Health Education AIDS Liaison, Toronto
CD4+ cells: What do they count for?
Testing … testing …
Rumblings of discontent among people diagnosed HIV positive have meant an increasing
reluctance to submit to the stress of T-cell
counting now that we are beginning to realise
how meaningless the practice is. Celia Farber,
journalist and AIDS commentator writes about
how T-cell counting affects the lives of
HIV positive people.
Disputing a Theory About AIDS Progression
Evidence suggests that a decrease in CD4 + T cells is not a death sentence
The Scientist 15[10]:17, May 14, 2001
The decline in the immune system function is held to be due to high titers of active virus causing increasing
infection of CD4 T-Lymphocyte cells. For years, CD4 T-cell count has been an unquestioned cornerstone that
guides clinical treatment. But, Louis J. Picker, associate director of the Vaccine and Gene Therapy Institute at
Oregon Health Sciences University in Portland, now says that using a more accurate 'flow cytometry assay'
measure of cell count shows : "There was no clear-cut association between viral load and the [numbers] of
these cells," suggesting that HIV-specific CD4+ T cell levels are not an accurate marker of disease progression.
Low CD4+ T-cell counts: A Variety of causes and their implications to HIV and AIDS
By Matt Irwin, MD
Abstract
: Low CD4+ T-cell counts (CD4 counts) are associated with a variety of conditions, including many viral infections, bacterial infections, parasitic infections, sepsis, tuberculosis, coccidioidomycosis, burns, trauma, intravenous injections of foreign proteins, malnutrition, over-exercising, pregnancy, normal daily variation, psychological stress, and social isolation. This paper presents a brief review of several studies documenting low CD4 counts in people who have these conditions. The low CD4 counts caused by some of these conditions often fall below 200 per cubic millimeter, which is the level needed to diagnose acquired immunodeficiency syndrome (AIDS) in someone who was previously positive for antibodies to the human immunodeficiency virus (HIV-positive). In addition to the diagnosis of AIDS, CD4 counts are regularly used to make treatment decisions, such as when to start antiretroviral medications and when to begin preventative antibiotics.
Because many of the conditions that cause low CD4 counts are common in people diagnosed HIV-positive, caution is advised regarding the use of CD4 counts to make treatment and diagnostic decisions. This is made more urgent since some of the conditions, like psychological stress, are greatly increased when people are told that their CD4 counts are low, which may compound the problem and cause the CD4 count to fall even furthur. Psychological stress and social isolation are also created by the diagnosis, HIV-positive, and by the diagnosis of AIDS, which may also affect the CD4 count. Finally, the widely accepted argument that HIV specifically targets CD4+ T-cells is also called into question, because it appears that low CD4 counts are a common reaction to many kinds of physical and psychological stressors. When several of these factors are combined, as is often the case in HIV and AIDS, extremely low CD4 counts may be a natural result.
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Researchers at the University of California at Los Angeles School of Medicine
found that 5% of healthy persons seeking life insurance had abnormal T4 cells
counts, and that "In a subgroup of patients, the low T-cell numbers or ratios
appear to be stable findings". They concluded: "In the absence of a history of
a specific infection or illness or major abnormalities on a physical
examination, it is not worthwhile to attempt to find a specific cause for the
abnormality of T- cell subsets...A uniform approach to this problem throughout
the medical community will help alleviate patients' anxiety and reduce the
concern of the insurance industry about this relatively common problem" (Rett
et al., 1988).
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For a review of AIDS-related T-cell counting read this excerpt from:
A CRITICAL ANALYSIS OF THE HIV-T4-CELL-AIDS HYPOTHESIS
Eleni Papadopulos-Eleopulos,1 Valendar F.Turner,2
John M. Papadimitriou,3 David Causer,1 Bruce Hedland-Thomas,1
& Barry Page1
1: Department of Medical Physics, 2: Department of Emergency
Medicine, Royal Perth Hospital, Perth, Western Australia; 3: Department
of Pathology, University of Western Australia.
Genetica 95: 5-24, 1995
Concerns about HIV/AIDS Testing and Measurement
HIV-positive people are some of the most poked, prodded, tested and measured in the world. Yet, surprisingly enough,
most of the tests and measurements are not nearly as accurate as is generally stated. This document from the Alberta Reappraising AIDS Society describes each of the tests used to diagnose or monitor HIV status followed be long lists of quotes from scientific journals. See section: CD4/CD8 Cell Counts
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