But right about that time, a blood test revealed that Carrillo had elevated liver enzymes. He was diagnosed with Hepatitis C, but the medication he was prescribed made Carrillo's blood so thin that he had to discontinue taking it. His condition worsened, and in the fall of 2007, Carrillo's doctor said his liver would cease functioning in about a year.
"The doctor said there was nothing more they could do," Carrillo said. "He didn't give me any options."
Like Carrillo, many others with HIV are living decades after their diagnosis, thanks to the development in the mid-90s of a new class of AIDS drugs, which drastically slow the progression of the virus. But while the threat posed by infection has declined, the danger of organ failure has become more likely.
"As treatment has improved, patients are not dying of HIV complications but from liver disease and cirrhosis complications," says Dr. Nicholas N. Nissen, assistant surgical director of the Multi-Organ Transplant Program at Cedars-Sinai Medical Center's Center for Liver Diseases and Transplantation. "Individuals with HIV should know that, despite excellent control, liver disease and liver cancer are increasingly likely."
Carrillo, 46, had resigned himself to the idea of having a year to live, but his mother, Sandy, was unwilling to accept such a fate for her son. While scouring the Internet for information, she found a study involving liver transplantation for individuals with HIV. One of the study locations was Cedars-Sinai.
The medical center is participating in a National Institutes of Health-sponsored clinical trial to evaluate the safety and effectiveness of liver transplantation among HIV-positive patients. Cedars-Sinai is one of only 11 hospitals in the country and two in the state participating in the study. The other California facility, University of California San Francisco Medical Center, is also studying the effectiveness of kidney transplantation in HIV-positive patients.
"This is a tremendously important question," Nissen said. "Patients ill enough to be a candidate for liver transplantation are out of other options. This is the best and sometimes only option they have."
Nissen says that many transplant centers have been reluctant to perform transplants in HIV-positive patients with liver failure because little is known about how they fare afterwards. In addition, it had been assumed that the immune-suppressing medications required for an organ transplant would "allow HIV to run wild."
Patients who are part of the study have agreed to be monitored for effects of the transplant and immuno-suppression drugs for five years following their transplant. As with any liver transplant recipient, their status on the waiting list for an organ is based on a numerical score determined by medical tests.
"Liver transplantation is a well-established procedure," Nissen said. "We are not comparing two types of therapy, as is often done in a clinical trial. Rather, we are evaluating how these patients do when transplanted."
Patients admitted to the study must have a strong enough immune system and no severe infections or malignancies. Carrillo underwent a series of tests to assess his health status before being accepted to the study.
An earlier study published this year in The American Journal of Transplantation concluded that liver transplantation was "an option for selected HIV-infected patients cared for at centers with adequate expertise." However, it involved only 11 patients. The current, multicenter study will follow 125 liver transplant patients and publish findings next year.
The biggest challenge, Nissen says, is integrating the combination of medicines this group of patients requires after transplant. The combination includes those designed to prevent organ rejection along with medications addressing HIV and other recurrent disease. "It's not just the transplant itself, but the effect of medication on HIV.... Any change in medication would require involving [a team of] physicians."
Cedars-Sinai has assumed some risk by being part of the trial since the hospital's overall liver transplant results -- available online to the public -- could be negatively affected were the HIV positive group to show poor results.
Carrillo is glad the hospital was willing to take that risk. His condition had been deteriorating since he was accepted into the study in January. On Sept. 10, he received a new liver, and was discharged from the hospital a week later.
He says he has more energy and feels like "a whole new person."
"This has given me another 20 or 30 years that I didn't know I would have," Carrillo said. "My brother has two young children, and now I have hope of seeing them grow up."