Objectives: To assess the immunological and virological markers as potential predictors of progression to death in HIV-1 infected < 12 months of age.
Patients and methods: Forty-three HIV-1 infants < 12 months of age were evaluated. None of the children received antiviral treatment, neither their mothers during pregnancy. Plasma viremia was quantified by standardised molecular assay. Virus isolation, evaluation of the non-syncytia-inducing (NSI) or syncytia-inducing (SI) phenotype and kinetic of replication was performed in parallel cultures.
Results: Regarding viral load cut off levels of 5 log10 copies/ml appeared to be the best predictors of progression to death. The mean times of progression to death estimated by Kaplan-Meier method were 61.08 months fir children with viral load below that limit, and 19.16 months above this limit (p < 0.013). When the first viral isolate was NSI the mean time of progression to death was of 73.9 months, whereas it was of 26.7 months when was SI (p < 0.003). When the first viral isolate was slow/low (S/L) the mean times of progression to death was 71.8 months, whereas it was of it was of 19.8 months when was rapid/high (R/H) (p < 0.0003). When the first viral isolate was S/L-NSI the mean times of progression to death was of 73.9 months, whereas it was of 19.4 months when was R/H-SI (p < 0.0004). The hazard rate of progression to death in infants with viral load > 5 log10 copies/ml was 4.7, whereas was of 8.07 in those with SI isolates and of 9.32 in those with R/H kinetics.
Conclusions: Initial HIV-1 biological characteristics are better predictors of progression to death than viral load in untreated infants under 12 months of age. Nevertheless, a correlation exists between viral load over 5 log10 copies/ml and progression to death.