Doctors Could Soon Be Performing Transplants Using Organs Infected With HIV
The organs would only be transplanted into people who are already HIV-positive, not people who don't have the infection. But that doesn't mean the new organ can't make them sicker.
These transplants could save thousands of lives, but there are serious complications that could arise that need to be better studied.
Impact of infected transplants
Currently, doctors aren't allowed to transplant otherwise-healthy organs from people infected with HIV, other infections, active cancer, or if the organ to be transplanted is too damaged at the time of the person's death.
Legislation to change this rule has already passed the Senate (way back in June) and was just approved by the House on Nov. 12. The bill is now on its way to the president for final approval, according to an article in Nature. The bill - called the HIV Organ Policy Equity Act - would also require more scientific study on these HIV-positive transplants so we can better understand the potential consequences.
Of course only people already infected with HIV would be eligible to receive an organ from an HIV-positive donor - a "positive to positive" transplant. According to the united network of organ sharing, almost 121,000 people are on the waiting list for organ transplants - many of them HIV-positive - so this new legislation could help curb organ demand.
In fact, a study in the American Journal of Transplantation from 2011 estimates this bill would allow for 500 to 600 additional organ donations every year. Advances in treatment mean that people with HIV are living much longer, healthier lives, but many of them are also infected with hepatitis C - a disease that ultimately requires a liver transplant.
However, there are serious concerns about the consequences these positive-to-positive transplants could have. There are several different strains of HIV so it may be possible to "superinfect" an HIV patient by giving them an organ infected with a different strain - especially if that strain is resistant to HIV drugs.
Tricky transplants
Regular organ transplants are already tricky and patients have to take drugs that lower their immune system defenses to make sure their bodies won't reject the new organ. But HIV attacks the immune system, so many people infected with HIV take drugs designed to boost their immune system. Scientists don't know how these two drugs would interact and there is concern that the organ rejection rate could be very high.
But positive-to-positive transplants are looking promising. Elmi Muller from the University of Cape Town has performed 26 of these positive-to-positive transplants in South Africa - a country with one of the highest HIV rates (see map below).
A study led by Peter Stock from the University of California, San Francisco, published in the New England Journal of Medicine in 2011, examined 150 kidney transplants among HIV-positive patients in the U.S. and found that 31% of the transplants were rejected after one year, and 41% of the transplants were rejected after three years. The rejection rate of normal, healthy, kidney transplants is much lower: The Scientific Registry of Transplant Recipients estimates that only around 6% to 12% of normal, healthy, kidney transplants fail after one year.
The scientists write in the paper that "the unexpectedly high rejection rates are of serious concern and indicate the need for better immunotherapy."
It seems clear that much more research is needed to determine how safe positive-to-positive transplants are. If the bill is signed into law, the Organ Procurement and Transplantation Network will have to develop a set of guidelines before any transplants are performed.