Analysis of related factors of acute kidney injury in adult minimal change nephrotic syndrome

Abstract

Objective To investigate the related factors of acute kidney injury (AKI) in adult minimal change disease (MCD). Methods A retrospective analysis was made in the patients (>18 years old) with first-presented nephrotic syndrome and biopsy-proven MCD from January 1, 2002 to December 31, 2015. The patients were divided into two groups: the AKI group and the non-AKI group. Univariate and multivariate logistic regression were used to analyze the influencing factors associated with the occurrence of AKI. And the interaction of AKI related factors was tested. Results A total of 403 patients were included. The ratio between males and females was 1∶1.13. The average age at renal biopsy was 39.5 ± 15.1 years. AKI occurred in 118 cases (29.3%) of the 403 patients. The AKI group had statistically significant differences in age, gender, urinary protein quantification, serum albumin, serum creatinine, blood urea nitrogen, estimated glomerular filtration rate (eGFR), tubular atrophy, and renal interstitial lesions compared with the non-AKI group (P<0.05). Univariate logistic regression analysis showed that the elderly age, maleness, higher urinary protein, tubular atrophy, renal interstitial edema, interstitial fibrosis, inflammatory cell infiltration, and hypertension were the risk factors for the occurrence of AKI in adult MCD. Interaction tests showed that the effect of serum albumin on AKI was significantly affected by renal interstitial fibrosis (P=0.005), and this interaction was still significant after adjustment of such factors as age group, gender, hypertension, urinary protein quantification, tubular atrophy, renal interstitial edema, and renal interstitial cell infiltration (P=0.0 263). In the non-interstitial fibrosis patients, serum albumin increase was an independent protective factor for AKI (adjusted OR, 0.8; 95%CI, 0.7-0.9, P<0.001). In the interstitial fibrosis patients, the influence of serum albumin increase on AKI was not significant (adjusted OR 1.0, 95%CI, 0.9- 1.0, P=0.0 278). Conclusion Elderly age, maleness, higher proteinuria, renal tubular atrophy, renal interstitial edema, renal interstitial fibrosis, inflammatory cell infiltration, and hypertension, were risk factors for the occurrence of AKI in adult MCD. The protective effect of serum albumin increase on AKI was influenced by the renal interstitial fibrosis. Key words: Acute kidney injury; Adult; Minimal change disease; Nephrotic syndrome; Serum albumin