Kidney Week

Abstract: TH-PO795

Urinary Nephrin and Podocin Levels as Potential Predictors of Reduced Glomerular Filtration Rate after Kidney Transplantation

Session Information

• Transplantation: Clinical - 2
  October 24, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2102 Transplantation: Clinical

Authors

• Souza, Karla, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

Karla Souza, PharmD

• Galdino, Ony Araujo, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

Ony Araujo Galdino, MSc

• De Lima, Mabelle Alves Ferreira, Universidade Potiguar, Natal, Rio Grande do Norte, Brazil

Mabelle Alves Ferreira De Lima, MS

• Pereira, Mauricio Galvao, Universidade Potiguar, Natal, Rio Grande do Norte, Brazil

Mauricio Galvao Pereira, MD, PhD

• Almeida, Jose Bruno, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

Jose Bruno Almeida, MD, PhD

• Ururahy, Marcela, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

Marcela Ururahy, PharmD, PhD

• Rezende, Adriana Augusto de, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

Adriana Augusto de Rezende

Background

Nephrin and podocin could be associated with early podocyte injury, leading to alterations in the glomerular filtration barrier that may result in a reduced glomerular filtration rate (GFR) after kidney transplantation (KTx). Therefore, the aim of this study was to investigate whether the increase in urinary levels of nephrin and podocin is associated with low GFR post-KTx.

Methods

Forty KTx patients aged above 19 years, without a history of segmental and focal glomerulosclerosis or Diabetes mellitus were recruited. Urinary albumin/creatinine ratio (ACR), estimated GFR (eGFR), and serum creatinine were determined. Nephrin and podocin were measured by western blot from urinary extracellular vesicles isolated by ultracentrifugation. All analyses were performed in patients at 3, 6, 9, and 12 months post-KTx.

Results

An increase in ACR and a decrease in eGFR were observed at 12 months compared to 3 months post-KTx. No differences were found in serum creatinine levels. A linear mixed effects model was employed to investigate the association between urinary nephrin and podocin levels with low GFR post-KTx, using eGFR as the dependent variable. The model considered the 12-month follow-up as the fixed effect and included nephrin and podocin as covariates. This analysis indicated an association between urinary nephrin [3 months (p<0.001), 6 months (p=0.031), 9 months (p=0.029), and 12 months (p=0.006)] and podocin [3 months (p<0.001), 6 months (p=0.001), 9 months (p=0.012), and 12 months (p=0.014)] with the reduction of eGFR. To determine if urinary nephrin and podocin could predict low GFR post-KTx, an Area Under the receiver operating Characteristic (AUC) analysis was performed. It was observed that urinary nephrin [3 months (AUC=0.984,p=0.001), 6 months (AUC=0.999,p<0.001), 9 months (AUC=0.929,p=0.001), and 12 months (AUC=0.857,p=0.005)] and podocin [3 months (AUC=0.900,p=0.005), 6 months (AUC=0.999,p<0.001), 9 months (AUC=0.999,p<0.001), and 12 months (AUC=0.913,p=0.001)] were predictors of low eGFR.

Conclusion

The results demonstrate an association between urinary nephrin and podocin and low GFR. Moreover, the high AUC values found during patient follow-up indicate that these urinary proteins are potential predictors of low GFR post-KTx.

Funding

• Government Support – Non-U.S.