Coinfection with human T-cell lymphotropic virus type I and HIV in Brazil. Impact on markers of HIV disease progression
M. Schechter, L. H. Harrison, N. A. Halsey, G. Trade, M. Santino, L. H. Moulton and T. C. Quinn
Department of Preventive Medicine, Hospital Universitario Clementino Fraga Filho, Federal University of Rio de Janeiro, Brazil.
OBJECTIVES--To study the effect of human T-cell lymph-tropic virus type I
(HTLV-I) on markers of human immunodeficiency virus (HIV) disease
progression. DESIGN--A retrospective, nested case-control study. SETTING--A
university hospital outpatient HIV clinic in Rio de Janeiro, Brazil.
PARTICIPANTS--Human immunodeficiency virus-seropositive adults
participating in a prospective HIV cohort study. MAIN OUTCOME MEASURES--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). RESULTS--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),
beta 2-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 (P < .05).
CONCLUSION--Coinfection was associated with higher CD4+ lymphocyte counts,
more advanced clinical disease, and higher beta 2-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.
