Longitudinal comparison between plasma and seminal HIV-1 viral loads during antiretroviral treatment Comparação longitudinal entre cargas virais seminais e plasmáticas do HIV-1 durante terapia anti-retroviral

This study was designed to investigate the impact of anti-retroviral therapy on both plasma and seminal HIV-1 viral loads and the correlation between viral loads in these compartments after treatment. Viral load, CD4+ and CD8+ T-cell counts were evaluated in paired plasma and semen samples from 36 antiretroviral therapy-naïve patients at baseline and on days 45, 90, and 180 of treatment. Slopes for blood and seminal viral loads in all treated patients were similar (p = 0.21). Median HIV-1 RNA titers in plasma and semen at baseline were 4.95 log10 and 4.48 log10 copies/ml, respectively. After 180 days of therapy, the median viral load declined to 3.15 log10 copies/ml (plasma) and 3.2 log10 copies/ml (semen). At this timepoint 22 patients presented HIV-1 viral load below 400 copies/ml in either plasma or semen, but only 9 had viral loads below 400 copies/ml in both compartments. Key-words: Viral load. Semen. HIV-1. Antiretroviral therapy. Plasma. Resumo Este estudo foi desenhado para investigar o impacto do tratamento com anti-retrovirais na evolução das cargas virais plasmáticas e seminais do HIV-1. A carga viral do HIV-1 e a contagem de linfócitos T CD4+ e CD8+ foi determinada em amostras pareadas de sangue e sêmen de 36 pacientes virgem de tratamento nos dias 0, 45, 90 e 180 após o início da terapia. As curvas de declínio das cargas virais plasmática e seminal foram semelhantes (p= 0.21). As medianas da carga viral plasmática e seminal no pré-tratamento (dia 0) foram 4.95 e 4.48 log10 cópias/ml, respectivamente. Seis meses após o início da terapia, a mediana da carga viral plasmática era 3.15 log10 cópias/ml e a seminal 3.2 log10 cópias/ml. Neste mesmo periodo, 22 pacientes apresentavam carga viral abaixo de 400 cópias/ml no plasma e/ou sêmen, enquanto apenas 9 pacientes apresentavam carga viral abaixo do limite de detecção nos dois compartimentos. Palavras-chaves: Carga viral. Sêmen. HIV-. Terapia antiretroviral. Plasma. 1. Cellular and Molecular Immunology Laboratory, Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, ES, Brazil. 2. Santa Casa de Misericórdia de Vitória, Vitória, ES, Brazil. Address to: Dr. Rodrigo Ribeiro-Rodrigues. Núcleo de Doenças Infecciosas/CBM/UFES. Av. Marechal Campos 1468, Maruípe 29040-091 Vitória, ES, Brazil. Tel: 55 27 335-7207, Fax: 55 27 335-7204 e-mail: [email protected] Recebido para publicação em 15/4/2002 Aceito em 10/11/2003 Despite the fact that HIV-1 was first recovered from semen samples in 1984, and sexual activity continues to be the most common form of HIV transmission, little is known about the impact of seminal viral load on HIV-1 infection1 8. A wide variety of biological and behavioral factors have been associated with the risk of sexual transmission of HIV-114. Recently, a strong association between HIV-1 plasma viral load and the risk of heterosexual transmission was reported13. It has been suggested that high levels of HIV-1 replication probably contribute to both rapid disease progression and enhanced sexual transmission3 5 18. Small shortterm studies have demonstrated that antiretroviral therapy reduces both blood and seminal viral load and may diminish HIV transmission6 7 18. We have shown that the correlation between plasma and seminal viral loads in therapy-naïve patients decreases in parallel with declining CD4 cell counts. The current study was conducted to prospectively evaluate the impact of antiretroviral therapy on HIV viral loads in plasma and semen of antiretroviral-naïve HIV-1+ patients; and, to compare viral loads in both semen and plasma compartments, with peripheral blood T-cell counts at baseline and during treatment.