307.4 Incidence and risk factors for de novo donor-specific antibody development post pediatric kidney transplant: Retrospective analysis of longitudinal Cohort
Monday May 06, 2019 from 10:00 to 11:00
Bayshore F
Presenter

Alanoud Alshami, Saudi Arabia

Consultant Pediatric Nephrologist

Pediatric Nephrology and Kidney Transplant

King Fahad Specialist Hospital Dammam (kfsh-d)

Abstract

Incidence and risk factors for de novo donor-specific antibody development post pediatric kidney transplant: Retrospective analysis of longitudinal Cohort

Alanoud A. Alshami1, Ahmed A. Azzam1, Rabab A. Al Attas1,2, Ammar Hamed1, Mohammed F. Kasem1, Mohammed A. Almaghrabi1, Abdulaziz K. Hassan1, Fatimah H. Khalifa1.

1Pediatric Nephrology and Kidney Transplant/ Multi Organ Transplant Center, King Fahad Specialist Hospital- Dammam, Dammam, Saudi Arabia; 2Histocompatibility and immunogenetics/ Pathology and Laboratory Medicine, King Fahad Specialist Hospital- Dammam, Dammam, Saudi Arabia

Introduction: Post kidney transplant de novo DSA (dnDSA) has been linked to rejection and inferior graft outcome. However, the incidence and risk factors of post-transplant dnDSA has not been well studied in pediatric. T

Methodology: In mid 2015, we implemented standardized protocol DSA monitoring at 6 months and 1 year post transplant and then annually thereafter. We have also started doing protocol biopsy at 6 months and 1 year and as clinically indicated. All positive dnDSA with MFI> 2000 has been treated regardless of the biopsy results. This is a retrospective study for data that was collected longitudinally. 46 low risk children < 16 years of age who underwent single kidney transplant from June/2015- April/2018 were enrolled. 

Results: Out of 46, 24(52.17%) patients developed dnDSA at median time of 1.36year s (IQ 0.8-3.2). DQ dnDSA accounted for 84% of post-transplant DSA. Median follow up time for all patients was 2.4 years (QI 0.6-3.4) After adjusting for all possible predictors, Cox proptional regression hazards showed that mean Tac level in the 3 clinic visits preceding dnDSA development was the only independent risk factor for dnDSA development (aHR 1.083 CI 1.012-1.16, P= 0.022). However, mean eGFR at las follow up was similar between those who develop dsDSA and those who did not (79.36 ml/min/1.73m2 vs 89.16 ml/min/1.73m2) p=0324. Total of 99 kidney biopsies were performed. Out of them 61 (61.6%) protocol biopsy and 38 (38.3%) indicated biopsy (performed if creatinine is high). The incidence of microvascular inflammation 27.87% and subclinical AMR 6.6% were higher in the protocol biopsy group compared to 13.2% and 2.63% respectively in the indicated biopsy group (p=0.058). On the other hand, ACR incidence (26.31%) was higher in the indicated biopsy group compared to the protocol biopsy group 1.6% (p=0.034)

Conclusion: The incidence of post kidney transplant dnDSA was high in our cohort. Furthermore, the incidence of microvascular inflammation in protocol biopsies was also high indicating an early antibody mediated injury. dnDSA screening and protocol biopsy have led to early intervention and good short-term graft outcome. However, we need larger studies with longer follow up time to draw solid conclusion.


© 2021 IPTA 2019