Volume 211 - Issue 9
Extending the criteria for acceptable organ donors: balancing the risks
Authors: Sakhee Kotecha and Trevor J Williams
Med J Aust 2019; 211 (9): 402-403. || doi: 10.5694/mja2.50370
Published online: 4 November 2019
Published online: 4 November 2019
Understanding the low risk of blood-borne virus infections in donors could help expand the pool of available organs
Understanding the low risk of blood‐borne virus infections in donors could help expand the pool of available organs
Solid organ donation and transplantation rates in Australia have increased in recent years, but demand continues to exceed supply.1 Morbidity and mortality for people on the waiting list remain problems, and strategies to expand the donor pool include accepting donations after circulatory death and adopting extended criteria for acceptable donors.2
One group of donors historically excluded from donating comprises people at increased risk of blood‐borne virus (BBV) infections. Evidence from overseas, however, suggests that the actual risks of transmission of the hepatitis B (HBV) and C viruses (HCV) and the human immunodeficiency virus (HIV) via organs from donors at increased risk are low.3,4
In this issue of the MJA, Waller and colleagues5 report their quantification of the risk of BBV infections in Australian organ donors. Estimates of risk in both the overall population and groups at increased risk are provided, including estimates of residual risk for people with negative antibody and nucleic acid test results. The residual risks when nucleic acid test results were negative were found to be very low; even in the groups at highest risk of specific infections, they were only 0.02% (HIV), 0.5% (HBV), and 0.2% (HCV).
Waller and colleagues5 emphasise the need to balance the competing risks for potential recipients of BBV transmission via transplantation against those associated with remaining on the waitlist. Probabilistically, the very low risk of BBV transmission may have less impact on the survival of a potential recipient than a significant delay in receiving an organ. Quality of life while waiting for an organ transplant is poor, and mortality is substantial: 1–5% of patients die while waiting, and another 2–5% become too ill for transplantation and are removed from the waiting list.6,7,8
The evolution of therapeutic options for people with BBV infections has implications for the impact of inadvertently transmitting infections via transplants. HIV infections can now be controlled with highly active antiretroviral therapy, and high quality survival measured in decades is now typical, similar to that of uninfected adults.9 The tolerability of treatment regimens has significantly improved and their pill burden has been reduced. Indeed, HIV infection in a patient is no longer viewed by transplantation programs as an absolute contraindication for receiving an organ transplant.
Outcomes for people with HBV infections have been dramatically improved by interferon and oral nucleotide/nucleoside analogue therapies. Sustained hepatitis B e‐antigen seroconversion (indicating infectiousness) without detectable HBV DNA is found in 15–30% of infected adults and up to 90% of children.10 Virus elimination could potentially be improved by combination therapies, but the reported differences in seroconversion have been small; further, interferon is contraindicated for transplant recipients because of the risk of allograft rejection.11,12 Administering HBV immunoglobulin to liver transplant recipients has successfully prevented re‐infection with HBV, and this approach could be adopted for other solid organ transplants.13 Universal HBV vaccination of potential transplant recipients should substantially mitigate the risk of its transmission.
Patients with HCV infections now have excellent sustained virologic response rates (95–100%) when treated with direct‐acting antiviral agents.14 Similarly high rates have been reported for recipients of organs from people known to be infected with HCV, and early, shorter courses of therapy are well tolerated.15,16,17
The substantially improved outcomes for people with these serious BBV infections require that donor selection be re‐examined, as organ transplants not only improve the patients’ quality of life but are often life‐saving. Receiving a lung transplant has a greater impact upon the life expectancy of a patient with end stage lung disease than the apparent “quality” of the transplanted organ. Appreciation of this fact has led to a gradual shift from rigid adherence to ideal organ criteria to accepting less than perfect organs,18 and this move has not reduced post‐transplantation survival. Given the increase in transplantation numbers and the drop in waiting list mortality, the consequent decline in intention‐to‐treat mortality from the time of waitlisting has resulted in substantially more life‐years being gained in Australia.9
Despite the increasing number of donors, organ transplantation is more difficult in some patients than in others. Smaller women with blood group O, especially if they have had several children, wait much longer for organs and their waitlist mortality is higher, particularly those listed for thoracic organ transplantation, for which size matching is critical.19
With appropriate informed consent, waiting list mortality could be reduced and survival improved for potential organ recipients by judicious acceptance of donors with identified but low risks of BBV infection. For each organ donor offer we need to consider:
- the likelihood of a potential recipient dying while waiting for another organ;
- the probability of transmission of a BBV infection;
- the likelihood of a sustained virologic response or cure with timely therapy, while also taking the risks of such therapy into account; and
- the impact of transplantation on the survival and quality of life of the recipient.
The report by Waller and colleagues in this issue of the Journal provides valuable information regarding the second point, allowing us to discuss with greater precision the risk of transmission of BBV infections, particularly for “difficult to match” recipients.
Competing interests
No relevant disclosures.
References
- Australia and New Zealand Organ Donation Registry. Organ waiting list. https://www.anzdata.org.au/anzod/reports/organ-waiting-list (viewed June 2019).
- Rakhra SS, Opdam HI, Gladkis L, et al. Untapped potential in Australian hospitals for organ donation after circulatory death. Med J Aust 2017; 207: 294–301. https://www.mja.com.au/journal/2017/207/7/untapped-potential-australian-hospitals-organ-donation-after-circulatory-death
- Kucirka LM, Sarathy H, Govindan P, et al. Risk of window period HIV infection in high infectious risk donors: systematic review and meta‐analysis. Am J Transplant 2011; 11: 1176–1187.
- Kucirka LM, Sarathy H, Govindan P, et al. Risk of window period hepatitis‐C infection in high infectious risk donors: systematic review and meta‐analysis. Am J Transplant 2011; 11: 1188–1200.
- Waller KMJ, De La Mata NL, Kelly PJ, et al. Residual risk of infection with blood‐borne viruses in potential organ donors at increased risk of infection: systematic review and meta‐analysis. Med J Aust 2019; 211: 414–420.
- Australia and New Zealand Dialysis and Transplant Registry. Mortality in end stage kidney disease. In: ANZDATA 41st annual report (2018). Adelaide: ANZDATA, 2018. https://www.anzdata.org.au/wp-content/uploads/2018/11/c03_mortality_2017v1.0_20181122.pdf (viewed June 2019).
- Australia and New Zealand Liver Transplant Registry. 29th registry report 2017. Brisbane: ANZLTR, 2017. https://www3.anzltr.org/wp-content/uploads/Reports/29thReport.pdf (viewed June 2019).
- Australia and New Zealand Cardiothoracic Organ Transplant Registry. 2018 report. http://www.anzcotr.org.au/pub/e0cc941a/PDFS/ANZCOTR2018_text.pdf (viewed 24 June 2019).
- Günthard HF, Saag MS, Benson CA, et al. Antiretroviral drugs for treatment and prevention of HIV infection in adults. JAMA 2016; 316: 191–210.
- Defresne F, Sokal E. Chronic hepatitis B in children: therapeutic challenges and perspectives. J Gastroenterol Hepatol 2017; 32: 368–371.
- Liu SK, Seto WK, Lai CL, Yuen MF. Hepatitis B: treatment choice and monitoring for response and resistance. Expert Rev Gastroenterol Hepatol 2016; 10: 697–707.
- Vallet‐Pichard A, Fontaine H, Mallet V, Pol S. Viral hepatitis in solid organ transplantation other than liver. J Hepatol 2011; 55: 474–482.
- Mohanty SR, Cotler SJ. Management of hepatitis B in liver transplant patients. J Clin Gastroenterol 2005; 39: 58–63.
- D'Ambrosio R, Degasperi E, Colombo M, Aghemo A. Direct‐acting antivirals: the endgame for hepatitis C? Curr Opin Virol 2017; 24: 31–37.
- Goldberg DS, Abt PL, Reese PP; THINKER Trial Investigators. Transplanting HCV‐infected kidneys into uninfected recipients. N Engl J Med 2017; 377: 1105.
- Schlendorf KH, Zalawadiya S, Shah AS, et al. Early outcomes using hepatitis C‐positive donors for cardiac transplantation in the era of effective direct‐acting anti‐viral therapies. J Heart Lung Transplant 2018; 37: 763–769.
- Woolley AE, Singh SK, Goldberg HJ, et al; DONATE HCV Trial Team. Heart and lung transplants from HCV‐infected donors to uninfected recipients. N Engl J Med 2019; 380: 1606–1617.
- Snell GI, Westall GP, Oto T. Donor risk prediction: how “extended” is safe? Curr Opin Organ Transplant 2013; 18: 507–512.
- Eberlein M, Reed RM. Donor to recipient sizing in thoracic organ transplantation. World J Transplant 2016; 6: 155–164.
Provenance: Commissioned; externally peer reviewed.