Antiretrovirals do not independently affect T-cell count in HIV negative subjects

Antiretroviral agents do not seem to have a direct effect, independent of suppression of retroviral replication, on T-cell counts in HIV negative individuals.

The findings contrast with the “proliferation hypotheses and the hypothetical braking of lymphocyte apoptosis induced by antiretroviral agents independent of retroviral inhibition,” Drs Vincenzo Puro and Giuseppe Ippolito of the National Institute for Infectious Diseases in Rome, Italy, note in the August 15th issue of the Journal of Acquired Immune Deficiency Syndromes.

On behalf of the Italian Registry on Antiretroviral Postexposure Prophylaxis, the investigators used retrospective data to determine the effects of antiretroviral agents on T-cell counts in health care workers occupationally exposed to HIV. Prophylaxis, if given, had included zidovudine, zidovudine plus lamivudine, or zidovudine plus lamivudine and indinavir at standard doses for 30, 27, and 27 days, respectively.

Among the subjects, 284 received prophylaxis following HIV-1 exposure and 164 did not. The Italian researchers determined that mean CD4 and CD8 cell counts had increased slightly in both treated and untreated patients. These increases were not correlated with the duration of postexposure prophylaxis, sex, or adverse effects.

The data “seem to reject any direct effects of antiretroviral agents on proliferation and redistribution of T lymphocytes,” Drs Puro and Ippolito conclude.