The question of when to start ART in HIV-positive TB patients has been addressed by the above-cited RCTs [5], [6], [7], [8], [50] and - based on their findings - HIV and TB guidelines recommend that among HIV-positive TB patients with CD4 less than 50 cells/mm3, ART should be initiated within 2 weeks from TB treatment start and if CD4 above 50 cell/mm3, within 8 weeks [51], [52], [53], [54], [55]. This evidence concerns the gene CD4 and tuberculosis.