Using CD4 counts to evaluate the stages and epidemiology of HIV infection in South Carolina public clinic patients.

Abstract

CD4 lymphocyte counts decrease with the duration of human immunodeficiency virus (HIV) infection. We used CD4 counts collected for clinical reasons to evaluate the stage of HIV infection and the epidemiology of recent HIV infections among attendees of South Carolina's public health clinics. We measured the CD4 T-lymphocyte counts of persons newly diagnosed with HIV infection April 1989 through June 1990 at South Carolina public health clinics who returned for follow-up. Of 812 newly diagnosed HIV-infected health department patients, 420 (52%) had their CD4 lymphocyte counts measured. Of these 420, 51 (12%) had CD4 counts of < 200, the level below which prophylaxis for pneumocystis pneumonia prolongs survival, and 193 (46%) had CD4 counts of < 500, the level below which zidovudine may prolong disease-free survival. The highest CD4 counts (> or = 900), which are associated with more recent HIV infection, were more common in females. In South Carolina, almost half of newly reported HIV-infected persons who agreed to CD4 testing at the health department might benefit from immediate drug therapy. Within this population, women may be an emerging risk group that requires specifically directed HIV prevention efforts.