Clinicopathological characteristics and prognosis of idiopathic membranous nephropathy with or without C3 deposition / 中华全科医师杂志

ABSTRACT

Objective:To investigate the clinicopathological characteristics and prognosis of idiopathic membranous nephropathy (IMN) with or without C3 deposition.Methods:Clinical and pathological data of 576 patients with IMN diagnosed in Affiliated Hospital of Qingdao University from January 2017 to January 2021 were retrospectively analyzed. The patients were divided into C3 deposition group and non-C3 deposition group according to the immunofluorescence staining of C3. The clinical and pathological characteristics were compared between the two groups. Kaplan-Meier survival curve was used to compare the prognosis of the two groups.Results:A total of 576 IMN patients (male 364 (63.20%)) were enrolled, including 400 patients (69.44%) with C3 deposition and 176 patients (30.56%) without C3 deposition. Compared with the non-C3 deposition group, the levels of total blood cholesterol ( t=0.94, P=0.002) and the proportion of phospholipase A2 receptor ( χ2=9.99, P=0.002), IgG ( χ2=10.67, P=0.001), IgM ( χ2=7.00, P=0.008), IgA ( χ2=7.87, P=0.005) and C1q ( χ2=8.28, P=0.004) depositions in renal tissues was higher in C3 deposition group, while the levels of serum C3 ( t=2.87, P=0.004), albumin ( t=3.57, P<0.001) and IgG ( Z=3.55, P<0.001) were lower in C3 deposition group. There were no significant differences in other clinicopathological indicators between the two groups. The survival analysis was performed in 460 patients who were followed for>6 months, including 319 cases (69.35%) of C3 deposition and 141 cases (30.65%) of non-C3 deposition. The end point event was defined as an eGFR decline>30% or entry into end stage renal disease (ESRD). There was no statistically significant difference in treatment method between the two groups ( P>0.05). The median follow-up time was 22 (13,32) months, 327 (71.09%) patients achieved remission, and 22 patients had renal end-point events. Compared with the non-C3 deposition group, the proportion of urinary protein remission was lower ( χ2=10.85, P<0.05), the incidence of renal end-point events was higher ( χ2=5.05, P<0.05). Kaplan-Meier survival analysis showed that patients with C3 deposition had a lower cumulative remission rate (Log-rank χ2=6.68, P=0.010), and a lower cumulative renal survival than those without C3 deposition had ( χ2=5.42, P=0.020). Conclusions:Compared with patients without C3 deposition, IMN patients with C3 deposition have more severe clinical and pathological changes, lower renal cumulative remission rate, and are more likely to have poor prognosis.