S CHAN 1,2,3, M MORRISON 4, C HAWLEY 1,2,3, S CAMPBELL 1,2,3, R FRANCIS 1,2,3, N ISBEL 1,2,3, E PASCOE 2, D JOHNSON 1,2,3
1Department of Nephrology, Princess Alexandra Hospital, Woolloongabba, Australia, 2Australasian Kidney Trials Network, The University of Queensland, Brisbane, Australia, 3Translational Research Institute, Brisbane, Australia, 4The University of Queensland Diamantina Institute, Faculty of Medicine, University of Queensland, Woolloongabba, Australia
Background: Gut microbial dysbiosis has been frequently implicated in systemic diseases. Few studies have examined dysbiosis following kidney transplantation. The aim of this study was to ascertain whether changes occur in the gastrointestinal microbiota of the kidney donor and recipient following kidney transplantation.
Methods: Kidney transplant recipients and their donors were prospectively enrolled in a pilot study to collect one faecal sample prior to, and another faecal sample between four to eight weeks following surgery. Gastrointestinal microbiota richness, Shannon diversity measures and functional assessments of both kidney donors and recipients were analysed via metagenomic sequencing.
Results: The study included 12 donors (median age 56 years, 6 females) and 12 recipients (median age 51 years, 3 females). The microbiota of donors showed no significant changes in gastrointestinal microbiota richness, Shannon diversity, or functional assessments before and after nephrectomy. In contrast, the microbiota of kidney transplant recipients was altered post-transplant, reflected in reductions of the mean (±SD) richness values (156 ± 46.5 to 116 ± 38.6, p=0.002), and Shannon diversity (3.57 ± 0.49 to 3.14 ± 0.52, p=0.007), and a dramatic increase in Roseburia spp. abundance post-transplant (26-fold increase from 0.16 ± 0.0091 to 4.6 ± 0.3; p=0.006; FDR=0.12). Functionally, the post-transplant microbial community shifted towards those taxa using the glycolysis pathway (1.2-fold increase; p=0.02; FDR=0.26) for energy metabolism.
Conclusion:Live donor kidney transplantation and standard care post-transplant result in significant alterations in gut microbiota richness, diversity, composition and functional parameters in kidney transplant recipients but not in their kidney donors.
Dr Samuel Chan is a PhD student working at the Princess Alexandra Hospital, Brisbane, Queensland. He is a staff specialist, nephrology undertaking his PhD in the area of transplant infectious diseases. His PhD is supported by the NHMRC Postgraduate Scholarship and he was awarded the NHMRC Sir Gustav Gossal prize in 2019 for being the highest ranked NHMRC postgraduate scholarship recipient in Australia.