Recommendations Target Prevention of HIV Transmission to Transplant Recipients

In 2009, a kidney transplant recipient in New York City received a kidney that was far from ideal—it carried HIV.

The Centers for Disease Control and Prevention (CDC) recently released the details of a public health investigation into the case, which revealed the first confirmed case of HIV transmission through organ transplantation from a living donor reported since 1989 and the first such transmission documented in the United States since laboratory screening for HIV infection became available in 1985. The CDC’s recent Morbidity and Mortality Weekly Report offers recommendations to help prevent such a serious event from occurring in the future (http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6010a1.htm?s_cid=mm6010a1_w).

“The recent acquisition of HIV through living donor kidney transplantation is extremely unfortunate, both for the specific recipient, and perhaps for public confidence in organ transplant safety more broadly,” said University of Pennsylvania School of Medicine’s Scott Halpern, MD, PhD. “However, this extremely rare event provides both an opportunity for clinicians and transplant programs to revisit their practices and a useful reminder for clinicians and the public alike that no form of organ transplantation can ever be risk-free.” Halpern has published numerous articles on ethical issues related to transplantation.

Public investigation

The public health investigation was initiated after the test results for both the recipient and the donor were positive for HIV approximately one year after the transplant. During the investigation, the donor and recipient, as well as the recipient’s transplant coordinator, nephrologist, and HIV physician, and the donor’s primary care physician and transplant nephrologist, were interviewed. Medical records were also reviewed. The donor reported unprotected sex with one male partner during the year before the transplant, including the time between his initial evaluation and organ recovery.

HIV nucleic acid testing on donor leukocytes collected 57 days before the transplant yielded negative results; however, DNA sequences for three HIV genes (envelope gp41, polymerase, and group-specific antigen p17) were detected from donor leukocytes collected 11 days before the transplant. Recipient serum collected 11 days before the transplant was nonreactive for HIV-1 RNA by Aptima (Gen-Probe), but serum collected 12 days after the transplant was reactive.

HIV DNA sequences from donor and recipient peripheral blood lymphocytes collected on day 404 were analyzed together with HIV DNA obtained from the donor’s frozen leukocyte specimen collected 11 days before the transplant. The gp41, polymerase, and p17 sequences from the donor and recipient were nearly identical, suggesting that the two viruses are highly related.

When to screen

In this particular case, the donor was screened by enzymeimmunoassay 10 weeks before organ procurement but was not rescreened closer to the date of transplant surgery. According to the CDC, because individuals may acquire infections after such an initial evaluation, repeat testing is needed before organs are recovered from living donors.

Transplant centers should screen living donors for HIV as close to the time of organ recovery and transplantation as possible, but no longer than seven days before organ donation, using sensitive tests (such as serology and nucleic acid testing) for both chronic and acute infections. Nucleic acid testing can detect HIV infection before antibodies develop and are detectable by serology.

The window between the time of HIV infection and the time of development of detectable HIV-specific antibodies ranges from three to eight weeks, whereas with nucleic acid testing, the window is estimated to be eight to 10 days. Currently, the combination of HIV nucleic acid testing and serology is used to screen all donors who give blood or tissue; however, nucleic acid testing is not consistently used for screening organ donors.

The CDC recommends that all living donors be informed about modes of transmission and risk factors for HIV infection and counseled to avoid behaviors that would place them at risk for acquiring HIV infection before organ recovery. Individuals with a history of previous high-risk behaviors—such as high-risk sexual activity or use of injection drugs—that are identified during evaluation should receive individualized counseling and should be advised about specific strategies for avoiding risky behaviors. In addition, all transplant candidates should be informed during the evaluation process that despite donor screening, they have a very small risk of acquiring HIV or other infections as a result of transplantation.

“From a public health perspective, the goal is to enact policies that reduce the probability of disease transmission through organ transplantation without further restricting an already scarce organ supply,” Halpern said. “The current CDC recommendations seem likely to toe that line appropriately, but follow-up will be needed to ensure that the new recommendations do not have unintended consequences such as unnecessarily delaying transplantations.”

In 2009, the Living Donor Committee of the Organ Procurement and Transplantation Network (OPTN) and the United Network for Organ Sharing (UNOS) developed a voluntary guidance document for transplant programs regarding the medical evaluation of potential living donors. The document recommends that HIV testing be performed, but it does not identify the type of testing or the timing of the test.

“There is as yet no absolute testing requirement for living donors,” said Connie Davis, MD, who is chair of the committee. “However, UNOS, in cooperation with transplant practitioner societies, is preparing recommendations for the medical evaluation and consent for living donors based upon current scientific knowledge and they should be ready in the next few months. This is part of the OPTN’s new mandate to establish national policy for living donation in addition to that already accomplished for deceased donation.

“Optimizing safety will be a focus of the development of this document. We recognize the unique needs and circumstances involved in living donation and must act to maintain the health and safety of donors and recipients alike.” Davis said.

 

August 2011 (Vol. 3, Number 8)