Antiviral therapy
Current HAART options are combinations (or "cocktails") consisting of at least three medications belonging to at least two types, or "classes," of antiretroviral agents. Initially treatment is typically a non-nucleoside reverse transcriptase inhibitor (NNRTI) plus twonucleoside analogue reverse transcriptase inhibitors (NRTIs). Typical NRTIs include: zidovudine (AZT) or tenofovir (TDF) andlamivudine (3TC) or emtricitabine (FTC). Combinations of agents which include a protease inhibitors (PI) are used if the above regime loses effectiveness.
When to start antiretroviral therapy is subject to debate. Both the World Health Organization, European guidelines and the United States recommends antiretrovirals in all adolescents, adults and pregnant women with a CD4 count less than 350/uL or those with symptoms regardless of CD4 count. This is supported by the fact that beginning treatment at this level reduces the risk of death. The United States in addition recommends them for all HIV-infected people regardless of CD4 count or symptoms, however makes this recommendation with less confidence for those with higher counts.While the WHO also recommends treatment in those who are co-infected with tuberculosis and those with chronic active hepatitis B. Once treatment is begun it is recommended that it is continued without breaks or "holidays". Many people are diagnosed only after the moment treatment ideally should have begun.The desired outcome of treatment is a long term plasma HIV-RNA count below 50 copies/mL. Levels to determine if treatment is effective are initially recommended after four weeks and once levels fall below 50 copies/mL checks every three to six months are typically adequate. Inadequate control is deemed to be greater than 400 copies/mL. Based on these criteria treatment is effective in more than 95% of people during the first year.
Benefits of treatment include a decreased risk of progression to AIDS and a decreased risk of death. In the developing world treatment also improves physical and mental health. With treatment there is a 70% reduced risk of acquiring tuberculosis. Additional benefits include a decreased risk of transmission of the disease to sexual partners and a decrease in mother-to-child transmission. The effectiveness of treatment depends to a large part on compliance.[14] Reasons for non-adherence include: poor access to medical care, inadequate social supports, mental illness and drug abuse. As well the complexity of treatment regimens (due to pill numbers and dosing frequency) andadverse effects may create intentional non-adherence. Adherence is however just as good in low income as high income countries.
Specific adverse events are related to the agent taken. Some relatively common ones include: lipodystrophy syndrome, dyslipidemia, and diabetes mellitus especially with protease inhibitors. Other common symptoms include: diarrhea, and an increased risk of cardiovascular disease. Adverse effects are however less with some of the newer recommended treatments. Cost may be an issue with some medications being expensive however as of 2010, 47% of those who needed them were taking them in low and middle income countries. Certain medications may be associated with birth defects and thus not suitable for women hoping to have children.
Treatment recommendations for children are slightly different from those for adults. In the developing world, as of 2010, 23% of children who were in need of treatment had access. Both the World Health Organization and the United States recommend treatment for all children less than twelve months of age. The United States recommends in those between one year and five years of age treatment in those with HIV RNA counts of greater than 100,000 copies/mL, and in those more than five years treatments when CD4 counts are less than 500/ul.
Opportunistic infections
Measures to prevent opportunistic infections are effective in many people with HIV/AIDS. Treatment with antivirals often improves current, as well as decreases the risk of future, opportunistic infections. Vaccination against hepatitis A and B is advised for all people at risk of HIV before they become infected however may also be given after infection. Trimethoprim/sulfamethoxazole prophylaxis between four to six weeks of age and finishing breastfeeding in infants born to HIV positive mothers is recommended in resource limited settings. It is also recommended to prevent PCP when peoples' CD4 count is below 200 cells/uL and in those who have or have previously had PCP. People with substantial immunosuppression are also advised to receive prophylactic therapy for toxoplasmosis and Cryptococcus meningitis. Appropriate preventive measures have reduced the rate of these infections by 50% between 1992 and 1997.
Alternative medicine
In the US, approximately 60% of people with HIV use various forms of complementary or alternative medicine. The effectiveness of most of these therapies however has not been established. With respect to dietary advice and AIDS some evidence has shown a benefit from micronutrient supplements. Evidence for supplementation with seleniumis mixed with some tentative evidence of benefit. There is some evidence that vitamin A supplementation in children reduces mortality and improves growth. In Africa in nutritionally compromised pregnant and lactating women a multivitamin supplementation has improved outcomes for both mothers and children. Dietary intake of micronutrients at RDA levels by HIV-infected adults is recommended by the World Health Organization. The WHO further states that several studies indicate that supplementation of vitamin A, zinc, and iron can produce adverse effects in HIV positive adults. There is not enough evidence to support the use of herbal medicines.
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