Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in China

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal involvement.However,there are few studies on the risk factors and predictive models for renal outcomes of AAV in children.Methods Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected retrospectively.The risk factors and predictive model of end-stage renal disease(ESRD)in AAV were explored.Results Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 months.The eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal biopsy.Based on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive model.The Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P<0.001).Compared with serum creatinine at baseline,the predictive model had higher accuracy(0.86 versus 0.58,P<0.001)and a lower coefficient of variation(0.07 versus 0.92)in external validation.Conclusions Renal involvement is the most common manifestation of pediatric AAV in China,of which more than half deteriorates into ESRD.The predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

Efficacy and safety of tacrolimus and low-dose prednisone in Chinese children with steroid-resistant nephrotic syndrome

Background Tacrolimus,a calcineurin inhibitor,is recommended by the recent guidelines from the Kidney Disease Improving Global Outcomes Group as the first-line treatment for steroid-resistant nephrotic syndrome(SRNS),but its clinical application in China is still limited.We investigated the efficacy and safety of tacrolimus combined with low-dose corticosteroids in a population of Chinese children with SRNS.Methods In this prospective non-randomized,non-controlled study,Chinese children with SRNS who failed the previous full-dose prednisone treatment were given tacrolimus(0.1 mg/kg/day)and low-dose prednisone(0.25-0.50 mg/kg/day).We compared the overall remission rate(ORR)and adverse events in the follow-up period with this therapeutic regimen.Results A total of 76 children were enrolled into the study with an average follow-up period of 18±6 months(maximum 36 months).ORR achieved by the first,third,and sixth months was 94.7%,94.7%,and 96.0%,respectively.All patients who attained an initial tacrolimus trough concentration(FK506C0)>6 ng/mL(60.3%)achieved remission.The relative risk of relapse at FK506C0<3 ng/mL compared to 3-6 ng/mL,6-9 ng/mL,and 9-12 ng/mL was 2.3,3.2,and 16.9,respectively.During the follow-up period,adverse effects that had been previously reported were rare.Conclusions Combination of tacrolimus and low-dose prednisone was safe and effective for the treatment of children with SRNS,with high remission rates observed as early as the first month.Relapses were infrequent,but tended to increase significantly with decreases in FK506C0.