Time Sensitive

Ordering Recommendation

Absolute CD4 count is sufficient for routine HIV monitoring.




Quantitative Flow Cytometry




1-2 days

New York DOH Approval Status

Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.

Specimen Required

Patient Preparation

Lavender (EDTA), pink (K2EDTA), or green (sodium or lithium heparin). Hemogard tubes are preferred for laboratory automation and safety.

Specimen Preparation

Transport 4 mL whole blood. (Min: 0.5 mL)

Storage/Transport Temperature


Unacceptable Conditions

Clotted or hemolyzed


Specimens must be analyzed within stability times provided. Some medications may affect immunophenotyping results
and should be listed on the patient test request form.
This test is not approved for New York State Clients.


EDTA: Ambient: 72 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Heparin: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable

Reference Interval

Effective November 16, 2015

Reference Interval Tables:
Pediatric reference values (0 - 6 days up to 10 - 15 years) taken from Scandinavian Journal of Immunology 2012; 75, 436-444.
Adult and Geriatric (16 - 64 and 65 plus years) ranges were developed in-lab.

Test Number Components
0-6 days
1 week - 1 month
2-4 months
5-8 months
9-14 months
15-23 months
2-4 years
5-9 years
10-15 years
16-64 years
64 years or older
% CD4 26-62 % 39-69 % 37-69 % 27-81% 25-86% 16-91% 25-66% 26-61% 20-65% 32-64% 35-68%
Absolute CD4 1000-4800 cells/µL 1500-6000 cells/µL 1600-6500 cells/µL 1000-7200 cells/µL 1300-7100
400-7200 cells/µL 500-2700 cells/µL 400-2500 cells/µL 400-2100 cells/µL 430-1800 cells/µL 490-1600 cells/µL

Interpretive Data

The CD4 cells are Helper T-cells expressing both CD3 and CD4. CD4 percentage is reported as a percent of total lymphocytes. CD4 T-cells levels are a criterion for categorizing HIV-related clinical conditions by CDC's classification system for HIV infection. The measurement of CD4 T-cell levels has been used to establish decision points for initiating P. jirovecii prophylaxis, antiviral therapy and to monitor the efficacy of treatment. The Public Health Service (PHS) has recommended that CD4 T-cell levels be monitored every 3 to 6 months in all HIV-infected persons.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)


This test is designed for enumerating the percent and absolute cell count of CD4 Helper T-cells in lysed whole blood. Whole blood is added to fluorochrome-labeled antibodies that bind specifically to cell surface antigens on lymphocytes. After incubation, lysing and fixation, percent and absolute counts are enumerated utilizing an internal quantitation standard. Additional CBC data is not required. 

During HIV infection, antiviral therapy is often initiated when the absolute CD4 count drops below 500 cells/µL. When the absolute CD4 count drops below 200 cells/µL, therapeutic prophylaxis against PCP and other opportunistic infections may be initiated. When the absolute CD4 count drops below 100 cells/µL, prophylaxis against Mycobacterium avium complex is recommended.

For longitudinal studies involving serial monitoring, specimen collections should be performed at the same time of day.

Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
0095621 Lymphocyte Subset Panel 2 Information 45265-6
0095906 Absolute CD4 24467-3
2012857 % CD4 8123-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • CD4
  • CD4 and absoute Count
  • Helper T-Cell level
  • Immune Status-Flow Cytometry
  • P. jiroveci prophylaxis determination
Lymphocyte Subset Panel 2 - CD4 Percent and Absolute