Primary HIV infection: molecular approaches in diagnosis and monitoring

Objective: The aim of this study was to evaluate, in patients with primary HIV infection (PHI), the modification of HIV molecular parameters (HIV, RNA , and DNA) induced by highly active antiretroviral therapy (HAART) in perip heral blood mononuclear cells (PBMC) and in lymphoid tissue (LNMC). Methods: Nineteen patients with primary HIV infection, 4 women and 15 men w ith an average age of 35 years (range 27-62), were included in this study. Ten patients received 4 drugs: zidovudine plus lamivudine plus saquinavir p lus ritonavir, 7 patients received 3 drugs: zidovudine plus lamivudine plus saquinavir and 2 patients received a different combination of 3 drugs: zid ovudine plus lamivudine plus indinavir. As control group we included 8 pati ents who had been enrolled in a placebo-controlled trial of zidovudine betw een 1991 and 1995: four received placebo and 4 were treated with zidovudine alone. Peripheral blood samples and lymphoid tissue obtained by echo-drive n fine needle biopsies were drawn to monitor molecular HIV parameters. A qu antitative in house PCR method in the HIV gag region was used to monitor vi ral DNA burden and the NASBA system for viremia. Results: A certain heterogeneity in the baseline values of HIV, DNA, and RN A was observed. Early HAART determined a rapid recovery of the CD4 cell num ber with normalisation of the CD4/CD8 ratio in most patients. HIV-RNA level s dropped to undetectable levels after a few months of therapy and HIV-DNA was consistently reduced although it never reached undetectable levels. Lym ph-node biopsies were well tolerated due to the non-invasive sampling, howe ver an optimisation of the method is needed to improve cell recovery. In th e valuable samples the amount of HIV DNA recovered is comparable to that fr om peripheral blood samples, both at baseline and at follow-up.