The number of white blood cells infected by the AIDS virus rises sharply in the year before virus-infected males actually develop the disease, says a study that may lead to speedier treatment for AIDS victims. While the existing test to detect the increase in AIDS-infected cells is too time-consuming and expensive for routine use, the U.S. Centers for Disease Control is trying to develop a simpler test that could predict when an infected person will get full-blown AIDS, said the CDC's Janet Nicholson. Such a test would help doctors decide when the benefits of giving patients certain toxic anti-AIDS drugs outweigh the risks, said Dr. Paul Volberding, associate professor of medicine at the University of California, San Francisco, and AIDS program director at San Francisco General Hospital. ``If we knew that somebody was getting close to the point of developing AIDS, we would want to treat the person at that point, even if he hadn't developed full-blown AIDS,'' he said. Nicholson, the CDC's clinical immunology chief, presented her findings Monday during the annual meeting of the Federation of American Societies for Experimental Biology. She and her colleagues spent three years regularly testing blood cells from 15 homosexual Atlanta men who were infected by the virus and had chronic swelling of lymph glands but didn't suffer AIDS. Six of the 15 subsequently developed AIDS, Nicholson said. She said in the year before those symptoms became apparent, the six showed a 25-fold increase in the number of AIDS virus-infected peripheral blood mononuclear cells _ a class of white blood cells. If a simple test could show that someone infected with the virus soon will get AIDS, doctors could better decide when to prescribe AZT and antibiotics that prevent pneumocystis pneumonia and other infections that kill AIDS patients once the virus has crippled their immune systems, Volberding said. AZT, or azidothymidine, is believed to slow progression of AIDS. From a scientific standpoint, ``learning what a person's risk of developing AIDS is over time is a very important one,'' he said. But Nicholson and Volberding acknowledged that some AIDS-infected people may not want to learn that they soon will develop disease symptoms. Nicholson said researchers previously knew that people infected with AIDS show reduced numbers of one type of disease-fighting white blood cell, called T4-helper cells, while the infection progresses. Her study found that the number of helper cells decreases more quickly and the number of AIDS-infected cells rises sharply in infected patients who go on to develop overt AIDS symptoms. ``It's not clear yet whether everyone who is infected will develop disease,'' she said, adding that her findings point the way toward determining which patients are likely to do so. AIDS, or acquired immune deficiency syndrome is caused by a virus that damages the body's immune system, leaving victims susceptible to death from infections and cancer. The CDC estimates that 1 million to 1.5 million Americans have been infected with the virus, and of that total, 20 percent to 30 percent will develop AIDS by the end of 1991.
