Day One: After You've Tested PositiveJanuary 2007 Checking on Your Immune HealthWith most illnesses, we wait until a disease shows up before doing anything about it. "If it ain't broke, don't fix it." But in HIV disease, the immune system starts to "break" immediately, not just when OIs show up. So keeping an eye on the health of your immune system is critically important. Two common ways to do this are: (1) noticing when symptoms occur and (2) getting lab tests done. Each can appear to have advantages and disadvantages. Noticing When Symptoms OccurThis approach waits for active infections and disease to occur. In HIV, this means watching out for such things as thrush (yeast infections), PCP, Kaposi's Sarcoma (KS) lesions and so on. Advantages HIV disease progresses even before symptoms appear. By the time they do appear, treating the underlying problem may be less effective because your body is left with fewer defenses. Getting Lab Tests Done
Advantages Disadvantages Because HIV infection can be a life-or-death matter, it is critical to choose the second approach. Taking a preventive approach makes it possible to:
Some people say they hesitate to act before they're sick because today's treatments are not perfect, hoping to wait for something better to come along. However, no one knows when "perfect" treatments will become available. It is well proven that today's treatments can extend survival time. Although we can't predict the results for every person, we do know what generally happens without treatment. The purpose of preventive action is to slow the progress of HIV disease. This approach is the one that seems to offer the clearest hope. Once infected, you have one chance to manage your disease correctly. So consider your options carefully and learn how to tell when a therapy is or is not working for you. To learn more, read Project Inform's publications, Making Decisions about Therapy and Blood Work: Two Common Tests to Use. Project Inform Treatment Strategy for HIV Disease
Common Blood Tests and What They Tell YouCD4+ Cell Count TestsFor many years, testing the number of CD4 cells was the only lab measure for the effects of HIV disease. Low numbers of these cells (below 200) accurately predict the risk of major infections. Doctors encourage people to start HIV therapy when their CD4 counts are 200–350. However, these are arbitrary numbers used in studies of HIV drugs. By itself, a CD4 count doesn't tell us enough about the state of disease. It only shows that the level of CD4 cells is below normal, to varying degrees. Getting the full picture of your HIV disease requires monitoring your general health and additional tests, especially the viral load test and CD4 percentage. It has become common to put people with CD4 counts below 200 or 300 on preventive treatment for PCP (often using Bactrim/Septra or dapsone), along with all people who have had an initial bout of PCP. Regardless of CD4 count, yearly checking for tuberculosis is becoming increasingly important. Prevention strategies for all of the common OIs are described in Project Inform's publications, Opportunistic Infections Chart and Strategies for Managing Opportunistic Infections.
Normal Range: Below Normal Range: Low Range: Viral Load Tests (PCR)Tests are available that directly measure the activity of HIV in the blood. They provide extra information to describe a more accurate picture of the risk of disease progression. Viral load tests measure the amount of new HIV being produced and released into your blood. Studies show that higher viral loads are associated with a greater risk of losing CD4 cells and then progressing to symptoms of HIV disease. Ideally, an HIV-infected person should have no detectable level of virus, which means that HIV activity is too low to be measured by the tests. Current tests measure down as low as 50 copies of virus. This is associated with the best possible medical outcome. Higher levels -- ranging from about 30,000 (in women) to 60,000 (in men) to upwards of millions of copies of virus -- are linked to higher rates of disease progression. In short, the higher the number, the more rapid the rate of disease progression. Studies of new drugs use viral load tests to measure the effects of the drugs. A good combination of HIV drugs can quickly reduce the level of virus at least ten times and often as much as a thousand times. The goal of therapy is to reduce viral load to as low as possible, preferably below the lowest level detected by the test, below 50 copies. HIV-positive people and their doctors use both CD4 counts and viral load tests to make decisions about if and when to use HIV drugs. These tests also help determine whether a drug is working or not. When HIV levels begin to rise again while using a drug, most doctors believe it is time to switch to another drug or combination of drugs. Also, if your CD4 counts begin falling, reassessing your HIV therapy is warranted. At the very least, viral load tests provide a rational basis for helping some to decide when or whether to use HIV drugs, as well as a tool for determining whether or not a drug combination is working. For more information, read Project Inform's publications, Blood Work: A Useful Tool for Monitoring HIV and Blood Work: Two Common Tests to Use. Final Thoughts on TestingNo single test gives a total picture of immune health or disease progression, but CD4 count and viral load test results taken together over time are very important. As we learn to manage HIV as a chronic illness, these tests provide rational guidance about what treatments to use, when and when not to use them, and how well they're working. To help you chart these various blood tests, use Project Inform's publication, Personal Tracking Charts.
This article was provided by Project Inform. |
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