CD4

Medical abbreviation · Infectious Disease

CD4
Stands forCluster of differentiation 4 (CD4 T-cell count)
CategoriesMedical

CD4 stands for Cluster of differentiation 4 (CD4 T-cell count), an infectious disease abbreviation.

Count of helper T lymphocytes in the blood, normally about 500–1,500 cells/mm3, used to stage HIV infection and decide on preventive treatment. Below 200 cells/mm3 indicates AIDS and the need for Pneumocystis prophylaxis; below 50 raises risk of MAC and CMV disease.

Example: CD4 145 (11 percent); start TMP-SMX DS daily for PCP prophylaxis.

Usage notes

CD4 is a glycoprotein on helper T cells that HIV uses as its main receptor. The CD4 percentage is more stable than the absolute count and is preferred in young children. Once viral load is suppressed and the count stays high, monitoring can be reduced. "CD" designations name hundreds of cell-surface markers.

More infectious disease abbreviations

  • ARF – Acute rheumatic fever
  • ART – Antiretroviral therapy
  • ASP – Antimicrobial stewardship program
  • BCG – Bacillus Calmette-Guérin
  • BSI – Bloodstream infection
  • C. diff – Clostridioides difficile
  • CDI – Clostridioides difficile infection
  • CMV – Cytomegalovirus
  • COVID-19 – Coronavirus disease 2019
  • CRAB – Carbapenem-resistant Acinetobacter baumannii
  • CRE – Carbapenem-resistant Enterobacterales
  • CT – Chlamydia trachomatis

See all 92 infectious disease abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.

This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.