Pediatric Donor Glomerulopathy Incidence, Risk Factors, and Complications

Background: Studies on the outcome of recipients of deceased pediatric donor kidneys (PDKs) compared to recipients of adult donor kidneys (ADKs) are inconclusive. Some studies demonstrate comparable long-term graft survival but with some recipients developing pediatric donor glomerulopathy (PDG), characterized by irregular lamellation and splitting of the outer aspect of the glomerular basement membrane (GBM). This study aims to assess the incidence, association with abnormal urinalysis, and potential risk factors of PDG. Methods: Retrospective review of the records of kidney recipients of PDKs ≤ 15 years of age who were transplanted at Mayo clinic in Minnesota between 1994 and 2024. Thirty-six recipients gave authorization for research and were included. Clinical and pathological information was obtained from existing databases. Biopsies were examined by light microscopy, immunofluorescence and electron microscopy. Results: Ten recipients (27.8 %) from our cohort showed evidence of PDG (diffuse or segmental GBM involvement). PDG developed at a median of 42 months range [1-4 Years) post-transplantation. PDG group donors were younger (median 9 [5,14] vs. 12[6,15]), and smaller (median 32 Kg [22.2,54] vs 44.2 Kg [22.2,114.8]) in the non PDG group). Proteinuria defined as >500 mg /24 hours was more common in the PDG group (3 patients vs 1). Hematuria was also more common in PDG group 4 vs 1 patient but 3 of 4 patients had IgA deposition. Conclusion: Pediatric donor glomerulopathy developed in about quarter of recipients of PDKs in our cohort, between 12 months and 4 years post-transplantation, and there was a trend toward association with donor’s younger age and lower weight. Proteinuria was numerically more common in the PDG group.