The relationship between the level of urinary biomarker for acute kidney injury and the prognosis of ANCA associated glomerulonephritis

LI Kang; LIU Zheng-zhao; CHEN Ying-hua; YANG Liu; ZHANG Hai-tao; CHEN Hui-ping; HU Wei-xin

doi:10.19538/j.nk2017040116

Abstract：Objective To analyse the relationship between the level of urine NGAL or KIM-1 and the severity or prognosis of ANCA associated glomerulonephritis.Methods 69 patients with ANCA associated glomerulonephritis were included,among which 30 patients are males,39 patients are females,61 patients are anti-MPO-ANCA positive and 8 patients are anti-PR3 positive.All patients received renal biopsy.The kidney tissues were analysed including the renal histological classification,semi-quantitative score of tubulointerstitial.Urine NGAL and KIM-1 is tested with ELISA.The relationship between urine NGAL or KIM-1 and the data including serum creatinine,urinary protein and serum albumin is analyzed by Spearman r test.Parameters between groups were compared using the Mann-Whitney.Results Among the 69 patients,14 patients are focal type,26 patients are crescentic type and 29 patients are mixed type.Baseline data:serum creatinine is 3.13(0.54～13.5)mg/dL,urinary protein is 1.61(0.11～9.78)g/24h.There are no significant differences for urine NGAL and KIM-1 between different histological types.Urine NGAL is positively correlated with urinary protein and serum creatinine (r=0.3242,0.3257;P=0.0095,0.0081).Urine NGAL is negatively correlated with serum albumin(r=-0.3964,P=0.0009).Urine KIM-1 is negatively correlated with serum albumin(r=-0.2539,P=0.0413),but not with serum creatinine and urinary protein.Urine KIM-1 in the high scores group for the interstitial inflammation index is significantly higher than the low scores group(P=0.0413).Urine NGAL is not significantly correlated with scores for the interstitial inflammation index.Among 45 patients who were followed up for 24(14-58)m,the urine NGAL of the patients who had renal progression is significantly than the urine NGAL of the patients who had no renal progression [117.6(3.06～518.4) μ g/L vs 28.86(2.17～461.5) μ g/L,P=0.0372],In a multivariate Cox regression model,Urine NGAL (HR 1.012,95％CI 1.001-1.022,P=0.033) was independent predictors associated with adverse renal outcome.Conclusion Urine NGAL can reflect the severity of ANCA associated glomerulonephritis and it was independent predictors associated with adverse renal outcome.Urine KIM-1 is higher in the group who had high scores for the interstitial inflammation index.