Coinfection with HIV-1 and human T-Cell lymphotropic virus type II in intravenous drug users is associated with delayed progression to AIDS.
Human T-cell lymphotropic virus (HTLV) type II has spread among intravenous drug users (IDUs), many of whom are coinfected with HIV-1. We have investigated the rate of HTLV-II infection in 3574 Italian IDUs screened for HIV-1, HTLV-I, and HTLV-II from 1986 to the present. HTLV-II proviral load was determined by a real-time polymerase chain reaction specifically designed for tax amplification. The frequency of HTLV-II infection was 6.7% among HIV-1-positive subjects and 1.1% among HIV-1-negative subjects (P < 0.0001). For examination of AIDS progression, a group of 437 HIV-1-monoinfected subjects and another group of 96 HIV-1/HTLV-II-coinfected subjects were monitored. Enrollees were matched at entry by CD4 cell counts and followed for an average of 13 years. HIV-1/HTLV-II coinfection was associated with older age (P < 0.0001) and higher CD4 (P < 0.0001) and CD8 (P < 0.001) cell counts compared with monoinfected IDUs. The number of long-term nonprogressors for AIDS was significantly higher (P < 0.0001) among coinfected patients (13 [13.5%] of 96 patients) than HIV monoinfected patients (5 [1.1%] of 437 patients), showing that HTLV-II exerts a protective role. An increased incidence of liver disease and hepatitis C virus positivity among coinfected IDUs was observed. Five coinfected subjects undergoing antiretroviral therapy showed a significant (P < 0.05) increase in HTLV-II proviral load concomitant to a decrease in HIV-1 viremia, suggesting that the treatment is ineffective against HTLV-II infection.
Turci
Marco
M
Section of Biology and Genetics, Department of Mother and Child, University of Verona, Verona, Italy.
Pilotti
Elisabetta
E
Ronzi
Paola
P
Magnani
Giacomo
G
Boschini
Antonio
A
Parisi
Saverio G
SG
Zipeto
Donato
D
Lisa
Antonella
A
Casoli
Claudio
C
Bertazzoni
Umberto
U
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology*; D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D018450:Disease Progression; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000276:immunology / Q000635:transmission; D015497:HIV-1 / Q000235:genetics* / Q000302:isolation & purification; D015491:HTLV-II Infections / Q000150:complications* / Q000276:immunology / Q000635:transmission; D015367:Human T-lymphotropic virus 2 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007558:Italy; D008297:Male; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D015819:Substance Abuse, Intravenous; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014766:Viremia / Q000453:epidemiology; D044465:White People