Abstract:

Objective: We explored the relevance of the markers with tubular interstitial lesion and glomerular function in patients with focal segmental glomerulosclerosis (FSGS) in order to find the specific and sensitive biomarkers. Methodology: Sixty patients with biopsy-proved idiopathic FSGS were recruited in this study. 36 idiopathic menbranuous nephropathy (MN) and 30 minimal change diseases (MCD) were regarded as the control groups. The changes of urinary kideny injury molecule-1 (KIM-1), IL-18, neutrophil-gelatinase-associated lipocalin (NGAL), proteinuria, N-acetyl-β-glucosaminidase (NAGase), retinal-binding protein (RBP), Cystatin C (CysC), C3, α2-MG and renal biochemistry were observed in each group and compared. The effects of urinary data, blood biochemistry as well as histological manifestations on the changes of KIM-1, IL-18, NGAL in FSGS patients were evaluated. Results: ⑴Under the same proteinuria level, urinary KIM-1, IL-18, NGAL, NAG, RBP, C3, α2-MG were increased in patients with FSGS compared with MN and MCD (P<0.05). ⑵ In FSGS patients, urinary KIM-1 was increased along with serum CysC (P<0.05), and the patients with higher urinary NGAL showed proteinuria, BUN, urinary C3 and α2-MG increased (P<0.05), but serum total protein and albumin decreased (P<0.05). ⑶ FSGS patients with acute tubular interstitial injury showed KIM-1 and NGAL increased compared with that have only chronic tubular interstitial lesions (P<0.05). ⑷ In 21 patients with normal NAG and RBP, their urinary KIM-1, IL-18, NGAL was also increased, and the acute tubular interstitial lesions were found in histological examinations. Regard to diagnosis acute tubular and interstitial injury, the area under ROC curve of KIM-1, NGAL and NAG were greater than that of IL-18, RBP and CysC. Conclusion: Our study demonstrated the patients with FSGS had serious tubular interstitial damages compared with MN and MCD, and the reason was independent of the quantity of proteinuria. KIM-1, NGAL, NAG are more specific and sensitive novel biomakers than IL-18, RBP and CysC to estimate the acute tubular and interstitial function.