CHEMISTRY (CHEM) SCREEN THE ELECTROLYTES KIDNEY FUNCTION TESTS LIVER FUNCTION TESTS OTHER BLOOD CHEMISTRY TESTS FOR MORE INFORMATION CHEMISTRY (CHEM) SCREEN A large part of your laboratory report is results of the chemistry screen. These tests measure various chemicals in your blood to see whether your body is working correctly. See Fact Sheet 121 for information on the Complete Blood Count and Fact Sheet 123 for information on blood glucose (sugar) and cholesterol tests. Laboratories have different "reference ranges" or normal values for the results of each test. Most lab reports show the normal range and highlight any test results outside the normal range. For more information on laboratory test results, see fact sheet 120 or MEDLINEplus online at https://www.medlineplus.gov/ The mineral calcium is a major component of bones and teeth. Calcium is also needed for nerves and muscles to work properly, and in chemical reactions in the cells. The body controls the amount of calcium in the blood. However, the amount of protein in the blood can affect calcium test results (see albumin). The most common cause of low calcium test results for people with HIV is low protein levels due to malnutrition or wasting. Abnormal calcium levels can indicate digestive problems. Phosphorus, like calcium, is a major component of bones. Low levels of phosphorus for a long period of time can cause damage to bones, nerves and muscles. High phosphate levels are most often due to kidney failure. Glucose is sugar, which is broken down in the cells to provide energy. See Fact Sheet 123 for more information on blood glucose tests. THE ELECTROLYTES The electrolytes are related to fluid balance in your cells. They are especially important if you become dehydrated or have kidney problems. Sodium levels indicate your balance of salt and water. They also are a sign of the functioning of your kidneys and adrenal glands. Abnormal blood sodium levels often indicate that blood volume is too low (due to dehydration) or too high. They can also occur when the heart is not pumping blood normally, or when the kidneys are not working properly. Potassium affects several major organs including the heart. Potassium levels rise in kidney failure, and may be abnormal due to vomiting or diarrhea. Chloride levels often go up and down along with sodium levels. This is because sodium chloride, or common salt, is a major component of blood. Bicarbonate or CO2 measures a buffer system in the blood. A normal CO2 level keeps the blood acidity at the correct level. A high level might be caused by high levels of lactic acid in the blood. KIDNEY FUNCTION TESTS The basic kidney function tests are blood urea nitrogen (BUN) and creatinine. Abnormal levels of phosphorus, sodium or uric acid can also be caused by kidney problems. Blood Urea Nitrogen (BUN) is nitrogen in the blood. This is a waste product that is normally removed by the kidneys in the urine. High BUN levels can be due to a high-protein diet, dehydration, or kidney or heart failure. Creatinine is a waste product of protein digestion and a measure of kidney function. High levels are usually due to kidney problems. Doctors use the creatinine level as most direct sign of how well the kidneys are removing waste products from the body. LIVER FUNCTION TESTS The lab tests called "liver function tests" actually measure the levels of enzymes found in the liver, heart, and muscles. Enzymes are proteins that cause or increase chemical reactions in living organisms. High enzyme levels can indicate liver damage caused by medications, alcohol, hepatitis, or recreational drug use. Different patterns of these enzymes – when some are elevated and others are normal – can help your doctor identify specific health problems. Laboratory tests include: ALT (alanine aminotransferase), formerly called serum glutamate pyruvate transaminase or SGPT) AST (aspartate aminotransferase), formerly called serum glutamic-oxaloacetic transaminase or SGOT) Bilirubin (a yellow fluid produced when red blood cells break down). Note: The antiviral drugs indinavir (Crixivan®) and atazanavir (Reyataz®) can increase bilirubin. Alkaline Phosphatase GGT (gamma glutamyl transpeptidase) LDH (lactic dehydrogenase, not the same as lactic acid) OTHER BLOOD CHEMISTRY TESTS Uric Acid comes from the breakdown of DNA (genetic material in the cells). It is normally removed by the kidneys. High levels of uric acid are fairly common. Very high levels can be caused when the kidneys are unable to remove uric acid from the blood or by leukemia or lymphoma. Albumin is the major protein in the blood. It maintains water balance in the cells, carries nutrients to the cells and removes waste products. Low albumin is generally a sign of nutrition problems. Because albumin carries so many substances in the blood, low albumin levels can cause incorrect low results for other laboratory tests, especially calcium or testosterone. Globulin (also called immunoglobulin) measures the protein in antibodies produced by the immune system. HIV infection causes an abnormally high level of globulin. Levels are usually reported for IgG and for IgA, Igd, IgE and IgM. Sedimentation Rate (Erythrocyte Sedimentation Rate) or Sed Rate measures how quickly red blood cells settle in a tube of blood. A high sed rate indicates some type of inflammation. However, the sed rate does not indicate whether the inflammation is long-term, like arthritis, or is due to the body fighting an infection. The C-Reactive Protein test or CRP is another general test of inflammation. It rises and falls faster than the Sed Rate. High levels of CRP may be a sign of increased risk of heart attack. FOR MORE INFORMATION See Lab Tests Online at https://www.labtestsonline.org/ source: The AIDS Infonet

HIV/AIDS Treatment Periodicals

[Note: On November 9, 2001, the U.S. Centers for Disease Control and Prevention issued two revised guidelines encouraging health care providers to routinely offer HIV testing more often. The goal is to increase the number of people who know their HIV status. These guidelines are available at: https://www.cdc.gov/hiv/pubs/guidelines.htm, or by calling 1-800-458-5231. [We had asked previously asked Bruce Mirken to write an introduction to HIV testing, including reliability of the tests today, oral HIV tests, rapid HIV tests, anonymous testing, the home test kit (which makes anonymous testing available in all states), and viral load testing to detect HIV in the "window period" before the immune system has produced antibodies, which standard HIV tests detect. JSJ] * * * * * HIV antibody testing has been with us since 1985. Testing technology has evolved considerably over the years, with a variety of new and improved tests coming into use, both in research and daily practice. Since determining one’s HIV status is the first step in treatment decisions, it is important to understand the tests being used today, including their limitations. The Basic Testing Procedure "The primary purpose of the test in 1985 was to screen the blood supply," recalls Steve Morin, director of the University of California San Francisco’s AIDS Policy Research Center. At the time there were no treatments available for HIV infection, and no one knew how likely it was that an HIV-infected person would get AIDS or how quickly it might happen. The only medical interventions available dealt with the opportunistic diseases that appeared once the immune system was weakened, so there was no pressing need for people to find out their HIV status. Still, it was clear that some who believed themselves at risk would want to know. And that, Morin notes, led to "a fear that people who wanted to know whether they were infected or not would go to donate blood in order to find out." To head off this possible threat to the blood supply, federal and state governments set up alternative test sites, where people could be tested without giving blood. Back then, the main public health value of HIV testing was "as a prevention tool," Morin says, "to counsel people… about not transmitting the virus to anyone else." That changed with the advent of antiretroviral therapy and prophylaxis (preventive treatment) aimed at preventing opportunistic infections. Over time, HIV testing became a gateway to treatment, as well as a prevention tool. Although there have been technological changes, HIV testing in the U.S. still follows the same basic testing procedure as in 1985: HIV infection is only considered confirmed after two tests have been done, a screening test and a confirmatory test. In a recent article for the University of California San Francisco’s HIV InSite (https://hivinsite.ucsf.edu), University of Maryland researcher Niel Constantine explains that "screening tests possess a high degree of sensitivity, whereas confirmatory assays have a high specificity. Tests with high sensitivity produce few false-negative results, whereas tests with high specificity produce few false-positive results." Because the screening tests can produce false positives, a second screening test is typically run on the same sample – in duplicate – with the confirmatory tests only run on samples that are repeatedly positive ("reactive" in lab parlance). The combination of the two types of tests produces results that are "highly accurate," Constantine notes, but technical errors are possible, and biological factors can occasionally produce problems. The most common screening test is the enzyme-linked immunosorbent assay (ELISA), sometimes called enzyme immunoassay (EIA). The most often used confirmatory test is the Western blot. Identical technology is used in tests for numerous illnesses, including Lyme disease, Constantine explains. Indeed, the immunological methods underlying these tests are so fundamental that Sally Liska, head of the city of San Francisco’s Public Health Laboratory, calls it "serology 101." The ELISA is used for initial screening because of both its high sensitivity and its practical advantages, Liska adds: "It’s a lot easier to do many specimens on an ELISA. It’s smaller volume, it’s less handling, it’s more automated." Over 40 different ELISA HIV test kits are available from various manufacturers, though only a fraction of these are licensed by the FDA – a requirement if they are to be used in the U.S. (a few tests are approved for research only). These tests use artificial HIV proteins that are able to capture antibodies to the virus. Once those antibodies are caught, Constantine explains, they "can be detected using other reagents that are usually coupled to an indicator such as a dye or enzyme that can produce color." The change in color is read by a machine. The Western blot is somewhat similar, but uses an electrical field that separates out the various components by their molecular weight. This allows identification of antibodies to specific viral antigens, which show up as identifiable "bands" on a strip of test paper. The Western blot, Liska says, "is a little more complicated to do… It’s more hands-on." Because it is less sensitive, she adds, it "should never be run by itself." Although the Western blot is the most common confirmatory test, others are sometime used, including the indirect fluorescent antibody assay (IFA) and the radioimmunoprecipitation assay (RIPA). "If performed and interpreted correctly, these extremely specific tests should not produce biologic false-positive results," Constantine writes. The "Window" Period Just After Infection One major drawback of antibody tests is the "window" period: the time it takes the body to produce antibodies after infection has begun. The standard tests for HIV do not detect the virus itself, but the antibodies that the body produces in response. During the period before the antibodies are produced, a person can be infected with HIV and can infect others, but still test negative on the HIV antibody test. For the first tests licensed, this window period ranged from six to 12 weeks, but improved technology has allowed the detection of lower levels of antibodies, making it possible to identify them earlier. "Currently

[Note: Part 1 of this article appeared in AIDS Treatment News #374, November 23, 2001.] Detecting Acute HIV Infection Shortly after getting infected with HIV, many patients have an acute (or “primary”) HIV infection, a period of flu-like illness with symptoms like fever and malaise that could be caused by influenza or many other diseases. Many scientists and physicians believe it is important to treat during acute this HIV infection (provided, of course, that it gets diagnosed then). But there are still questions remaining about treating acute infection.1,2 To confirm an acute HIV infection in symptomatic individuals with potential HIV risk factors, current guidelines2 recommend use of HIV RNA (viral load) tests. [The regular HIV antibody test will not detect acute HIV infection because the patient is still in the “window period” before antibodies have been produced.] False positives can occur with viral load tests, but a review of the data in the August, 1999 American Family Physician1 suggests it is usually possible to differentiate these from the real thing: “During the symptomatic phase of acute HIV infection, the viral RNA shows in excess of 50,000 copies per mL. Three instances of false-positive HIV-1 RNA tests have been reported; in each instance, however, the person was not having symptoms and the viral load [reported] was less than 2,000 copies per ml. The presence of high-titer HIV-1 RNA (more than 50,000 copies per mL) in the absence of HIV antibodies establishes diagnosis of acute HIV infection.” At present there is no viral load test approved by the FDA for the purpose of diagnosing HIV infection in individual patients. In September the FDA did approve a viral load test developed by National Genetics Institute for screening large pools of donated blood plasma. If viral load testing is not available, current treatment guidelines2 recommend testing for p24 antigen, a viral protein. In either case, the diagnosis should be confirmed by antibody testing once the window period has elapsed. “Detuned” ELISA A variation of standard antibody testing, presently approved in the U.S. only for research, is the sensitive/less sensitive or “detuned” ELISA. The detuned test takes advantage of the fact that antibody levels rise in a predictable pattern during roughly the first four to six months after infection, eventually reaching a plateau that often stays roughly constant for many years. Current ELISAs can detect relatively low levels of antibodies. The detuned testing approach involves taking samples that are confirmed HIV-positive by these tests, but then retesting them with a less sensitive, diluted ELISA. This less sensitive test can only detect antibodies at the higher levels achieved during the period six months or more after infection. Thus, the detuned approach distinguishes between recent and established infections, so it is a potentially valuable tool for epidemiologists trying to chart the pattern of new infections. It is not used in patient care at this time. Accuracy of Antibody Testing — and Denialist Arguments Constantine3 sums up the general consensus among experts and institutions such as the CDC when he says “The antibody tests are nearly 100 percent sensitive (unless a person is in the window period) and about 99 percent specific.” Such levels of accuracy have been documented in a number of studies, including periodic evaluations of commercially available test kits conducted by the World Health Organization. Still, AIDS denialists (the self-styled “AIDS dissidents” who claim that HIV is either harmless or doesn’t exist) continue to claim that HIV antibody tests are unreliable. Many of their arguments seem to derive from a series of articles written by Christine Johnson in the mid-1990s, several of which are available on denialist web sites.4,5,6 Johnson’s argument boils down to two key points: 1) HIV has never been properly isolated, so the HIV proteins used in the tests haven’t been proven to actually come from HIV, 2) Even if HIV is real, the proteins are not unique and cross-react with many other antigens, rendering a positive result meaningless. Johnson’s list of some 60 factors she describes as “known to cause false-positive HIV-antibody test results” turns up regularly in denialist literature. The claim that HIV has never been properly isolated, based on the writing of a group in Perth, Australia, is too technical and complex to examine thoroughly here. However, it is elegantly demolished in Michael Coon’s article, “HIV, AIDS and the Distortion of Science,” available on the AEGIS web site.7 In short, Coon argues that the Perth Group set up artificial, phony criteria for “proof” of HIV’s isolation that bear no relation to how virology works in the real world. The second argument, though, contains a grain of truth. Cross-reactions are possible, and a number of factors can, on occasion, produce false-positive HIV antibody test results. What Johnson fails to address in any detail is that such effects are typically transient and rare, affecting few individuals. For example, one well-known causes of false-positives Johnson lists is influenza vaccination. 8,9 But she neglects to mention that a key reference she cites described the phenomenon as “infrequent” and “of short duration,” while in another only 10 false-positives were found among 133,000 individuals who had flu shots prior to testing, with half of those reverting to negative within six months.9 Constantine adds, “I doubt very much that it has been firmly documented that 60 factors can interfere with antibody tests. In fact, it has been long sought to try and identify the causes of false positive results, and only a few have really been documented to consistently interfere (e.g. pregnancy, certain autoimmune diseases, some infectious diseases). However, even these do not consistently cause problems with the tests… There are very few false positives that can’t be resolved with further testing.” Consent, Anonymity, and Counseling (1) Anonymous Testing Prior to HIV, blood testing was considered a routine procedure, with such minimal dangers that formal informed consent was rarely required. But because HIV presented massive psychosocial risks, from employment discrimination to rejection by family and reduced access to health care, special procedures were widely adopted.10

999. Internet Bookmarks for AIDS A listing of over 750 web sites dealing with HIV/AIDS, divided into categories. [Revised: May 4, 2007] source: The AIDS Infonet

800. Nutrition A discussion of the role of good nutrition for people with HIV. [Revised: May 13, 2007] 801. Vitamins and Minerals A discussion of the role of vitamin and mineral supplementation for people with HIV. [Revised: April 26, 2007] 802. Exercise and HIV A discussion of the role of physical exercise for people with HIV. [Revised: April 12, 2007] 803. Smoking and HIV A discussion of the impact of smoking on HIV disease and antiretroviral treatment side effects. [Revised: April 12, 2007]   source: The AIDS Infonet

700. Alternative and Complementary Therapies A discussion of the use of alternative and complementary therapies by people with HIV, and a discussion of the challenges in researching these approaches. [Revised: April 26, 2007] 702. Ayurvedic Medicine A discussion of the use of Ayurvedic medicine for people with HIV. [Revised: September 5, 2006] 703. Chinese Acupuncture A discussion of the use of Chinese acupuncture for people with HIV. [Revised: May 13, 2007] 704. Chinese Herbalism A discussion of Chinese herbalism and how it is used by people with HIV. [Revised: May 13, 2007] 708. Native American Traditional Healing A description of Native American traditional healing related to HIV. [Revised: May 13, 2007] 722. Cats Claw (Uña de Gato) A discussion of the herb cats claw in relation to HIV infection. [Revised: May 13, 2007] 724. DHEA A discussion of the use of the hormone DHEA in relation to HIV infection. [Revised: May 13, 2007] 725. DNCB (Dinitrochlorobenzene) A description of the use of the chemical DNCB (dinitrochlorobenzene) by people with HIV. [Revised: April 26, 2007] 726. Echinacea A discussion of the use of the herb echinacea by people with HIV. [Revised: April 26, 2007] 727. Essiac A discussion of the use of the herbal tea Essiac by people with HIV. [Revised: June 25, 2007] 729. St. Johns Wort (Hypericin) A discussion of the use of the herb St. Johns Wort (hypericin) by people with HIV.’ [Revised: July 23, 2007] 731. Marijuana A description of the use of marijuana by people with HIV to alleviate side effects and increase appetite. [Revised: May 2, 2007] 735. Silymarin (Milk Thistle) A discussion of the use of the herb milk thistle (silymarin) by people with HIV. [Revised: April 26, 2007]   source: The AIDS Infonet

651. HIV and Kidney Disease A discussion of kidney disease in people with HIV, including risk factors and diagnostic tests [Revised: October 27, 2006] source: The AIDS Infonet

610. Women and HIV A description of special considerations for women with HIV, including transmission, symptoms, side effects, and treatment. [Revised: May 5, 2007] 611. Pregnancy and HIV A discussion of special considerations for women with HIV during pregnancy. How to protect the health of the mother and reduce the risk of infecting their newborn baby. [Revised: May 4, 2007] 612. Children and HIV A discussion of how children with HIV are different in terms of HIV disease and treatment. [Revised: December 30, 2006] 616. Older People and HIV An informational fact sheet on older people (over age 50) and HIV. [Revised: May 5, 2007]   The AIDS Infonet

Side Effects 550. Side Effects A discussion of the most common side effects of antiretroviral treatment, with links to other fact sheets for more information. Includes fatigue, anemia, digestive problems, lipodystrophy, peripheral neuropathy, mitochondrial toxicity, and osteoporosis. [Revised: April 26, 2007] 551. Fatigue A description of fatigue among people with HIV, its causes and treatment. [Revised: April 26, 2007] 552. Anemia A description of anemia among people with HIV, its causes and treatment. [Revised: April 26, 2007] 553. Body Shape Changes (Lipodystrophy) A description of lipodystrophy (changes in metabolism and body shape) in people with HIV, its risks, suspected causes and treatment. [Revised: September 12, 2006] 554. Diarrhea A description of diarrhea in people with HIV, its causes and treatment. [Revised: August 24, 2007] 555. Peripheral Neuropathy A description of peripheral neuropathy in people with HIV, its causes and treatment. [Revised: July 23, 2007] 556. Mitochondrial Toxicity A description of mitochondrial toxicity in people with HIV, its causes and treatment. [Revised: July 23, 2007] 557. Bone Problems A discussion of loss of bone mineral density associated with HIV and its treatment, including osteoporosis and avascular necrosis. [Revised: July 23, 2007] 558. Depression and HIV A description of depression in people with HIV and AIDS, its causes, symptoms, and treatment. [Revised: September 6, 2006]   source: The AIDS Infonet