As a person living with HIV, you will likely have regular visits with your doctor to monitor your health. When you meet with your doctor, you will be able to discuss any new symptoms or problems you may be experiencing, and your doctor may do a physical exam to follow up on specific issues. You will also get blood drawn at the lab every couple of months. Your blood will be tested for several things. Two of the most important blood tests will be done to measure your CD4 count and your viral load. Many other routine tests can spot potential health issues even if there are no noticeable symptoms.
Every time you see your doctor, tell him or her how you have been feeling, especially if you have noticed any new or unusual symptoms. This could include fever or night sweats, diarrhea or upset stomach, headaches, rashes, a persistent cough, trouble breathing or anything that seems unusual. Your doctor will probably follow up with some questions. Take your time and answer honestly. It can be difficult to judge what's worth mentioning, but err on the side of caution. Not every little ache and pain is serious, but let your doctor know about anything persistent or anything that seems out of the ordinary. Better to spend an extra minute or two than to miss something important.
Any symptoms you're noticing may or may not be HIV-related -- but the first step is to get them out in the open so you can find out what's causing them. This also includes changes in your mood, mental health and behaviour: if you've been feeling down or depressed or acting in ways you don't normally, say so.
Your CD4 count is the single most important measure of how strong your immune system is -- that is, how well you are able to fight off infections. This, in turn, tells you whether you should start treatment sooner or later.
Generally, you should be getting your CD4 count checked every three to six months. It may make sense to check it more often if you've been stressed or sick. CD4 counts are measured in cells per cubic millimetre (cells/mm3 -- a cubic millimetre is about the size of a pinhead). CD4 counts generally drop as HIV does more damage to your immune system. If your CD4 count falls too low, the risk of serious opportunistic infections increases. However, even lower-than-normal counts may still be "high enough" -- that is, high enough to keep you healthy, without significant danger of serious infections.
In most HIV-positive people who are not on treatment, the CD4 count declines by an average of 50 to 100 cells each year. Declines in CD4 counts merit more attention if they fall faster than they have in the past or if they put you at greater risk of illness. As counts fall farther below 500 cells, the need to start HIV treatment becomes more pressing.
The number of CD4 cells can also be reported as a percentage of the total number of lymphocytes. The normal range is from 32% to 50%.
While your CD4 count can fluctuate a fair amount, the CD4 percentage does not normally vary as much. Looking at both of these numbers may give you and your doctor a better picture of the state of your immune system. If your absolute CD4 count takes a dip, but your CD4 percentage stays the same, you may not need to be as concerned about the decrease in count -- it's probably due to an overall variation in your white blood cells rather than an HIV-related drop in your CD4 cells.
If, however, your CD4 count and percentage both decline at the same time, that's probably worthy of attention. If your CD4 percentage falls below 20%, you may be at risk for Pneumocystis pneumonia (PCP). If your CD4 percentage falls below 15%, you are probably at risk for other opportunistic infections as well.
Your viral load is the amount of HIV in your blood. Viral load tests measure the amount of HIV in a sample of blood. The results are reported as the number of copies of HIV genetic material (called RNA) in a millilitre of blood (copies/ml -- a millilitre is about the size of a small bean). The standard tests in Canada can measure levels as low as 40 to 50 copies/ml. Below this level, your virus is considered undetectable. (There are more sensitive viral load tests, but these are used only in specialized laboratories and in some clinical trials.) Without treatment, a person's viral load can be as high as millions of copies/ml.
An "undetectable" viral load does not mean that HIV has been wiped out. It only means that the amount of HIV in your blood is too low to measure using routinely available tests. If you stop taking your treatment or if the HIV in your body becomes resistant to your antiretroviral drugs, your viral load will once again become detectable (that is, greater than 40 or 50 copies/ml).
If you are not on HIV treatment, the results of your viral load test will give you a rough indication of how fast you can expect your CD4 count to decline. In general, CD4 counts tend to decline faster in individuals with higher viral loads who are not on HIV treatment, and they stay stable longer in people with lower viral loads. However, this varies among individuals.
If you are on HIV treatment, your viral load is the most important measure of whether or not your treatment is working. The main goal of treatment is to reach an undetectable viral load within three to six months of starting treatment (although it might take longer if your viral load was very high to begin with). After your viral load becomes undetectable, the goal is to keep it that way.
If you are on treatment and your previously undetectable viral load becomes measurable, this indicates that the drug combination you are taking may no longer be fully suppressing the HIV. This may be a temporary "blip" and your viral load may go back to being undetectable the next time you test it (especially if it only rose to a very low level). These blips can occur every now and then in people on successful treatment, especially after vaccinations and temporary infections like the flu. However, if you are on treatment and two or more tests in a row show a detectable viral load, then you and your doctor need to figure out why this might be happening. It could be due to any of the following factors:
It may be time to consider a treatment change. See "Changing Treatment" for a full discussion of how to handle such "treatment failure."
Whether or not you are on treatment, you will likely be having "blood work" done regularly. Regular lab analysis of your blood can screen for many possible problems.
Your complete blood count (CBC) will probably be measured at each visit. The CBC checks all the major types of blood cells, including infection-fighting white cells, oxygen-carrying red cells and the platelets responsible for blood clotting. If any of these are present in abnormal numbers (too low or too high), this can alert you and your doctor to possible problems to keep a close eye on or investigate further.
Although CD4 and CD8 cells are especially important for people with HIV, your CBC may also include a detailed look at other kinds of immune cells, such as your total white blood cells, lymphocytes and neutrophils (see "Immune Cells").
Several different blood tests are used to track your liver health. Various types of liver damage or impaired function can affect your levels of liver enzymes. These liver enzymes include AST (aspartate aminotransferase), ALT (alanine aminotransferase), AP (alkaline phosphatase), GGT (gamma-glutamyltranspeptidase), a waste product called bilirubin, and a protein called albumin. Abnormal levels of any of these substances should alert you and your doctor that something (perhaps viral hepatitis, alcohol, recreational or prescription drugs) may be stressing or damaging your liver.
Your kidney health can be monitored by blood tests that measure your levels of urea and creatinine. Abnormally high levels could suggest that your kidneys are not functioning normally. Urine tests (urinalysis) can also check for things that should not be present in the urine, such as blood, protein, glucose (sugar) and white blood cells.
Blood sugar, or blood glucose, tests are an important part of monitoring the health of HIV-positive people. Some people on HIV treatment have high blood sugar levels, which should be carefully monitored. Abnormally high levels (called diabetes in the most severe cases) can lead to many health problems if not treated.
Blood fat, or lipid, levels are an important measure of your cardiovascular health -- the health of your heart and arteries. High levels of cholesterol, especially the "bad" cholesterol (low-density lipoprotein, or LDL) can lead to heart disease and hardening of the arteries. Antiretroviral medications can raise the levels of "bad" cholesterol and another type of fat called triglycerides. Blood tests can also measure your "good" cholesterol (high-density lipoprotein, or HDL), which is good for your heart health and helps to clear "bad" cholesterol from the bloodstream.
Many experts and advocates believe that people with HIV should get bone scans regularly, due to an increased risk of thinning of the bones (osteopenia and osteoporosis).
Many of your lab results, such as your CD4 count, can vary over the course of a day or if done at different labs, and can be affected by many other factors as well. It's best to have your tests done at the same time of day, at the same lab, and (if you're premenopausal) at the same time during the menstrual cycle. You may want to always be tested first thing in the morning, before eating or exercising. (Many labs require blood to be drawn for CD4 counts and viral load tests in the morning, anyway.) Some tests have to be done on an empty stomach -- in particular, blood sugar and lipid levels. Just make sure you follow any specific instructions for the tests you're doing.
Getting a vaccination (such as the flu shot) or fighting off an infection (such as a cold or the flu, especially if you have a fever) can temporarily raise your viral load and lower your CD4 count. In these cases, it may make sense to delay your blood tests for a couple of weeks. Anything else unusual that has gone on around the time of your blood tests -- such as drinking more alcohol, sleeping less or being more stressed than usual -- may affect your results.
In general, if any single CD4 count or viral load measurement seems out of line, a repeat test will reveal whether the difference is a new trend or just a "one-off." The overall trends in your results are more important than any single result.
Below, we've included a set of sheets you can use to keep track of your lab results, medications, symptoms and other key pieces of health information. There are also tools available online that can help you keep track of other lab results or graph them over time. Here are a couple you can try:
Monitoring your health -- online learning module covering CD4 counts, viral load and other tests used to track your health
HIV Viral Load Testing -- informative brochure on the viral load test and how it fits into your treatment plan
In-depth Fact Sheets on AIDS-related infections and cancers and HIV transmission
The Positive Side -- health and wellness magazine for people with HIV, featuring such articles as:
Look in the e-zine index for more (www.positiveside.ca).
These and many other relevant resources can be accessed on CATIE's website (www.catie.ca), through the CATIE Ordering Centre or by calling CATIE at 1-800-263-1638.