Several assumptions are involved in this process, and it may be that this immunological dysregulation, which culminates in the rapid increase in CD4+ cells and a decrease in the viral load, is a possible explanation for these patients with HIV to manifest, for the first time, the clinical lesions of leprosy with symptoms of intense reactions, after the use of ART (known as “unmasked” IRIS), or in others already diagnosed with leprosy, to present only the inflammatory reaction also after the use of ART (known as “paradoxical” IRS). The gene discussed is CD4; the disease is leprosy.