NEW YORK--The more that is learned about the natural history of the human immunodeficiency virus (HIV), the stronger the case for early intervention. Recent research confirms "the notion that HIV infection is a dynamic process throughout the course of infection," said H. Clifford Lane, MD, clinical director, National Institute of Allergy and Infectious Diseases (NIAID).
Speaking at a CME program on the management of HIV-infected patients, jointly sponsored by the Center for Bio-Medical Communication and AmFAR (American Foundation for AIDS Research), Dr. Lane said that the dynamic balance between viral burden and CD4+ T cell levels remains the primary indicator of the progress of the disease (see box).
Within 3 to 6 weeks of primary infection, levels of virus are observed to peak and then begin to decline. It is hypothesized that this indicates the beginning of an immune response.
"The strength of the immune response at this critical juncture seems to have a long-lasting impact on the patient," he said. Patients who are able to control the virus, as evidenced by low levels of HIV RNA and diverse T-cell immune response, do much better than those whose response is more restricted and whose levels of HIV RNA are higher.
Clinically, those patients with the most severe symptoms tend to be the ones who show the highest propensity for rapid progression, he said.
Nonetheless, the majority of patients eventually experience a decline in CD4+ T cell count and an increase in viralburden, resulting in disease progression. It now appears that so-called long-term nonprogressors are merely part of a continuum, Dr. Lane commented.
He said that certain qualitative changes in the immune system have profound implications for therapeutic intervention and underline the importance of intervening at the earliest possible moment.