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The need for liver transplant in HIV-HCV co-infection
2 May 2012 - The widespread availability of potent combination therapy for HIV (commonly called ART or HAART) in Canada, Australia and Western Europe has generally led to dramatic declines in deaths from AIDS-related infections. In these countries and regions, a person who becomes HIV positive today and who is engaged in their care and treatment can expect to live a near-normal lifespan.
Co-morbidities
However, in HIV-positive people with co-existing conditions, particularly those involving substance use, additional steps will be necessary to increase lifespan, including the following:
- support for quitting smoking
- screening for and treatment of depression
- support for recovery from addiction
- screening for and treatment of viral hepatitis infections, such as hepatitis B and C viruses
- screening for and treatment of complications caused by human papilloma virus (HPV)
- vaccinations for hepatitis A and B viruses, and possibly HPV
Risks for viral hepatitis
Although deaths from AIDS-related infections have greatly decreased in high-income countries, serious illness and death from complications of hepatitis C virus (HCV) infection are rising among HIV-positive people. Today, this virus is commonly spread through the sharing of contaminated equipment used for substance use and by unprotected anal sex, particularly among gay and bisexual men who are HIV positive. Another source of HCV infection can be exposure to unsterilized equipment used for tattooing and body piercing. In high-income countries, HCV (and HIV) was once spread via exposure to contaminated blood and blood products. However, today the blood supply in high-income countries is safe.
Liver damage
HCV infects the liver. As the immune system tries to rid the liver of HCV, inflammation occurs and healthy tissue is replaced with useless scar tissue. As the liver is slowly destroyed, changes in the architecture of the liver occur and blood vessels struggle to supply this damaged organ with blood. The pressure within the liver's blood vessels rises, increasing the risk of bleeding within that organ and in the intestines. Fluid can accumulate in the abdomen and this buildup of fluid can become infected with bacteria. Also, the circulation of blood to the kidneys can be affected in some cases of chronic HCV infection, causing these organs to become dysfunctional. These unfavourable changes to the liver, intestines and kidneys result in the accumulation of waste products in the blood that affect the functioning of the brain. The risk of developing liver cancer also increases as liver damage accumulates.
Therefore, avoiding behaviours that increase the risk of HCV infection and, if at risk, being screened for HCV, are an important part of staying healthy.
Treatment
Treatment for HCV is a combination of three of the following drugs:
- the immune booster interferon-alpha (a once-weekly injection)
- the broad-spectrum antiviral drug ribavirin (taken orally twice a day)
- the anti-HCV drug boceprevir or telaprevir (taken orally every 8 hours)
In clinical trials, high rates of cure have been achieved in participants with HCV mono-infection who were treated with this triple therapy.
Clinical trials with these drugs are underway with HIV-HCV co-infected people, though caution must be used because of the possibility of interactions between some medicines used for HIV and those used for HCV treatment.
Liver transplant
In cases of severe liver damage caused by HCV or the presence of liver cancer, patients are usually very ill and need a liver transplant. Support for liver transplantation among co-infected people in North America has been mixed. Historically, part of the reason for this centres around the issue of immune suppression. In order for a transplant to be successful, the immune system of the person who received the liver must be suppressed otherwise the immune system would attack the new organ. Thus, in addition to HIV's negative impact on the immune system, there is the potential burden of added immunosuppression.
In the time before the widespread availability of ART, organ transplants were attempted in HIV-positive people. In general, HIV-positive people who received transplants in the pre-ART era appeared to have shortened survival. In the present era, doctors in the U.S. and Western Europe have gained experience conducting successful liver and kidney transplants in HIV-positive people. Moreover, results from small clinical trials have shown that liver transplants can successfully be done without lasting damage to the immune systems of people with HIV.
Now more surgeons need to gain experience with organ transplantation in HIV-positive people and transplant teams need more experience in selecting suitable co-infected patients for possible transplants and minimizing their time on waiting lists so that their survival can be improved.
In our next CATIE News bulletin , we report on a recent clinical trial of liver and kidney transplants in participants who were co-infected with HIV and HCV.
-Sean R. Hosein
REFERENCES:
- Vibert E, Duclos-Vallée JC, Ghigna MR, et al. Liver transplantation for hepatocellular carcinoma: the impact of human immunodeficiency virus infection. Hepatology . 2011 Feb;53(2):475-82.
- Heard I. Human papillomavirus, cancer and vaccination. Current Opinion in HIV/AIDS . 2011 Jul;6(4):297-302.
- Wilkin T, Lee JY, Lensing SY, et al. Safety and immunogenicity of the quadrivalent human papillomavirus vaccine in HIV-1-infected men. Journal of Infectious Diseases . 2010 Oct 15;202(8):1246-53.
- Stock PG, Barin B, Murphy B, et al. Outcomes of kidney transplantation in HIV-infected recipients. New England Journal of Medicine . 2010 Nov 18;363(21):2004-14.
- Coffin CS, Stock PG, Dove LM, et al. Virologic and clinical outcomes of hepatitis B virus infection in HIV-HBV coinfected transplant recipients. American Journal of Transplantation . 2010 May;10(5):1268-75.
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CATIE-News is written by Sean Hosein, with the collaboration of other
members of the Canadian AIDS Treatment Information Exchange, in Toronto.
From Canadian AIDS Treatment Information Exchange (CATIE). For more information visit CATIE's Information Network
at http://www.catie.ca
Source: CATIE: CANADIAN AIDS TREATMENT INFORMATION EXCHANGE
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