Prognostic Impact of Proteinuria at Manifestation in Adult Nephrotic Syndrome Patients: Insights from a Prospective Cohort Study.

Abstract

Background and objective Nephrotic syndrome is a significant worldwide health concern impacting millions of people and is marked by heavy proteinuria, edema, and decreased serum levels of albumin. Albuminuria arises from abnormal glomerular permeability and impaired tubular reabsorption, contributing to declining kidney function and a heightened risk of cardiovascular complications. The objective of this study was to investigate the prognostic role of proteinuria on the persistent decline in estimated glomerular filtration rate (eGFR) (<30 ml/minute/1.73m2) during follow-up and the dynamics of remission and relapse in various subtypes of nephrotic syndrome. Methods A total of 134 adult patients, diagnosed with various histopathological categories of nephrotic syndrome, were prospectively studied. Urine protein levels were assessed using the pyrogallol red-molybdate (PRM) method. The Kaplan-Meier analysis and log-rank test were utilized to assess the prognostic role of proteinuria at manifestation on persistent decline in estimated glomerular filtration rate(eGFR) (<30 ml/minute/1.73m2) and to evaluate remission and relapse based on proteinuria levels over an 18-month follow-up period. Results Patients with sub-nephrotic levels of proteinuria at manifestation did not progress to end-stage renal disease on follow-up. Patients with sub-nephrotic levels of albuminuria at manifestation were significantly associated with remission on follow-up. The Kaplan-Meier analysis indicated a significant probability of persistent eGFR decline (p < 0.001) in adult nephrotics with higher levels of albuminuria. Furthermore, patients with sub-nephrotic range proteinuria had earlier remission (p < 0.001) compared to those with relapse (p = 0.001) during the follow-up, as demonstrated by log-rank tests. Conclusion This study highlights that sub-nephrotic albuminuria at manifestation is linked to a reduced risk of renal progression and persistent eGFR decline compared to adult nephrotics with higher levels of albuminuria. Early detection and effective management of proteinuria, are crucial for preventing renal function decline and improving patient outcomes.