Does Size Matter?

Introduction: Acute cellular rejection secondary to de novo Focal segmental glomerulosclorsis after pediatric en bloc renal transplant to a 48 year old female receptient with absence of focal segmental glomerulosclerosis in donor on renal biopsy prior to transplant. Case Description: 48 year old female status post pediatric en bloc renal transplant. She had history of Hypertension,end stage renal disease on hemodialysis. Renal biopsy showed global sclerosis, moderate interstitial fibrosis and thrombotic microangiopathy. Donor : DBD, CPRA 70%, KDPI74%, CIT 12 hours, Terminal Cr 0.25, positive B cell cross match. Induction with thymoglobulin and immunosuppression with Belatacept, tacrolimus , prednsione and mycophenolate motefil. Weaned off tacrolimus 9 months per protocol. 12 months post transplant she had new Class 2 DSA at 5000 MFI and 12 grams proteinuria. Renal biopsy showed moderate tubulitis, extensive effacement and blunting of foot process, C4D negative. Treated with pulse dose steroids,plasma exchange,tacrolimus and prolonged steroid taper. Proteinuria decreased to 3 grams and serum creatinine stable at 0.85. Discussion: Incidence of post transplant proteinuria is higher in adults who received pediatric kidneys compared to those who received adult kidney. Body surface area disparity of > 1.3 m2, recepient weight > 30 kg compared to donor, kidney/ recepient weight ratio <2g/kg is associated with higher risk of graft loss.(Transplantation 2020;104;1695-1702)LMEM