Hardbeatnews, LOS ANGELES, CA, Fri. Oct. 21, 2005: A new study has discovered that the deadly disease, AIDS, consistently injures the brain's motor, language and judgment centers, but left other areas alone.

The UCLA/University of Pittsburgh imaging study, the first of its kind, found that AIDS is selective in how it attacks the brain and that drug therapy does not appear to slow the damage.

“The brain provides a sanctuary for HIV where most drugs cannot follow," Paul Thompson, first author and associate professor of neurology at the David Geffen School of Medicine at UCLA, stated.

High-resolution 3-D color scans created from magnetic resonance images (MRI) vividly illustrated the damage in the study that was published online by the Proceedings of the National Academy of Sciences. Areas of tissue loss glowed red and yellow, while intact regions shone blue and green.

Thompson's laboratory used a new 3-D brain-mapping technique developed at UCLA to analyze the MRIs of 26 people diagnosed with AIDS, and then compared the scans to those of 14 HIV-negative people. The brain scans measured the thickness of gray matter in various regions of the cerebral cortex.

The University of Pittsburgh diagnosed and scanned the AIDS patients; all 26 subjects had lost at least half of their T-cells, the immune cells targeted by HIV. None had experienced AIDS‑related dementia, and 13 were on highly active antiretroviral therapy.

"The brain scan really catches AIDS red-handed, allowing us to see precisely where the damage is," Thompson observed. "For the first time, we can understand why motor skills deteriorate with AIDS, because the virus attacks the motor centers on top of the brain."

"We saw up to a 15-percent tissue loss in the brain centers that regulate motor skills, such as movement and coordination," he added. "This helps explain the slowed reflexes and disruption of balance and gait that often affect people with early AIDS."

The researchers were most startled to see no difference in tissue loss between the patients taking highly active antiretroviral therapy and those who were not.

"This was the most terrifying aspect of our findings," Thompson said. "Even though antiretroviral drugs rescue the immune system, AIDS is still stalking the brain. A protective barrier prevents drugs from entering the brain, transforming it into a reservoir where HIV can multiply and attack cells unchecked."

The scientists hail brain imaging as a useful method for monitoring AIDS and evaluating new drugs' effect on disease progression. The technique can be powerfully applied to gauge patients' response to therapy, even before the onset of dementia or opportunistic infections.

One in 100 people aged 15 to 49 is infected with HIV, the fourth-leading cause of death worldwide. In 2004, 40 million people were living with the disease. Forty percent of AIDS patients suffer from progressive neurological symptoms, typically leading to death. The Caribbean is the second-most affected region in the world. Among adults aged 15–44, AIDS has become the leading cause of death. – Hardbeatnews.com