CD4 and HIV infectious disease: Direct evidence of alterations in the composition of the gastrointestinal tract microbiome has also been found for some bacterial taxa: Current data indicate increases in commensals that can be pathogenic such as Pseudomonas in the feces of subjects with HIV infection; and decreases in mostly beneficial commensals such as Lactobacilli and Bifidobacteria [6].Furthermore, prebiotics have been tested in HIV in an effort to alter the microbiome to have a more favorable composition, resulting in reduced CD4+ T cell activation and improvement in NK cell activity [8].