HIV Weekly - April 3rd 2007

A round-up of the latest HIV news, for people living with HIV in the UK and beyond.

Circumcision

In Africa and Asia, men who are circumcised have a lower rate of HIV infection than men who are uncircumcised. The under-side of the foreskin contains cells easily infected by HIV, and the presence of the foreskin may also make it easier to catch sexually transmitted infections, especially those that cause ulcers.

Several large trials have now taken place in Africa to investigate whether offering circumcision to young, sexually active men results in a reduced risk of becoming infected with HIV for those men.

Circumcision appears to reduce the risk of HIV infection by about 60%, making it an important way of preventing HIV infection in countries where circumcision is not currently practiced and where HIV is already widespread.

Last week the World Health Organization and UNAIDS recommended that governments should consider whether to begin promoting circumcision as an additional HIV prevention measure. They stress that it should be offered in addition to promoting condom use, partner reduction and delaying the age at which sexual activity begins.

However, even before governments begin promoting circumcision, there are reports that men are coming forward to be circumcised in some African countries in growing numbers.

There are several concerns about the growing popularity of circumcision.

One is to do with the safety of the procedure. Badly done, circumcision can result in serious scars, wound infections, extensive bleeding and inflammation. Circumcision carried out by a doctor or a nurse who has been trained properly, using sterile instruments, has a low rate of complications, and the wounds generally heal within a month or so.

But circumcision carried out by untrained people, or people using unclean instruments, may result in a much higher rate of serious complications.

Another concern is that men who are circumcised will assume that they no longer need to use condoms, and will increase their sexual activity because they feel less vulnerable to HIV infection.

Research from Kenya suggests that men who are circumcised do not increase their sexual activity.

However, it’s still not known whether circumcision is worthwhile for men who have sex with men, or for heterosexual men in countries with low HIV prevalence.

It’s also unclear whether heterosexual HIV-positive men who get circumcised subsequently have a lower risk of passing on HIV to their female partners.

Hepatitis B

Hepatitis B is a viral infection that can cause liver damage, including liver cancer, if it is not treated. It is a blood-borne infection, so it can be passed on through sharing needles, through unclean medical instruments and through untested blood. In some parts of the world, such as Asia, coinfection with HIV and hepatitis B is common.

People who are infected with both HIV and hepatitis B need specialised treatment. This includes making sure that they are receiving drugs that will treat both hepatitis B and HIV and HIV at the same time.

However, a study at a large hospital in Texas has shown that only 16% had their hepatitis B virus levels checked before starting antiretroviral treatment. Two-thirds of coinfected patients did not have their levels of hepatitis B virus checked during the first year of antiretroviral treatment. This may be because there are no guidelines in the United States for treatment of people with HIV and hepatitis coinfections.

In the United Kingdom, where guidelines have existed for several years, doctors are recommended to test hepatitis B viral DNA levels in addition to looking at markers of liver damage in the blood. HBV DNA levels may provide useful information about whether it is necessary to use drugs that are also active against hepatitis B when planning antiretroviral therapy.

Tenofovir and 3TC (lamivudine) or FTC (emtricitabine) are active against both viruses. It is recommended that people with HIV and hepatitis B coinfection should receive tenofovir and either FTC or 3TC as their first-line treatment. 3TC or FTC should not given without tenofovir in case hepatitis B virus develops resistance to it.

Hepatitis C

Hepatitis C, a viral infection unrelated to hepatitis B, is also a bloodborne infection. Coinfection with HIV and hepatitis C is common in people who caught HIV through injecting drug use.

Like HIV, hepatitis C can also be passed on from mother to child. A large review of all the studies which have looked at the likelihood of mother to child HIV transmission has now concluded that mothers with HIV and hepatitis C coinfection are twice as likely to pass hepatitis C to their babies as women who have hepatitis C alone, even if they do not have detectable levels of hepatitis C virus in their blood.

Coinfected women with detectable hepatitis C virus in their blood were three times as likely to pass on hepatitis C when compared to women who have hepatitis C alone.

Green tea

Green tea is becoming a popular alternative to tea and coffee, not least for its advertised ability to raise the metabolic rate slightly and so assist in weight loss.

But green tea also has other properties which medical research is beginning to take an interest in. It has been shown to protect against tumour development, it has anti-bacterial properties, and now research carried out in the UK shows that it may have anti-HIV properties too.

The study tested the effect of a chemical in green tea called a flavonoid on HIV’s ability to bind onto human immune system cells called CD4 cells. Flavonoids are chemicals found in some foodstuffs, and they are a hot area of research at the moment. Flavonoids in red wine are thought to protect against heart disease at modest levels of consumption, and cocoa beans also contain flavonoids that might have similar effects.

The recent study on green tea and HIV found that when CD4 cells were exposed to the flavonoid in the test tube, it was much more difficult for HIV to bind onto the CD4 receptor because the flavonoid blocked the binding site very accurately.

The researchers calculated that the effect might be achieved with a daily consumption of two to three cups of green tea.

The reduction in binding was quite small, and it’s still not possible to say how much regular green tea consumption might protect against the progression of HIV disease. Further research is already underway to learn more about its effects and how it can be used in HIV treatment.

D4T dose

Stavudine, also known as d4T (Zerit), is a nucleoside analogue drug used in HIV treatment alongside two other drugs. It is frequently used as part of a fixed dose triple drug combination in resource-limited settings, but in Europe and North America d4T is no longer recommended for first-line treatment due to the high rate of side-effects caused by the drug.

The most frequent side-effects are peripheral neuropathy (nerve damage in feet and legs) and lipoatrophy (fat loss in the face and limbs). Another less frequent but much more dangerous side-effect is lactic acidosis, a build-up of lactic acid in the bloodstream that can rapidly lead to death if d4T treatment isn’t stopped.

Recently several large studies in Africa have reported very high rates of peripheral neuropathy in people treated with d4T.

These findings have led to the suggestion that the dose of d4T should be reduced. The current recommended dose for adults weighing more than 60kg is 40mg twice daily, but a review of clinical trials in which a lower dose was used has now shown that 30mg twice daily is just as effective, and may cause less peripheral neuropathy and other side-effects.

In adults who weigh less than 60kg a dose reduction from 30mg to 20mg twice daily may be needed.

Anal screening

Anal cancer is much more common among men who have sex with men than the rest of the population, and most frequently found in men who are HIV-positive.

Human papilloma virus (HPV), the cause of genital and anal warts is the underlying cause of anal cancer, and infection with HPV is widespread amongst gay men in general, and is particularly high amongst HIV-positive gay men. Infection with HPV in the anus has also been associated with the development of anal cancer in HIV-positive women.

Anal cancer develops as a result of cell changes in the anal tissue. Before cancerous cells are detected it may be possible to see changes called dysplasia in the anal tissue.

Some HIV clinics are looking at the value of regularly screening individuals with anal HPV for precancerous cells. This involves using a test very similar to the PAP (Papanicolaou) smear used to detect pre-cancerous cervical cells in women. Cells are scraped from the lining of the anus (which can be uncomfortable), and then examined for signs of abnormalities.

Anal PAP smears are not 100% accurate. The anus can be examined in more detail using a magnifying instrument during a procedure called an anoscopy. During this procedure small tissue samples from the anus can be removed – biopsied – and examined under a microscope to see if potentially cancerous changes to cells have occurred.

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