Abstract:Objective To study the clinicopathological features of children with lupus nephritis (LN) with positive anti-neutrophil cytoplasmic antibody (ANCA). Methods A retrospective analysis was performed for the children who were diagnosed with LN in the First Affiliated Hospital of Sun Yat-sen University from January 2003 to December 2019. According to the results of serum ANCA, they were divided into two groups: ANCA-positive group (n=59) and ANCAnegative group (n=454). The two groups were compared in terms of clinical manifestations, histopathological features, remission rate, and prognosis. Results Compared with the ANCA-negative group, the ANCA-positive group had a significant reduction in leukocytes and a significant increase in erythrocyte sedimentation rate (P < 0.05). There were no significant differences between the two groups in serum creatinine, urine protein, and urine red blood cell count (P > 0.05). A total of 308 children underwent kidney biopsy. The results on light microscopy showed that compared with the ANCAnegative group, the ANCA-positive group had a significantly higher proportion of children with cellular fibrous crescents (P < 0.05) and a significantly lower proportion of children with immune complex deposition (P < 0.05). There were no significant differences between the two groups in the remission rate and survival rate (P > 0.05). Conclusions Children with ANCA-positive LN tend to have more severe renal pathological injury, which is not exactly parallel with clinical manifestations, suggesting that timely renal biopsy is of great importance.