Increasingly, transplant surgeons must initiate a tough conversation: explaining to patients what it means to accept an organ from a person who died from a drug overdose or engaged in other risky behaviors.

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Organ donors who recently injected drugs, as well those who were incarcerated or had sex for drugs or money, are among a growing group of people classified as being at "increased risk" of an infectious disease such as hepatitis C or HIV.

But the label may not be doing patients any favors.

National organ transplant numbers show the United States Public Health Service's increased risk of infection label (PHS-IR) is associated with hundreds of available organs going unused each year. Despite the very low risk of disease transmission, patients in need are saying no to these organs.

It's a dilemma that's becoming common for transplant patients as the nation's opioid epidemic yields a tragic surge in organ donors. Surgeons also face a quandary in explaining how much risk an increased-risk label actually presents to their patients.

Better guidance is needed for surgeons and transplant team members who walk this fine line every day, says Daniel Kaul, M.D., director of the Transplant Infectious Disease Service at Michigan Medicine.

Untapped potential

One in 5 deceased organ donors in the U.S. is identified as increased risk.

For a study published in Transplantation, Kaul led an analysis of Organ Procurement and Transplantation Network (OPTN) data showing organs labeled as increased risk are 7 percent less likely to be used than organs without the label.

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Increased-risk organs are viable and high-quality. They often come from young, otherwise healthy donors, but perceptions about their tainted past can lead to the organs being thrown out.

"Overall utilization was less despite the extraordinarily low risk of disease transmission," says Kaul, a professor of internal medicine at the University of Michigan. "The organ may have gone to the next person on the transplant waiting list, but it might not have been used at all."

Also troubling, utilization rates of PHS-IR organs varied dramatically by geography. Depending on the donation service area, transplantation of available adult kidneys from increased-risk donors ranged from 20 to 100 percent, the analysis found.

In other words, hospitals and organ procurement groups in some parts of the country use these organs as often as non-PHS-IR organs, while other service areas rarely use them.

"What that tells us is there may be a different understanding of true risk associated with this label — from one center to another and even within a center, from one organ specialty to another," Kaul says.

A widening gap

All organs identified as increased risk were less likely to be used with the exception of livers, for which transplant rates were nearly identical.

A possible explanation? Patients with liver failure may be too sick to say no.

An available liver is offered to the sickest person on the waitlist in a nearby area. Those who turn it down may not survive until another offer, or they may get so close to dying that they are taken off the waitlist.

By comparison, a patient needing a kidney may continue dialysis and wait for another organ.

There's also the chance that liver specialists are more comfortable discussing the risk of transmitting viral diseases such as hepatitis, Kaul says.

If the increased-risk label did not exist, an estimated 313 more transplants would be performed in the United States each year, according to the study.

Co-authored by Michael Volk, M.D., a former U-M physician now practicing in Loma Linda, California, and others, the study was published in a special issue of Transplantation that looked at reducing organ discard and maximizing organ availability.

As Kaul solemnly explains: "The tragedy of someone dying while waiting for an organ is a daily occurrence."

Researchers analyzed criteria of donors from 2010 to 2013. The rate of nonutilization of increased-risk organs, the authors write, is likely now even higher because of a 2015 change to the PHS-IR criteria. Combined with the opioid epidemic, the change resulted in an increase in the proportion of organs with this label from 12 percent to 20 percent.

Favorable odds

For most patients with end-stage organ failure, the immediate risk of dying is greater than the risk of getting an organ with an infection.

SEE ALSO: For Pediatric Transplant Patients, Adherence is Key

After rigorous screening, the risk of HIV or hepatitis C transmission from organ donation is low, at less than 1 percent — much less, for example, than the lifetime chances of dying in a motor vehicle accident.

But with little guidance about magnitude of risk, the stigma surrounding drug addiction can lead someone to turn down an organ that could save his or her life.

As of early October, about 116,500 Americans are waiting for an organ transplant.

Donors' blood is tested for common viruses before they are approved for transplantation. Nucleic acid testing detects viral genetic code harboring in the blood, but testing is not foolproof. If the donor caught an infection in the last week before death, there may not be enough RNA or DNA to be picked up.

Because of this slim risk — and for transparency's sake — transplant centers are required to get informed consent from patients willing to accept organs labeled as increased risk.

The willingness of a patient to accept them can depend on what they understand about risk and benefit. At Michigan Medicine, teams plan talks about increased-risk organs well before they might be offered to a patient.

"Although it's unlikely that the PHS designation will be eliminated, the transplant community could partially address the (utilization) problem through better patient and provider education," Kaul says.

OPTN and United Network for Organ Sharing asked for public comment this year as the groups develop guidance and training programs to help transplant centers counsel patients about the kind of organ they could receive — and, just as crucial, to ensure fewer available organs go to waste.