The children with AAGN admitted to all cooperating units during 2017.01.01 to 2022.12.31 were followed up for more than 6 months, and the case data were complete.

PARRG Classification (pediatric AAGN renal risk grade, pediatric AAV renal risk grade, PARRG) According to the PARRG grading method provided by the Affiliated Children's Hospital of Chongqing Medical University, the enrolled children with AAGN were classified into high risk group, medium risk group, low risk group, medium risk group, low risk combination and low risk group according to the two indexes of eGFR and percentage of glomerular sclerosis during renal biopsy.

PARRG risk grading criteria:

There are two risk factors for ESRD: (1) eGFR≤20ml/min/1.73m2 at renal biopsy; ② The proportion of glomerular sclerosis ≥30%; High risk resistance: meet 2 risk factors; Moderate risk group: only 1 risk factor; Low risk group: no above risk factors;

The children with AAGN admitted to all cooperating units during 2017.01.01 to 2022.12.31 were followed up for more than 6 months, and the case data were complete.

PARRG Classification (pediatric AAGN renal risk grade, pediatric AAV renal risk grade, PARRG) According to the PARRG grading method provided by the Affiliated Children's Hospital of Chongqing Medical University, the enrolled children with AAGN were classified into high risk group, medium risk group, low risk group, medium risk group, low risk combination and low risk group according to the two indexes of eGFR and percentage of glomerular sclerosis during renal biopsy.

PARRG risk grading criteria:

There are two risk factors for ESRD: (1) eGFR≤20ml/min/1.73m2 at renal biopsy; ② The proportion of glomerular sclerosis ≥30%; High risk resistance: meet 2 risk factors; Moderate risk group: only 1 risk factor; Low risk group: no above risk factors;

The high-risk group: methylprednisolone intravenous 15-30mg/kg/d (Max.500mg/d)*3 days , with 2 courses, interval 5-7 days;Oral prednisone acetate 1.5-2mg/kg/d (Max. 60mg/d) during methylprednisolone impact interval and later stage, with the first reduction after 2-4 weeks. The dose was reduced once every 3 weeks in the first 3 months, and once every 4 weeks in the next 3 months, with a reduction of 5-10mg/ day each time; Rituximab：375 mg/m2/ time, once a week for 4 times;Intravenous cyclophosphamide 7.5-10mg/kg.d*2 days(Max.500mg/d), once every 4 weeks, twice in total, at the 8th and 12th week.The medium-low risk group: methylprednisolone was the same dose as before, but only with 1 course, then followed by oral prednisone acetate 1.5-2mg/kg/d (Max. 60mg/d), divided into three times for 3 weeks, and then changed to morning daily; The dose was reduced as the high-risk group ;Rituximab was the same dose as before.

The rate of complete or partial response to ANCA vasculitis-associated nephritis (AAGN) was assessed at 6 months. Complete AAGN response was defined as: 1. Estimated glomerular filtration rate (eGFR) ≥60ml/min/1.73m2, or a decrease of less than 15% from baseline eGFR; 2. Proteinuria ≤0.3g/24 hours.Partial AAGN response was defined as: 1. Estimated glomerular filtration rate (eGFR) ≥30ml/min/1.73m2, or a reduction of less than 50% from baseline eGFR; 2. Decreased proteinuria>Baseline 50% or 24-hour urinary protein quantification<50mg/Kg.d.

The time to achieve complete and partial AAGN remission