Hahnemann University Hospital last week became the second transplant center in the nation to receive permission to use organs from HIV-positive donors.

The organs would be given only to patients who also are HIV-positive and have agreed to accept them. The transplants will be part of research that will carefully monitor both the transplant and the potentially deadly disease.

Johns Hopkins Hospital in Baltimore announced last month that it would be the first to offer HIV-positive organs to HIV-positive patients on its waiting list. The advantage of such transplants is that they might reduce waiting times for HIV-positive patients and also free up other organs for patients who don't have the immune-weakening virus.

The new approach was made possible by the HIV Organ Policy Equity (HOPE) Act of 2013. Before that, it was illegal to transplant organs from people with HIV. The ban was enacted when the blood-borne virus was considered a death sentence, but now that it is so much more manageable, people who are infected often die of something else.

The Philadelphia hospital has now received permission from the United Network for Organ Sharing (UNOS) to begin what are called HIV-positive to HIV-positive liver and kidney transplants. Doctors expect that most of the transplanted organs will be kidneys and that the first case will occur this year. The hospital currently has 45 HIV-positive patients either on its waiting list for kidneys or being evaluated for transplants.

David Reich, a surgeon who heads Hahnemann's transplant program, said the transplant team enjoys the challenge of working with HIV-positive patients.

"What's gratifying for many caregivers is to make something possible to help people that wasn't safely possible yesterday," he said.

Johns Hopkins researchers, who lobbied for the law, estimate there could be 500 to 600 HIV-positive organ donors a year. They have yet to do one of the new transplants.

Penn Medicine, which has the region's largest transplant program, said it, too, plans to do transplants from HIV-positive donors to HIV-positive recipients, but is still establishing protocols. "As always, the safety of our patients and staff is our highest priority," said Susan Phillips, senior vice president for public affairs.

According to UNOS, 218 HIV-positive patients received transplanted kidneys in 2015. A spokeswoman said that is likely an undercount.

Alden Doyle, a nephrologist at Hahnemann, said the hospital began allowing HIV-positive patients to get transplants in 2002, about the same time as other centers around the country. Hahnemann has since done 111 transplants in HIV-positive patients, he said, giving it far more experience with that patient population than most hospitals.

Results are similar for patients with and without the virus when donors are virus-free. Doyle said South Africa is the only country that has used organs from HIV-positive donors. The numbers are small, he said, but results are encouraging.

A study of 27 South African patients found that 84 percent were alive three years after their transplants. According to UNOS, the three-year survival rate for people who receive kidneys from donors without HIV is about 88 percent.

Last year, 17,878 patients received kidney transplants in the United States. More than 4,200 died while waiting for a transplant.

Doyle said it has taken several years for experts to create protocols for using organs from HIV-positive donors. The procedures must also be approved by each hospital's Institutional Review Board, a group that oversees research.

Doyle said there are several subtypes of HIV. Doctors had been concerned that HIV patients might not fare as well if they received an organ from a donor with a different subtype of the virus. That has not been a problem so far in South Africa, he said.

Reich said the hospital will choose donors "very, very carefully." He said recipients tend to do better when they have not been on dialysis for a long time prior to their transplants.

Because there are now only two hospitals willing to accept HIV-positive organs, Johns Hopkins and Hahnemann will be the only ones competing for such organs from throughout the country. "That places patients on our list at exceptional access to kidneys," Doyle said.

You might think that patients with an immune-system disease would not do well with transplants, which require patients to take immune-suppressing drugs to prevent organ rejection. However, Doyle said modern HIV drugs make it possible to control the virus even while preventing rejection.

Reich said the new law has another benefit. It allows people with HIV to help others. "For that community to be able to give back . . . is incredibly important," he said.