No specific HIV characteristics (CD4 cell count value, plasma HIV RNA load, HIV-related diagnosis, or management of antiretroviral therapy) were clearly identified as predictors of ICU mortality [6,8-13,15-21], except in one study where the majority of ICU patients had an AIDS-defining illnesses, in which very low CD4 T-cell count (<50 cells/mm3) was found to be associated with ICU mortality [17]. Here, CD4 is linked to AIDS.