Dr Rachael Kermond1, Dr Siah Kim2,3, Prof Fiona Mackie1,5, Dr Anne Durkan2,3
1Sydney Childrens Hospital Randwick, Randwick, Australia, 2Childrens Hospital Westmead, Westmead, Australia, 3Centre for Kidney Research, the CHildren’s Hospital at Westmead, Westmead, Australia, 4School of Paediatrics and Child Health, UNiversity of Sydney, Sydney, Australia, 5School of paediatrics, UNSW, Sydney, Australia
Background:
Human leukocyte antigen (HLA) donor specific antibodies (DSA) are implicated in antibody-mediated rejection (AMR), graft dysfunction and failure in kidney transplant (KT) recipients. Evidence suggests that non-HLA antibodies including AT1R also play a role in AMR, impact graft function and survival. Data is variable and limited in paediatric KT cohorts.
Aim:
To assess the effect of AT1R antibodies on rejection, graft function and survival in paediatric KT recipients.
Methods:
A retrospective cohort study was conducted across two paediatric KT centers. Paediatric recipients from 2007-2021 with at least one AT1R antibody level post-transplant were included. Demographic data, development of de-novo DSA, graft function, graft failure, episodes of biopsy proven rejection, proteinuria and hypertension were collated.
Results:
Of 69 eligible individuals, 81% recorded a positive AT1R antibody level (≥10 U/ml). Demographic data including age at transplant, source of KT, cause of end stage kidney disease, induction and maintenance immunosuppression, HLA matching, eplet load, de-novo DSA development, EBV and CMV status did not differ between groups. AT1R antibody positivity was not statistically associated with the development of hypertension (p-value 0.9), proteinuria (p-value 0.6), graft failure (p-value 0.6) or eGFR at one, two or five years (p-value 0.2, 0.5, 0.3 respectively). There was also no correlation between AT1R antibody and risk of rejection (AMR, T-cell mediated or mixed), even when accounting for confounding factors with multivariate analyses.
Conclusion:
Our paediatric KT recipient population demonstrated a high prevalence of AT1R Ab positivity (81%). This did not correlate with any statistically significant risk of hypertension, proteinuria, graft dysfunction, failure, or episodes of rejection.
Biography:
Dr Rachael Kermond is an Advanced Paediatric Nephrology Trainee who has completed fellowships in Adelaide, Melbourne and Sydney. During her training she has been involved in multiple research projects including the recent commencement of a Masters by Research.