k/uL.


Single-platform 4 color direct immunofluorescence method FDA approved for in-vitro diagnostic usage. Flow cytometric analysis based on CD45 gating strategy.

In cases where the WBC count of the specimen exceeds the linearity limits of the single platform method, an alternative two-platform method will be used.


Centers for Disease Control (2003) Guidelines for performing CD4+ T-cell determinations with CD45 Gating in persons with immunodeficiency virus (HIV). MMWR 52 (No. RR-2): 1-18

MultiTEST IMK Kit Package Insert. Becton Dickinson Immunocytometry Systems. December 2000


1/5/2014: CPT update

  Lab Test Directory
    Microbiology/ Virology
    Other Fluids
    Transfusion Services

  Search Lab Test Directory
    List All Documents

  Lab Staff

  E-mail Lab Services