Yuanyuan Zhang1, Aiju Li2, Jiliang Wen3, Junhui Zhen4, Qiufa Hao1, Yidan Zhang1, Zhao Hu1, Xiaoyan Xiao5. 1. Department of Nephrology, Qilu Hospital of Shandong University, Jinan, China. 2. Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, China. 3. Department of Urology, the Second Hospital of Shandong University, Jinan, China. 4. Department of Pathology, Qilu Hospital of Shandong University, Jinan, China. 5. Department of Nephrology, Qilu Hospital of Shandong University, Jinan, China. Electronic address: xiaoyanxiao2007@163.com.
Abstract
BACKGROUND AND AIMS: Kidney injury molecule-1 (KIM-1) was identified the most highly upregulated protein in chronic kidney diseases and prolonged KIM-1 expression may be maladaptive. The present study was aimed to investigate urinary, renal and plasma KIM-1 levels and to analyze association between KIM-1 levels with clinical and pathological indexes in adult Henoch-Schönlein purpura (HSP) patients. METHODS: Twenty healthy individuals, 20 HSP patients without nephritis and 35 HSP patients with nephritis were recruited. Urinary and plasma KIM-1 levels were determined by ELISA and Luminex, respectively. Renal KIM-1 expression was evaluated by immunohistochemistry. RESULTS: HSP patients with nephritis were characterized as elevated levels of urinary, renal and plasma KIM-1. Those with more severe tubular injury of renal biopsy tissues presented significantly higher urinary and renal KIM-1 levels compared to control and patients without nephritis. Urinary and renal levels of KIM-1 were positively correlated with blood urea nitrogen and proteinuria, while they were negatively correlated with eGFR at both baseline and after two years follow-up. Moreover, plasma KIM-1 levels were associated with blood urea nitrogen and proteinuria as well. Further univariate correlation analysis indicated urinary and renal KIM-1 levels were positively correlated with interstitial inflammation index and tubulointerstitial chronicity index. Only urinary KIM-1 levels were associated with interstitial inflammation index, tubulointerstitial chronicity index and extracapillary glomerular activity index, after logistic regression analysis. The area under the curve (AUC) for urinary KIM-1/Cr predicting progression of renal damage was significantly greater than the AUC for proteinuria. CONCLUSIONS: This finding suggests that measurement of urinary and renal KIM-1 level may be helpful to evaluate severity of renal pathological damage and prognosis in adult HSP patients with nephritis.
BACKGROUND AND AIMS: Kidney injury molecule-1 (KIM-1) was identified the most highly upregulated protein in chronic kidney diseases and prolonged KIM-1 expression may be maladaptive. The present study was aimed to investigate urinary, renal and plasma KIM-1 levels and to analyze association between KIM-1 levels with clinical and pathological indexes in adult Henoch-Schönlein purpura (HSP) patients. METHODS: Twenty healthy individuals, 20 HSP patients without nephritis and 35 HSP patients with nephritis were recruited. Urinary and plasma KIM-1 levels were determined by ELISA and Luminex, respectively. Renal KIM-1 expression was evaluated by immunohistochemistry. RESULTS: HSP patients with nephritis were characterized as elevated levels of urinary, renal and plasma KIM-1. Those with more severe tubular injury of renal biopsy tissues presented significantly higher urinary and renal KIM-1 levels compared to control and patients without nephritis. Urinary and renal levels of KIM-1 were positively correlated with blood ureanitrogen and proteinuria, while they were negatively correlated with eGFR at both baseline and after two years follow-up. Moreover, plasma KIM-1 levels were associated with blood ureanitrogen and proteinuria as well. Further univariate correlation analysis indicated urinary and renal KIM-1 levels were positively correlated with interstitial inflammation index and tubulointerstitial chronicity index. Only urinary KIM-1 levels were associated with interstitial inflammation index, tubulointerstitial chronicity index and extracapillary glomerular activity index, after logistic regression analysis. The area under the curve (AUC) for urinary KIM-1/Cr predicting progression of renal damage was significantly greater than the AUC for proteinuria. CONCLUSIONS: This finding suggests that measurement of urinary and renal KIM-1 level may be helpful to evaluate severity of renal pathological damage and prognosis in adult HSP patients with nephritis.