EVALUATION OF SERUM PERIOSTIN AND PIIINP AS BIOMARKERS OF RENAL FIBROSIS AND FUNCTION DECLINE IN RENAL TRANSPLANT PATIENTS

This study aimed to evaluate the potential of serum periostin and N-terminal propeptide of type III procollagen (PIIINP) as biomarkers for predicting renal fibrosis and functional decline in renal transplant patients. We conducted a two-visit observational study among 86 renal allograft patients, reduced to 35 at the two-year follow-up due to the COVID-19 pandemic. Blood samples were collected at baseline and follow-up, while urine samples were collected only at follow-up. Serum levels of PIIINP and periostin were measured using ELISA kits, and various renal function parameters were assessed. Serum PIIINP levels showed a significant decrease over two years (p<0.001, Wilcoxon test), while periostin levels significantly increased (p<0.001, Wilcoxon test). These changes correlated with declines in renal function, as indicated by decreased serum albumin and creatinine clearance levels, and increased serum creatinine levels. Significant correlations were found between changes in PIIINP and creatinine clearance (Spearman coefficient = 0.352, p<0.05), as well as between changes in periostin and creatinine clearance (Spearman coefficient = 0.626, p<0.001). Our findings suggest that serum periostin and PIIINP levels are valuable biomarkers for assessing renal fibrosis and functional decline in renal transplant patients. These biomarkers may provide insights into disease progression and guide therapeutic interventions.