A new study finds that viral load levels can predict the stage 3 and 4 clinical events in children receiving highly active antiretroviral therapy (HAART).

Scientists give the reason for undertaking the study as "...the value of routine viral load measurement in addition to immunological monitoring for prediction of new HIV-related clinical events in children receiving HAART has not been clearly demonstrated".

Treatment of HIV infections is resource based. In resource-rich settings, HIV viral load assays are used to monitor infections. But in a limited setting, immunological and clinical outcomes are the monitor indices for treatment outcomes.

Latin American Children with perinatal infection under the age of 15 were considered for the study. The children were receiving HAART for at least 6 months and were monitored for 2.5 years. New WHO events happened in 15.8% of children. The CD4-defined immunosuppression, viral load, hemoglobin level were related to the risk of a new WHO event.

A viral load greater than 5000 copies/ml doubled the risk of developing a WHO event even after adjusting for all the parameters.

However, monitoring lab parameters once in 6 months during the trial was not as close as possible to the WHO event. The clinical diagnosis of the WHO event was believed without laboratory confirmation. Testing for drug resistance was not carried out and association between viral load and clinical events was underestimated during the trial.

In conclusion, the authors say - "These results suggest that routine measurements of CD4 T lymphocytes and hemoglobin, combined with ability to detect a viral load >5000 copies/mL, would constitute an effective approach to monitoring children receiving HAART for clinically relevant treatment failure."

"The ability to detect viral load at a level of >5000 copies/mL, unlike virological detection at thresholds of 50 or even 400 copies/mL, may be more readily attainable with quantitative RNA assays from dried blood spots, making this approach to virological monitoring for treatment failure more feasible in a broad range of resource-limited settings."

This study was reported in the December 1st issue of Clinical Infectious Diseases. The associated research was carried out by Ricardo Oliveira, MD, at Brazil's Universidade Federal do Rio de Janeiro together with his colleagues from the NISDI (National Institute of Child Health and Human Development International Site Development Initiative) study group.