Prevalence and Consequences of Glomerular Hyperfiltration (HF) in Pediatric Solid-Organ Transplant (SOT) Recipients

Background: The prevalence and sequalae of glomerular HF are unknown in pediatric SOT. We aimied to describe HF in a pediatric SOT cohort. Methods: We reviewed all actively followed SOT at a large quatenary pediatric referral center from 2002-2023. Patients were excluded if they had muscular dystrophy or were under the age of 2. The primary outcome was estimated renal function (creatinine based CKiD U25) yearly during the first 5 years post-transplant and the most recent visit. HF was defined as 2 standard deviations above the mean eGFR for age at anytime. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) of less than 90mL/min/1.73m2. Secondary outcomes included any rejections and hypertension (HTN). We used a contigency table to determine odds ratio. Results: A total of 402 patients were eligible. Of the 129 kidney transplant recipients, only one had HF. The clinical characteristics of the remaining patients are shown in Table 1, with 44 (16%) demonstrating HF at some point during the first 5-years post-transplant. Table 2 depicts the clinical associations based on renal function in liver and heart transplant recipients. Patients in both the HF and CKD groups had a 2.22 higher odds of having HTN compared to those with normal function (p=0.024 and 0.008,respectively). The non-renal transplant CKD group also had a 1.8 higher odds of having any episodes rejection (p=0.02). Conclusion: While HF is uncommon in pediatric kidney transplant recipients, it is prevalent in pediatric liver and heart transplant recipients. HF and CKD are both independently associated with an increased risk for HTN in these non-renal transplant patients. Close follow-up for progression and sequalae of CKD is thus warranted in this high risk SOTr population.