Background: Gut microbial translocation (MT) is considered a major cause of immune activation (IA) and failure of immune reconstitution in HIV infection. This study investigated the relationship of virus replication, IA, CD4 counts and MT in HIV-infected children.
Methods: Lipopolysaccharide, bacterial 16S ribosomal DNA (16SrDNA) and soluble CD14 (sCD14) levels were determined in prospectively collected, stored plasma samples from the Pediatric AIDS Clinical Trials Group Protocol P338, a 48-week study initiated in 1997 to compare efficacy of dual nucleosides with a ritonavir-containing regimen. Results of MT were correlated with study data for T cell IA, plasma viral load and CD4 counts in 85 HIV-infected children (ages 2-17 years) designated as virologic responders or virologic failures (VF) at week 44 based on a cutoff of 400 HIV RNA copies/mL.
Results: Levels of plasma lipopolysaccharide, 16SrDNA and sCD14 were increased in comparison with HIV-uninfected controls and did not decrease at week 44 even in virologic responders. T cell IA was correlated with viral load and sCD14 at entry and with 16SrDNA and sCD14 at week 44 in total patients and in the VF group. Changes in 16SrDNA correlated with changes in IA and negatively with changes in CD4 counts. 16SrDNA was correlated with sCD14 but not with lipopolysaccharide.
Conclusions: MT persists after 44 weeks of antiretroviral therapy in VS and VF patients. In VF, 16SrDNA exhibited relationships to monocyte and T cell IA and CD4 counts but not with viral load, suggesting a dominant role for MT in disease pathogenesis in HIV-infected children.