CD4 and AIDS: Nowadays though, ART is recommended irrespective of CD4 cell count [6, 7], mainly due to the results of two critical trials [10, 11]; both the TEMPRANO [10] and the START [11] trial demonstrated that immediate initiation of ART, with CD4 cell count above 500 cells/μl, was associated with decreased risk of death, severe HIV-related illnesses and serious non-AIDS related events.