Co‐infection with HIV‐1/ HTLV‐II and the risk of progression to AIDS and death

Abstract

Human T‐cell lymphotropic virus (HTLV) types I and II were the first discovered human retroviruses. While HTLV‐I has been clearly associated with disease, the health implications of HTLV‐II infection are still unsettled. A prospective epidemiological study of 409 HIV‐infected subjects of different transmission categories was performed to study the presence of HTLV‐II antibodies, and whether HTLV‐II antibodies are associated with the progression to AIDS and to death of any cause. Of 409 subjects, 30 (7.3%) were HTLV‐II positive at study entry; 2 subjects seroconverted during follow‐up. In the HTLV‐II‐positive group 2 were heterosexually HIV infected, 28 (of whom 2 were seroconverters) were IDUs and 2 were homosexual men. When controlling for transmission category, gender, age and CD4+ lymphocyte count at study entry, the relative risk of AIDS progression for the HTLV‐II‐positive group was 2.1 (0.8–5.1, 95% confidence interval (CI)) as compared to the HTLV‐II‐negative group. The adjusted relative risk of dying was 2.1 (1.0–4.3, 95% CI). When studying IDUs separately, the adjusted relative risk of AIDS progression was 2.3 (0.8–6.9, 95% CI) and the relative risk of dying was 2.0 (0.9–4.6, 95% CI). The results of this study suggest that HTLV‐II is a cofactor in HIV disease progression. The number of HTLV‐II‐infected subjects, was, however, small, and insufficient control of confounding factors must be taken into consideration.

Spontaneous Production of C-C Chemokines by Individuals Infected with Human T Lymphotropic Virus Type II (HTLV-II) Alone and HTLV-II/HIV-1 Coinfected Individuals

“…It is uncertain to what extent the quantities of C-C chemokines produced by HTLV-II-infected individuals are able to influence the progression of HIV-1 infection in vivo. At present there is no consensus among available epidemiological studies as to whether HTLV-II infection has a positive or negative effect on HIV-1 disease progression (17)(18)(19)(20). Unfortunately, interpretation of these studies is limited due to the inability to definitively determine the temporal relationship of infection by the two viruses.…”

“…The influence of HTLV-II infection on HIV-1 has not been extensively evaluated, and epidemiological studies have failed to agree upon what, if any, influence HTLV-II might have on HIV-1 disease progression (17)(18)(19)(20). In this report we describe the results of studies to investigate the immunological features of HTLV-II infection and to analyze mechanisms whereby HTLV-II could potentially influence infection with and the progression of HIV-1 in vivo.…”

Clinical Outcomes and Disease Progression among Patients Coinfected with HIV and Human T Lymphotropic Virus Types 1 and 2

“…Conflicting reports suggest variable outcomes among dually infected individuals, including delayed progression to AIDS in some reports and accelerated disease progression in others [5,10,11,[15][16][17]. Interpretation of these study results is limited by incomplete demographic, laboratory, and treatment data and by lack of differentiation of HTLV-I from HTLV-II in many cases.…”

In Vivo Interactions of Ecotropic and Polytropic Murine Leukemia Viruses in Mixed Retrovirus Infections

“…Naturally occurring retrovirus infections are often mixed infections of retroviruses with different properties (5,6,17). Mixed retrovirus infections can be generated by infection with a heterogeneous mixture of viruses, by genetic alterations, such as point mutations or recombination, which occur subsequent to infection, or by infection of a host that already harbors retroviruses.…”