Objective  To explore the activity of ANCA positive disease in children with lupus nephritis （LN） and examine its impact on the severity of disease to provide evidence-based rationales for rapid diagnosis, reasonable clinical decision-making and standardized management and offer new ideas for managing systemic lupus erythematosus （SLE）.

Methods  From January 2014 to April 2022, retrospective review was conducted for the relevant clinical data of 170 hospitalized LN children. Experimental group had 93 children with ANCA testing and 33 were positive for ANCA. Clinical manifestations, laboratory tests, SLE Disease Activity Index （SLEDAI） score, treatments and prognoses of this group were compared with other 60 ANCA-negative children （control group）. SPSS22.0 software was utilized for performing statistical analysis.

Results  The most common manifestations in LN children were proteinuria （59.13%）, fever （48.38%）, edema （39.78%） and hematuria （34.4%）. The degree of renal damage was significantly greater in ANCA-positive group than that in ANCA-negative group. And 24-hour urinary protein quantity of ANCA positive group was higher than that of ANCA negative group. No significant differences existed between ANCA-positive and ANCA-negative SLE children in blood routine, liver/kidney function, lipids, immunoglobulins, complement or inflammatory parameters. SLEDAI scores were significantly higher in ANCA-positive group than those in ANCA-negative group （mean SLEDAI scores were 15.62 and 11.78, P = 0.033）. The survival rate of ANCA positive group was lower than that of ANCA negative group.

Conclusions  ANCA-positive LN children have greater disease activity, worse basic renal function and a higher probability of poor clinical prognosis.