Abstract: Background： Crescents are a common pathological feature in patients with purpura nephritis (HSPN), but there are few reports on the correlation between the proportion of crescents and the clinical and pathological features of children with HSPN. Objective：To compare the clinical and pathological features of HSPN children with different crescentic ratios. Design：Case series report. Methods：The hospitalized children were enrolled between January 2013 to December 2017 at the Pediatric Nephrology Center of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine where they were diagnosed with HSPN and underwent the first renal biopsy with a crescent ratio ≤ 50%. According to the crescent proportion in the pathological report of renal biopsy, patients were divided into no crescent group, crescent <25% group and crescent 25% to 50% group. The general information, clinical manifestations, laboratory test indicators before renal biopsy, and pathological report of the renal biopsy were intercepted from the medical records, and compared between groups. Main outcome measures：The relationship between crescent ratio and clinical manifestations and renal pathological features. Results：A total of 416 children with HSPN were included in the analysis, including 167 cases in the no crescent group, 222 cases in the crescent <25% group, and 27 cases in the crescent 25% to 50% group. For clinical manifestations, the incidence of edema in the crescent <25% group and the crescent 25% to 50% group was higher than that in the no crescent group. Hematuria plus proteinuria was the main clinical type in the three groups. The proportion of nephrotic syndrome in the crescent 25% to 50% group was higher than that in the other two groups, and the differences were statistically significant. For laboratory examination indicators, the 24h urine protein quantification and BUN level in the crescent 25% to 50% group were higher than those in the other two groups, and the eGFR was lower than that in the other two groups. The levels of CRP and Ddimer in the crescent <25% group and the crescent 25% to 50% group were higher than those in the no crescent group. Scr in the crescent 25% to 50% group was higher than that in the no crescent group. The differences were statistically significant. According to the glomerular pathology, the proportions of fibrinoid necrosis and endothelial cell hyperplasia in the crescent <25% and 25% to 50% groups were higher than those in the no crescent group. The proportion of interstitial pathology graded as + and the proportion of C3 and fibrinogen (FIB) graded as ++ gradually increased with the growing crescent ratio. The differences were statistically significant. There is a positive correlation between the crescent proportion and the degree of renal tubular interstitial pathological grade (r=0.308, P<0.001), and a weak positive correlation with the degree of C3 deposition (r=0.139, P=0.005) and the degree of FIB deposition (r=0.177, P<0.001). Conclusions：There is a parallel relationship between the crescent proportion and the severity of glomerular pathology, tubular interstitial injury, C3 and FIB deposition, and clinical staging in HSPN children.

Key words: Crescentic bodies, Purpura nephritis, Clinical manifestation, Renal pathology