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AIDS/HIV
General Description
Acquired
immune deficiency syndrome (AIDS) is a disease that acts by lowering the
victims immunity, allowing secondary, unrelated infections to produce fatal
symptoms.
In 1983, researchers in France and the United States isolated the virus
that produces AIDS. This virus is known as the human immunodeficiency virus
(HIV).
Causes
HIV
causes depression in immunity by primarily affecting T-cells, which are
responsible for the bodys ability to defend itself against foreign organisms
(acquired immunity).
HIV appears to preferentially target helper T cells over other cells in
the body, although it has been shown to also be capable of attacking other
T cells and monocytes as well. Once it enters the body, it initially infects
helper T cells, causing flu-like symptoms that last for several weeks. The
virus then enters a dormant period which can range from 6 months to 10 years.
Following this dormant phase, HIV begins its reproductive phase. The virus
is released and invades other helper T cells, destroying them to produce
new viruses. This reproductive cycle is capable of destroying 60 - 90% of
the helper T cells in the body within several months. The result of helper
T-cell destruction is a suppression of cell-mediated immunity.
Once immunity has been suppressed, infectious agents take advantage of the
opportunity to cause secondary diseases. The opportunistic pathogens cause
many of the diseases which are used to diagnose AIDS: pneumonia from Pneumocystis
carinii, a type of skin cancer called Kaposis sarcoma, a liver disease called
hepatitis B, a systemic bacterial infection know as toxoplasmosis, a loss
of weight caused by chromic diarrheas known as HIV wasting syndrome, and
a degeneration of functional brain tissue called AIDS dementia. These secondary
diseases are the usual causes of death among AIDS sufferers.
At Risk
Initially,
AIDS was primarily confined to certain population sub-sets with high risk
for interchanging blood or other HIV-infected bodily fluids. Two groups
in particular, homosexual males and intravenous drug users, were at highest
risk.
Today, the prevalence of HIV has made caution the by-word for all individuals
exposed to blood or other bodily fluids. Stringent pre-testing and handling
precautions are indicated because the ultimate symptoms produced by HIV
which ultimately lead to AIDS can take several years to develop. There are
potentially many individuals who are unaware that they are HIV positive.
Prevention and Management
General:
At
the present time, there is no vaccine or drug to prevent AIDS. The best
way to reduce the risk of HIV exposure is to reduce or eliminate exposure
to potentially infected blood.
Sexual transmission of HIV, which is the most common mode of infection,
can be prevented by use of barriers such as latex condoms.
Health care professionals are well aware of the precautions that must be
taken whenever blood is handled. The best course is to assume that the blood
is HIV positive, and to take appropriate measures, such as latex gloves,
gowns, and eye protections, to prevent exposure.
Advanced cases of AIDS are accompanied by a general wasting of the body
(AIDS wasting syndrome). Many individuals with AIDS also have deficiencies
in many vitamins and minerals.
Nutrition and nutritional status can have profound effects on immune functions.1
Some AIDS sufferers have shown temporary improvement in their symptoms when
put on a strict nutritional regimen which also included vitamin supplements.2,3
Recent evidence also suggests that HIV infected individuals are under chronic
oxidative stress which may contribute to many aspects of the pathogenesis
of AIDS.4,5 This has lead to the suggestion that the progression of AIDS
may be retarded by supplementints natural antioxidant defenses.6 However,
well controlled prospective clinical trials of the efficacy of antioxidants
for AIDS remain to be performed.
Cognitive and hematopoietic dysfunctions of some AIDS patients is reversed
by vitamin B-12 therapy.7
Healthier Lifestyles Product Recommendations
Usana Proflavanol or Usana Prflavanol 90
Abstracts
Liang B, Chung S, Araghiniknam M, Lane LC, Watson RR. Vitamins and immunomodulation in AIDS. Nutrition 1996 12(1):1-7. Acquired immune deficiency syndrome (AIDS) is a clinical disorder caused by a retrovirus infection and represents the end point in a progressive sequence of immunosuppressive changes. Vitamins can enhance disease resistance in animals and humans. As such they are important co-factors in optimal functioning of the immune systems. In this article, the immunological and nutritional modifications caused by AIDS are summarized. The effects of murine and human retrovirus infection on vitamin status are analyzed as co-factors in the development of severe immune dysfunction, AIDS. The properties of immunoenhancing antioxidative vitamins, vitamin A, B6, B12, C, E, and beta-carotene, which are frequently low in AIDS patients, are evaluated relative to the development of immunodeficiency during retrovirus infection. Vitamin A, E, and B12 deficiency accelerated the development of AIDS with low T cells, whereas their normalization retarded the development of immune dysfunction. The interactions between these vitamins and the immune system in human AIDS patients and animal models of AIDS are reviewed. Our purpose is to provide data on how retrovirus infection can cause nutritional deficiencies that accentuate immune damage and to evaluate the potential therapeutic role of vitamins in the treatment of immune dysfunctions in AIDS patients.
Pace GW, Leaf CD. The role of oxidative stress in HIV disease. Free Radic Biol Med 1995 19(4):523-8. Evidence has accumulated suggesting that HIV-infected patients are under chronic oxidative stress. Perturbations to the antioxidant defense system, including changes in levels of ascorbic acid, tocopherols, carotenoids, selenium, superoxide dismutase, and glutathione, have been observed in various tissues of these patients. Elevated serum levels of hydroperoxides and malondialdehyde also have been noted and are indicative of oxidative stress during HIV infection. Indications of oxidative stress are observed in asymptomatic HIV-infected patients early in the course of the disease. Oxidative stress may contribute to several aspects of HIV disease pathogenesis, including viral replication, inflammatory response, decreased immune cell proliferation, loss of immune function, apoptosis, chronic weight loss, and increased sensitivity to drug toxicities. Glutathione may play a role in these processes, and thus, agents that replete glutathione may offer a promising treatment for HIV-infected patients. Clinical studies are underway to evaluate the efficacy of the glutathione-repleting agents, L-2-oxothiazolidine-4-carboxylic acid (OTC) and N-acetylcysteine (NAC), in HIV-infected patients.
References
1
Harbige, LS. Nutrition and immunity with emphasis on infection and autoimmune
disease. Nutr. Health, 10(4):285-312, 1996
2 Liang, B, S Chung, M Araghiniknam, LC Lane and RR Watson. Vitamins and
immunomodulation in AIDS. Nutrition, 12(1):1-7, 1996.
3 Chlebowski, RT, G Beall, L Lillington, EW Richards, BC Abbruzzese, MA
McCamish and FO Cope. Nutritional intervention in the course of HIV disease.
Nutrition, 11(2 Suppl):250-4, 1995.
4 Pace, GW and CD Leaf. The role of oxidative stress in HIV disease. Free
Radic Biol Med, 19(4):523-8, 1995.
5 Schwarz, KB. Oxidative stress during viral infection: a review. Free Radic
Ciol Med, 21(5):641-9, 1996
6 Segal-Isaacson, AE and CJ Rand. Antioxidant supplementation in HIV/AIDS.
Nurse Pract, 20(7):11-4, 1995.
7 Herbert, V, W Fong, V Gulle, TS Kasdan. Low holo-transcobalamin II is
the earliest serum marker for subnormal vitamin B-12 (cobalamin) absorption
in patients with AIDS. Am J Hematol. 34:132-139. 1990.
Information provided by Usana Health Sciences (www.usana.com)