Clinical and renal pathologic analysis of acute interstitial nephritis in 51 children / 中华肾脏病杂志

ABSTRACT

Objective:To discuss the etiology, clinical manifestations and renal pathological features of acute interstitial nephritis (AIN) in children.Methods:The etiology, clinical manifestations, pathological characteristics, clinical effects and outcome of the children with AIN diagnosed by renal biopsy from January 2010 to December 2019 in Nanjing Jinling Hospital were analyzed retrospectively. The Kaplan-Meier method was used to evaluate the kidney survival rate. Cox regression model was built to analyze the risk factors for developing end-stage renal disease (ESRD) at baseline in AIN children.Results:A total of 51 children with AIN were diagnosed by renal biopsy, including 36 males and 15 females. The age was (12.94±2.55) years old (2-17 years old). The clinical manifestations of AIN in children were various and lack of specificity. Only 2 cases (3.92%) had triad. All of the 51 children with AIN showed acute renal injury (AKI), accompanied by increased serum creatinine and decreased estimated glomerular filtration rate. The stage of AKI was mainly stageⅢ(33 cases, 64.71%). Infection was the main cause (38 cases, 74.51%) and drug factor was the second cause (27 cases, 52.94%) in children with AIN. Nonsteroidal antiinflammatory drugs (NSAIDs) were the main inducers of drug-induced AIN (18 cases, 35.29%). The interstitial inflammatory cell infiltration or interstitial edema was found in 51 children. The infiltration of inflammatory cells was mainly mononuclear cells (46 cases, 90.20%). After 4 weeks of treatment, 32 cases (62.75%), 11 cases (21.57%) and 8 cases (15.69%) showed complete, partial and no recovery of renal function, respectively. After 12 weeks of treatment, 49 cases (96.08%), 0 cases (0) and 2 cases (3.92%) showed complete, partial and no recovery of renal function, respectively. After an average follow-up of 4.0(2.0-15.0) months, 2 case (3.92%) patients developed ESRD. The cumulative survival rates of ESRD at 1 year and 2 years after renal biopsy both were 100%, and renal survival rates at 5 years and 10 years were 96.55% and 72.41%, respectively. Multivariate Cox regression analysis results showed that N-acetyl-β-D-glucosidase (NAG) enzyme level>17.6 U/g·cr ( HR=15.729, 95% CI 1.045-15.977, P=0.042) and IgM deposition in renal tissue ( HR=7.523, 95% CI 1.142-9.541, P=0.033) were independent risk factors for developing ESRD in AIN children. Conclusions:AKI is the main clinical manifestation of AIN in children. The characteritic of renal pathology in AIN is tubulointerstitial lesions. After active treatment, most of the patients have a good prognosis. Prevention of infection and rational use of drugs are the key to reduce the incidence rate of AIN in children. The N-acetyl-β-D-glucosidase enzyme level>17.6 U/g·cr and IgM deposition in renal tissue are independent risk factors for developing ESRD in AIN children.