Viral Load Testing. - TheBody.com's Bulletin Boards

"Taking Unnecessary Tests: A Waste of Valuable Resources

Rick Sowadsky

May 1998

Whenever we do tests for any illness, they should only be done when there is a true clinical need for those tests, rather than ordering them just because the patient wants it.
In my years of experience working in this field, I have found that the vast majority of people who have requested tests like PCR tests, viral load tests, CD4 counts, antigen tests, etc., for diagnostic purposes, have been at extremely low risk for HIV. In fact, the people who have requested these tests the most, were often those at the least risk of infection. Most of the people requesting these tests for diagnostic purposes have been at such low risk, that even antibody tests were unnecessary. For the vast majority of people requesting these tests, the true issue was not HIV. Rather, the true issues were those of guilt, irrational fear, etc. Lab tests are designed to diagnose or monitor medical problems. They are not designed to solve mental health problems like guilt and fear. Mental health problems are best solved with mental health solutions (counseling). When lab tests are used unnecessarily, or for the wrong purposes, they often lead to more confusion for the patient (and more anxiety), and do not solve the true underlying problem. Many people who have taken these tests, ended up taking them multiple times, constantly fearing that their negative test results were wrong. Even after taking these tests, for many people, the fear of having HIV continued. In other words, PCR tests, viral load tests, etc. did not solve the true underlying problem.

In regard to the cost issues of taking clinically unnecessary tests:

Many people have stated that because they paid for the tests themselves, this did not affect healthcare costs. On the contrary, even if you pay for tests yourself, it ultimately DOES increase healthcare costs. This is because when tests are done unnecessarily, it costs extra money for the lab to hire and train additional staff to do those tests. In addition, it costs the lab extra money to purchase additional equipment to run those unnecessary tests. When unnecessary tests are performed, this further limits our already limited healthcare resources. In fact, it is for this reason that insurance companies will not pay for unnecessary tests. With limited money to pay for healthcare, and to prevent further healthcare rationing in the future, like it or not, we have to start looking at healthcare costs. Testing for any disease should not be done just because the patient asks for it. Testing should only be done if there is a legitimate clinical need for these tests. In fact, sometimes taking unnecessary tests can cause more problems than solutions, as discussed below.

The following are some circumstances when HIV related tests are unnecessary:

When the person is at low risk for HIV. Generally speaking, there is no need for low risk people to get tested, since it would be unlikely for a low risk person to be infected in the first place. If a low risk person is fearful of having HIV, in such cases, mental health counseling is often a better way for a person to spend their time and money, in order to solve the TRUE problem.

When the patient insists on getting the test, even though the tests are not clinically necessary.

When tests are used for purposes, other than what they were designed for (as discussed below).

Let me review with you some HIV tests, including when they are necessary, and when they are not necessary.

CD4 Cell Counts:

These tests are not designed for the diagnosis of HIV, and cannot be used for that purpose. There are many things that can affect a CD4 cell count (both very high and very low) that are not related to HIV. In addition, a person can have HIV and still have a normal CD4 cell count. So if you have a low CD4 cell count, it does not necessarily mean you have HIV. Likewise, if you have a normal CD4 cell count, it does not necessarily mean that you do not have HIV. The purpose of these tests is to clinically monitor people who have already been diagnosed with a disease known to affect these cells. For example, in the case of HIV, these tests are used to monitor people ALREADY KNOWN to have HIV, to see if treatment is necessary, or to see how well a person is responding to treatment. It is important to use these tests for their intended use. When tests are used for purposes other than their intended use, this often causes more confusion (and anxiety) for the patient.

Viral Load Tests:

These tests are not normally used to diagnose HIV. This is because a person can sometimes have a viral load "below detectable limits" yet still have the virus. In other words, it is possible to have HIV, and the test may not be able to detect the infection. In addition, cross-reactions can sometimes cause very low viral load counts, even in uninfected persons, making them think that they are infected, when they actually are not. These tests are intended to clinically monitor people ALREADY KNOWN to have HIV, to see if treatment is necessary, or to see how well a person is responding to treatment. When tests are used for purposes other than their intended use, this often causes more confusion (and anxiety) for the patient. There is a specific situation when the viral load test can be used for diagnostic purposes, as discussed below in the paragraph, "When are these tests recommended to help diagnose HIV?".

Antigen tests:

The p-24 antigen test will pick up an infection an average of 6 days prior to a person testing antibody positive. The p-24 antigen tests will often show positive 2-3 weeks after an initial infection. However, not all recently infected persons have detectable levels of p-24 antigen in their blood. So a negative p-24 antigen test does not necessarily mean that the person is not infected.

The primary use of these tests is as a supplemental test in screening the blood supply (IN ADDITION TO antibody tests). These tests are also sometimes used to clinically monitor how well a person is doing, who is ALREADY KNOWN to have HIV. There is a specific situation when the antigen test can be used for diagnostic purposes, as discussed below in the paragraph, "When are these tests recommended to help diagnose HIV?".

Let me also stress that the p-24 antigen test alone CANNOT be used to diagnose HIV infection. Remember, this test will not always pick up an infection. A p-24 antigen test (whether positive or negative) must always be used alongside other HIV diagnostic tests, before a persons HIV status can be determined.

Qualitative PCR tests:

The DNA Qualitative PCR can be used for diagnostic purposes, but there are limitations to its use. Although it can often pick up an infection after about 1 month after an exposure, it will not always detect the infection. It is NOT designed to do routine screening in adults. It is used primarily for:

Research applications, where the test can be repeated multiple times to rule out inaccuracies.

Testing in babies less than 18 months of age, where antibody tests are not reliable.

Testing in persons with other diseases of the immune system where antibody tests may not be reliable.

Testing in persons who repeatedly test indeterminate on antibody tests. An indeterminate antibody test occurs when these tests cannot determine whether a person is infected or not. Indeterminate antibody tests occur very rarely.

Other UNUSUAL circumstances.
When we do Qualitative Diagnostic PCR's, we often do them more than once (and often in combination with other diagnostic tests, like antibody tests), just in case the test did not give an accurate result. This test is very difficult for labs to perform, and it is therefore very expensive. The more difficult the test, the more the chances for inaccurate test results. If the test is done just right, it can give an accurate result. But because it is difficult for labs to do, there is a greater chance for inaccurate results (as compared to antibody tests). Usually only regional reference labs will do this test, not the vast majority of clinical labs.

Many people have requested these tests, since they do not want to wait 6 months to take an antibody test. Doing these tests is clinically not necessary in the vast majority of these cases, and only needlessly increases our health care costs (these tests often cost several hundred dollars). In the vast majority of cases, antibody tests are all an adult needs. If a person cannot cope with the 6 month waiting period for antibody testing, counseling is often a better option than PCR testing.

There is a specific additional situation (other than those listed above) when the PCR test can be used for diagnostic purposes, as discussed in the paragraph below.

When are these tests recommended to help diagnose HIV?

There is a specific situation when viral load tests, antigen tests, and PCR tests are recommended to help diagnose HIV. This would be if a person has recently had a HIGH RISK exposure to a person KNOWN to have HIV (or KNOWN to be at high risk for HIV), AND the person is having symptoms consistent with Acute Viral Syndrome. In this specific situation, viral load tests, antigen tests, PCR tests, and antibody tests, are done together to determine if the symptoms are due to HIV or not. Other than this unique situation, using these tests for diagnostic purposes is not necessary. These tests are NOT designed to test people who are worried about symptoms, after having a possible exposure with someone whose HIV status is unknown!

Tests for HIV-2 and Group "O":

The HIV-2 virus is found almost exclusively in Western Africa, and in persons who have had sex, or shared needles, with West Africans. Because the HIV-2 virus is so rare outside of Western Africa, testing for this virus in persons without a direct West African connection is usually not necessary. The only routine testing for HIV-2 is in the blood supply (at least in the United States). The blood supply is tested for this virus to remove any risk (no matter how small) for this virus. However DO NOT donate blood to be tested for HIV-2. If you have been at a realistic risk of infection for HIV-2, have your doctor order this test for you.

The Group "O" strain of HIV-1 is EXTREMELY rare worldwide. In the rare instances where it has been found, it has most often been in West Africans, or persons with a direct West African connection. Even in Western Africa, this strain of HIV-1 is very rare. Present HIV-1 antibody tests will usually detect this rare strain, but not always. Because this strain is EXTREMELY rare, it would be EXTREMELY unlikely that you would be infected.

In summary:

Many persons have incorrectly assumed that I am against using these tests. On the contrary, these are very good tests, when they are used for their intended purposes! What I am against, is the misuse of these tests. The vast majority of people who have requested PCR tests, viral load tests, antigen tests, CD4 counts, etc. for diagnostic purposes, did not have a clinical need to take those tests, and most were at very low risk for HIV infection. Lab tests do not solve issues like fear, and guilt, and are not designed for that purpose. That is what counseling is for. Taking unnecessary tests is a waste of your time, the lab's time, and your doctor's time. Taking unnecessary tests is also a waste of your money, and needlessly increases healthcare costs, even if you pay for the tests yourself. If you have put yourself at a realistic risk for HIV, then by all means, take the antibody tests. Antibody tests are specifically designed for the routine testing of HIV in adults, are inexpensive, and are very accurate. If you have not put yourself at a realistic risk of infection, then save your money, as these tests are not necessary. "

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