Coinfection with human T-cell lymphotropic virus type I and HIV in Brazil. Impact on markers of HIV disease progression

Abstract

<h3>Objectives.</h3> —To study the effect of human T-cell lymphtropic virus type I (HTLV-I) on markers of human immunodeficiency virus (HIV) disease progression. <h3>Design.</h3> —A retrospective, nested case-control study. <h3>Setting.</h3> —A university hospital outpatient HIV clinic in Rio de Janeiro, Brazil. <h3>Participants.</h3> —Human immunodeficiency virus—seropositive adults participating in a prospective HIV cohort study. <h3>Main Outcome Measures.</h3> —The HIV clinical stage, CD4⁺lymphocyte counts, and other laboratory parameters in 27 individuals infected with HIV and HTLV-I (coinfection) and 99 age-matched, HIV-seropositive, HTLV-seronegative controls (single infection). <h3>Results.</h3> —Variables independently associated with coinfection included higher CD4⁺lymphocyte count (odds ratio [OR], 2.3; 95% confidence limits [CL], 1.3,4.1), higher CD4⁺percentage (OR, 2.0; 95% CL, 1.3, 3.2), β₂-microglobulin level of 254 nmol/L or more (OR, 6.8; 95% CL, 1.3, 35.4), World Health Organization stages 3 and 4 (OR, 4.4; 95% CL, 1.1,18.0), and reporting a parenteral risk factor (OR, 7.4; 95% CL, 1.4, 38.9). When stratified by p24 antigenemia, coinfection was associated with an estimated 82% higher CD4⁺lymphocyte count (<i>P</i>&lt;.05). <h3>Conclusion.</h3> —Coinfection was associated with higher CD4⁺lymphocyte counts, more advanced clinical disease, and higher β₂-microglobulin levels than HIV infection alone. The higher mean CD4⁺lymphocyte count does not appear to offer immunologic benefit. Caution should be exercised when using CD4⁺lymphocytes as a surrogate marker in studies of HIV infection in populations where HTLV-I is prevalent. Further studies are needed to address whether current CD4⁺lymphocyte values for the initiation of antiretroviral therapy and chemoprophylaxis against opportunistic infections in HIV infection are appropriate in coinfection. (<i>JAMA</i>. 1994;271:353-357)