Use of Kidneys From High-Risk Donors Drops
FORT LAUDERDALE, Fla.—A single transmission of HIV via transplantation may have resulted in a decline in the use of high-risk donor (HRD) kidneys, according to new data presented here at the American Society of Transplant Surgeons 10th Annual State of the Art Winter Symposium.
In November 2007, four organ recipients acquired HIV from a high-risk donor infected with the virus. It was the first time such transmission had occurred since 1985, when three transplant recipients acquired HIV via transplantation.
HRDs are deceased donors who have a risk factor for HIV infection, such as injection drug use. All donors are tested for common viruses, but if an infection is acquired just before death—an interval called the window period—the test will be negative and the infection will be unknowingly transmitted to the patient.
Researchers at Johns Hopkins School of Medicine in Baltimore compared HRD utilization in a pre-transmission period (July 1, 2006 to June 30, 2007) and a post-transmission period (January 1, 2008 to December 31, 2008) using the United Network for Organ Sharing database. They found that 816 HRD kidneys were transplanted in the pre-transmission period compared with 740 in the post-transmission period. This drop in HRD organ utilization occurred despite a rise in the total number of kidney transplants performed nationally.
“We performed a survey of 422 transplant surgeons nationally and we found that about one-third of them changed their practice in response to this event. The most common change was to decrease the use of high-risk donors,” said study investigator Lauren Kucirka, MS, an epidemiologist who presented study findings.
In the pre-transmission period, HRDs were equally likely to be used locally than non-HRDs. In the post-transmission period, however, HRDs were 23% less likely to be used locally, according to the investigators. Moreover, the percent of HRDs transplanted at organ procurement organizations (OPOs) that performed HIV nucleic acid testing (NAT) rose from 67% pre-transmission to 73% post-transmission.
The Centers for Disease Control and Prevention requires antibody testing by all OPOs. However, only about 50% OPOs perform NAT for HIV and hepatitis C.
The window period between acquisition of infection and serologic detectability is much shorter when NAT is used, so NAT might mitigate the infectious risk and increase comfort with HRD use, which may explain the increase in HRD transplants in OPOs that perform the test.
NAT is not used universally because it is expensive, time consuming, and has a higher rate of false positives compared with antibody testing, which could lead to discard of viable organs and exacerbate an already severe shortage.
However, NAT may be appropriate for high-risk donors because a NAT test means a lower probability of a false-negative result.
For now, she said, many organs are being discarded that may well be worth using. “The death rate on dialysis is very high. So I think the question is, ‘Is it better to wait on dialysis or accept an organ with a slight increased risk of infectious transmission?'” Kucirka said.