S CHAN1,2,3, E PASCOE1,2,3, P CLAYTON1,4,5, S MCDONALD1,4,5, W LIM1,6, M SYPEK1,4,5, S PALMER7, R FRANCIS2,3, S CAMPBELL1,2,3, C HAWLEY1,2,3, D JOHNSON1,2,3
1Australian and New Zealand Dialysis and Transplant Registry, Adelaide, Australia, 2Department of Nephrology, Princess Alexandra Hospital, Brisbane, Australia, 3Australasian Kidney Trials Network, Faculty of Medicine, The University of Queensland, Brisbane, Australia, 4Central Northern Adelaide Renal and Transplantation Service, Royal Adelaide Hospital, Adelaide, Australia, 5School of Medicine, University of Adelaide, Adelaide, Australia, 6Sir Charles Gairdner Hospital Unit, The University of Western Australia, Perth, Australia, 7Department of Medicine, University of Otago, Christchurch, New Zealand
Aim: To examine the aetiology and predictors of infection-related mortality among kidney transplant recipients in Australia and New Zealand.
Background: Infections following kidney transplantation are associated with significant morbidity and mortality. However, there has been limited study regarding the burden and risk factors for infection-related mortality in kidney transplant recipients.
Methods: This study included all Australian and New Zealand kidney transplant recipients who had a first graft between January 1, 1997 and December 31, 2015, using Australia and New Zealand Dialysis and Transplant Registry data. Infection-related mortality was evaluated by multivariable competing risk regression with non-infectious mortality as the competing risk.
Results: A total of 12,519 kidney transplant recipients were included (median age (IQR) 46 (36-55)yrs, males 63%, diabetes 15%, Indigenous 6%). Of the 2,197 deaths, 416 (19%) were infectious and of these, 224 (54%) were bacterial. Higher infectious mortality was associated with older age (20-30yrs reference; ≥60yrs subdistribution hazard ratio (SHR) 3.98, 95% CI 1.98-8.02), female gender (SHR 1.56, 95% CI 1.17-2.15), indigenous ethnicity (SHR 3.33, 95% CI 2.09-5.29, compared with Caucasian ethnicity), earlier transplant era (1997-2005 reference; 2006-2015 SHR 0.56, 95% CI 0.31-0.84), and use of thymoglobulin/ OKT3 for both induction therapy and treatment of rejection (daclizumab/ basiliximab reference; SHR 2.18, 95% CI 1.47-3.23). Polycystic kidney disease was associated with a lower hazard of infectious mortality (glomerulonephritis reference; SHR 0.52, 95% CI 0.28-0.99). There was no association between infectious mortality and donor characteristics.
Conclusions: Older age, female gender, indigenous ethnicity, earlier transplant era and use of T-cell depleting therapy are associated with increased infectious mortality following kidney transplantation. Bacterial infections are the commonest cause of infectious death in transplant recipients.
Dr Samuel Chan is a final year nephrology advanced trainee working for Queensland Health. He has also commenced his PhD with the Department of Nephrology and the Australasian Kidney Trials Network at the Princess Alexandra Hospital in Brisbane, Queensland. Dr Chan’s studies will be centred around infectious complications following kidney transplantation.