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Test Code IMDEF Immunodeficiency Panel

Collection Container

Lavender EDTA (preferred),

Green top sodium heparin or lithium heparin (acceptable)

Specimen Required

Place specimens in a bag near the flow cytometry rack at LCRI.  The tubes should remain lying down.  Do not place upright in the rack.  

Specimen Volume

1 mL Lavender EDTA (preferred),

Green top sodium heparin or lithium heparin (acceptable)

Minimum Specimen Volume

1 full lavender top Microtainer™

Special Handling Instructions

An additional lavender top (EDTA) tube must be collected at the same time (within 6 hours maximum) as the IMDEF so that a complete blood count with differential (CBCD) may be ordered (See complete blood count with differential).  If a CBC is ordered on the requisition please order CBDIF.



Transport Temperature

Room Temperature

Specimen Stability

Transport specimen to the Flow Cytometry laboratory as soon as possible.

Reasons for Rejection

Specimen refrigerated or exposed to extreme heat; specimen clotted or hemolyzed; specimen more than 48 hours old when received in the laboratory.


Numeration of specific subpopulations with monoclonal antibodies to lymphocyte antigens by flow cytometry.

Reference Ranges


CD3+/CD4+ (T-helper) cells:  39-64%, 524-1556 cells/mm3

CD3+/CD8+ (T-suppressor) cells:  9-31%, 116-762 cells/mm3

CD3+ (total T-cells) cells:  60-68%, 679-2382 cells/mm3

CD19+ (B-cells) cells:  6-26%, 83-616 cells/mm3

CD56+/CD3- (Natural Killer) cells:  3-20%, 41-411 cells/mm3

CD4/CD8 ratio:  1.345-6.400

Turnaround Time

1-2 days

Day(s) and Time(s) Performed

Draw anytime. Test performed day shift Monday-Saturday; not on Sunday or holidays (Holidays include the weekdays celebrated by Baystate Medical Center when an actual holiday falls on a weekend).  The specimen is acceptable as long as it is received by the flow cytometry laboratory within 48 hours of collection.


Additional Information

The demonstration of a reversed T-helper: T-suppressor ratio (<1) is important in the diagnosis of acquired immune deficiency syndrome (AIDS) and also helps explain pathogenetically the multiple recurrent opportunistic infections which comprise that illness. The absolute number of T4 cells is crucial in instituting and following treatment with anti-retroviral therapy (ART).  Since the number of CD4 cells is an expression of HIV-mediated cell damage and the resultant immunodeficiency, sequential measurements of CD4 counts are critical in HIV infection in monitoring disease progression, determining prognosis, and monitoring therapies.

CPT Code





Units of Measure

(%) and (k/mm3)