OBJECTIVE: With the in-depth study of complement dysregulation, glomerulonephritis with dominant C3 has received increasing attention, with a variety of pathologic types and large differences in symptoms and prognosis between pathologic types. This study analyzes the clinical, pathological, and prognostic characteristics of different pathological types of glomerulonephritis with dominant C3, aiming to avoid misdiagnosis and missed diagnoses.
METHODS: The clinical, pathological, and follow-up data of 52 patients diagnosed as glomerulonephritis with dominant C3 by renal biopsy from June 2013 to October 2022 were retrospectively analyzed. According to the clinical feature and results of pathology, 15 patients with post-infectious glomerulonephritis (PIGN) and 37 patients with of non-infectious glomerulonephritis (N-PIGN) were classified. N-PIGN subgroup analysis was performed, and 16 patients were assigned into a C3-alone-deposition group and 21 in a C3-dominant-deposition group, or 27 in a C3 glomerulopathy (C3G) group and 10 in a non-C3 nephropathy (N-C3G) group.
RESULTS: The PIGN group had lower creatinine values (84.60 μmol/L vs179.62 μmol/L, P=0.001), lower complement C3 values (0.36 g/L vs0.74 g/L, P<0.001) at biopsy, and less severe pathological chronic lesions compared with the N-PIGN group. In the N-PIGN subgroup analysis, the C3-dominant-deposition group had higher creatinine values (235.30 μmol/L vs106.70 μmol/L, P=0.004) and higher 24-hour urine protein values (4 025.62 mg vs1 981.11 mg, P=0.037) than the C3-alone-deposition group. The prognosis of kidney in the PIGN group (P=0.049), the C3-alone-deposition group (P=0.017), and the C3G group (P=0.018) was better than that in the N-PIGN group, the C3-dominant-deposition group, and the N-C3G group, respectively.
CONCLUSIONS: Glomerulonephritis with dominant C3 covers a variety of pathological types, and PIGN needs to be excluded before diagnosing C3G because of considerable overlap with atypical PIGN and C3G; in addition, the deposition of C1q complement under fluorescence microscope may indicate poor renal prognosis, and relevant diagnosis, treatment, and follow-up should be strengthened.
目的: 随着对补体失调研究的深入,以C3沉积为主的肾小球肾炎日益受到关注,其病理类型多样,且病理类型间症状及预后差异具有异质性。为避免误诊及漏诊,本研究分析不同病理类型C3沉积为主的肾小球肾炎的临床、病理及预后特点。方法: 回顾性分析52例2013年6月至2022年10月行肾活检诊断为以C3沉积为主肾小球肾炎患者的临床、病理及随访资料。根据临床表现以及病理检查结果分为感染后肾小球肾炎(post-infectious glomerulonephritis,PIGN)组(n=15)和非感染后肾小球肾炎(non-post-infectious glomerulonephritis,N-PIGN)组(n=37)。进一步行N-PIGN亚组分析,分为C3独立沉积组(n=16)与C3复合沉积组(n=21),或C3肾病(C3 glomerulopathy,C3G)组(n=27)与非C3肾病(N-C3G)组(n=10)。结果: PIGN组相较于N-PIGN组,活检时血清肌酐值更低(84.60 μmol/L vs 179.62 μmol/L,P=0.001),补体C3值更低(0.36 g/L vs0.74 g/L,P<0.001),病理慢性化病变程度更轻。在N-PIGN亚组分析中,C3复合沉积组较C3独立沉积组血清肌酐值更高(235.30 μmol/L vs106.70 μmol/L,P=0.004),24 h尿蛋白值更高(4 025.62 mg vs1 981.11 mg,P=0.037)。PIGN组的预后好于N-PIGN组(P=0.049),C3独立沉积组的预后好于C3复合沉积组(P=0.017),C3G组的预后好于N-C3G (P=0.018)。结论: C3沉积为主的肾小球肾炎涵盖多种病理类型,诊断C3G前需先排除PIGN,但对于非典型PIGN患者仍需要警惕C3G叠加或者相互转化;此外,荧光显微镜下经典补体C1q的沉积可能提示肾预后不良,应加强相关诊治与随访。.