Pathological And Clinical Analysis Of Tubulointerstitial Injury In Children With Minimal Change Nephrotic Syndrome

Objective: To probe pathological and clinical characteristics of minimal change primary nephrotic syndrome(PNS)with tubulointerstitial lesions(TIL)in children.Methods: The clinical and pathological data of 148 children with PNS who were hospitalized in the Department of Nephrology,Children's Hospital of Chongqing Medical University from January 2013 to November 2017 were retrospectively analyzed.According to whether tubulointerstitial injury occurred,the children were divided into TIL group and Non-TIL group,and the clinical manifestations and laboratory data were compared between the two groups.The follow-up data of 124 children with minimal change nephrosis(MCN)were analyzed to explore the effect of TIL on the outcome of children with MCN.Results:(1)Among the 148 cases,children with MCN accounted for 79.1% of children with PNS who underwent renal biopsy at the same time,aged 1.50-17.50 years,with an average age of 8.88 years.(2)28 cases of tubulointerstitial lesions,accounting for 18.9%,including 25 males and 3 females,and the ratio of male to female is 8.3:1,aged 3.08-17.50 years,with an average age of 9.52 years.(3)Renal tubular dilation and interstitial inflammatory cell infiltration are common pathological types of TIL.(4)TIL occurred in 13 patients with simple nephropathy,15 patients with nephritic nephropathy,and increased in children with nephritic nephropathy,but there was no significant difference(P > 0.05);Hematuria is a common clinical manifestation of tubulointerstitial injury in nephritic nephropathy.(5)Serum albumin level in TIL group was lower than that in non-TIL group,while urea nitrogen,serum creatinine,serum uric acid,cystatin C,beta-2 microglobulin and 24-hour urine protein levels in TIL group were higher than those in control group.There was significant difference between the two groups(P > 0.05).(6)124 children with MCN were followed up from 0.16 to 5.92 years,90 cases had complete remission,15 cases had partial remission and 19 cases had no remission;15 cases had complete remission,7 cases had partial remission and 2 cases had no remission in TIL group,75 cases had complete remission,8 cases had partial remission and 17 cases had no remission in non-TIL group;the complete remission rate in non-TIL group was higher than that in TIL group,but the difference was not statistically significant(P=0.426).Conclusion:(1)In our center,62.2% of children with minimal change nephrotic syndrome were simple type,37.8% were nephritis type,and hematuria was the main clinical manifestation of children with MCN complicated with TIL.(2)Renal tubular dilation and interstitial inflammatory cell infiltration are common pathological types of TIL.(3)When children with nephrotic syndrome have hematuria,renal insufficiency,increased uric acid and increased excretion of beta 2-MG,we should be alert to the occurrence of tubulointerstitial injury on the basis of glomerular lesions.Renal biopsy should be performed as soon as possible to clarify the pathological changes.(4)In this group of data,the occurrence of TIL had no effect on the outcome of MCN.