Virology Research Today is a free monthly online journal that collates and summarizes the latest research about Virology, including details on viruses, pathology, classification, definitions.

Persistent low-level viraemia and virological failure in HIV-1-infected patients treated with highly active antiretroviral therapy.

Sungkanuparph S, Groger RK, Overton ET, Fraser VJ, Powderly WG

Washington University School of Medicine, St Louis, MO, USA. ssungkanuparph@yahoo.com

OBJECTIVE: To assess the prognostic significance of persistent low-level viraemia (PLV, defined as persistent plasma viral loads of 51-1000 HIV-1 RNA copies/mL for at least 3 months) in patients who had achieved viral suppression on antiretroviral therapy (ART). METHODS: A retrospective cohort of HIV-infected patients who received ART, were followed-up for > or =12 months, made regular visits to the clinic during which blood tests were performed for an ultrasensitive HIV RNA assay every 3 months, and achieved viral loads <50 copies/mL were evaluated. Virological failure was defined as two consecutive viral load measurements >1000 copies/mL. RESULTS: Of 362 patients, 78 (27.5%) experienced PLV. The demographics of patients with and without PLV were similar. PLV occurred at a mean (+/-standard deviation) of 22.6+/-16.9 months after ART initiation and lasted for 6.4+/-3.4 months. During a median follow-up of 29.5 months, patients with PLV had a higher rate of virological failure (39.7% vs 9.2%; P < 0.001). The median time to failure was 68.4 months [95% confidence interval (CI) 37.0-99.7] for patients with PLV and >72 months for patients without PLV (log rank test, P < 0.001). By Cox regression, patients with PLV had a greater risk of virological failure [hazard ratio (HR) 3.8; 95% CI 2.2-6.4; P < 0.001]. Among patients with PLV, a PLV of >400 copies/mL (HR 3.3; 95% CI 1.5-7.1; P = 0.003) and a history of ART (HR 2.4; 95% CI 1.0-5.7; P = 0.042) predicted virological failure. CONCLUSIONS: PLV is associated with virological failure. Patients with a PLV >400 copies/mL and a history of ART experience are more likely to experience virological failure. Patients with PLV should be considered for treatment optimization and interventional studies.

Published 23 August 2006 in HIV Med, 7(7): 437-41.
Full-text of this article is available online (may require subscription).

© 2005-2008 Virology Research Today. All Rights Reserved.