LOINC Code 21164-9: CD4 cells (Specimen)
21164-9 is a LOINC code used to identify CD4 cells (Specimen) in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Cells.CD4/Gated cells.total. It is commonly used with the system or sample type XXX.
What is this code?
LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Cells.CD4/Gated cells.total. It is commonly used with the system or sample type XXX.
When is it used?
- Used in lab systems, EHRs, and clinical data exchange.
- May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
- Status: DEPRECATED
What it does not mean
- The code identifies the observation or test, not the actual result.
Key facts
- Deprecated CD4 cells/gated cells in Unspecified specimen
- Cells.CD4/Gated cells.total
- CD4 Cells; Cell; CELL MARKERS; Cellularity; Helper T cells; Inducer T cells; L3T4; Leu3; Leu-3; Misc; Miscellaneous; Number fraction; Other; Percent; Point in time; QNT; Quan; Quant; Quantitative; Random; Spec; T4; T-4; To be specified in another part of the message; Tot; Totl; Unspecified; W3/25
Where you may see this code
You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.
Common synonyms
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.