显微镜型多血管炎肾活检病例的临床病理分析

Clinicopathologic analysis of 34 patients with microscopic polyangitis

目的探讨血清抗中性粒细胞胞质抗体(ANCA)及肾小球内有无免疫球蛋白(Ig)沉积在显微镜型多血管炎(MPA)肾活检病例中的病理诊断价值及其临床病理意义。方法 34例 MPA 均为该系2000年1月至2007年3月7年间的就诊患者,其临床资料比较完整,后经。肾穿刺活检而确诊者,分别对其血清 ANCA 阳性和阴性及。肾小球内有无 Ig 沉积的临床病理特点进行比较。结果 34例MPA 患者,约1/5～1/2病例伴有各种肾外症状;经血清 ANCA 检测,阳性者26例(76.5%);阴性者8例(23.5%);其尿蛋白多呈轻～中度,呈。肾病综合征者仅3例;肾功能减退者32例。经病理检查显示,24例为新月体性。肾炎,8例为局灶节段性肾炎,其他类型者仅2例;伴肾血管坏死或内膜炎症7例,内膜增厚24例;伴间质炎性细胞浸润29例,其中21例伴有中性粒细胞浸润。经临床与病理比较分析,发现 ANCA 阳性组的新月体形成率显著高于 ANCA 阴性组(P<0.05);在26例 ANCA 阳性组病例中,肾小球 Ig 沉积者的尿蛋白定量显著高于无 Ig 沉积组(P<0.05),其中1例合并 IgA 肾病。结论对 MPA 的诊断有赖于对患者血清 ANCA 的检测和肾活检组织的病理学检查;ANCA 是促进肾小球新月体形成的一个重要因素;Ig 在肾小球内的沉积对患者蛋白尿的加重起促进作用。

Objective To study the clinicopathologic features of microscopic polyangitis （ MPA）, and to compare the differences in anti-neutrophil cytoplasmic autoantibody （ ANCA）-positive and ANCA- negative patients, as well as in ANCA-positive cases with or without glomerular immunoglobulin deposition. Methods Thirty-four biopsy-proven cases of MPA were retrieved from the archival files of the Department during the past 7 years. The clinicopathologic characteristics between ANCA-positive and negative patients, as well as between ANCA-positive cases with and without glomerular immunoglobulin deposition, were compared. Results Amongst the 34 MPA patients studied, about one-fifth to one-half were accompanied by various extrarenal symptoms. Serum ANCA was positive in 26 patients （76. 5% ）. A slight to moderate increase in urinary protein was demonstrated in 31 patients, while 3 patients had nephrotic syndrome. Elevated serum creatinine was detected in 32 cases. Renal biopsy revealed crescentic glomerulonephritis in 24 cases, focal segmental glomerulonephritis in 8 cases, vascular fibrinoid necrosis with inflammation in 7 cases, intimal thickening of arterioles in 24 cases, interstitial inflammatory cells, including neutrophil infiltration （21 cases）, in 29 cases. Crescentic formation was more common in the ANCA-positive group than in the ANCA-negative group （P 〈 0.05）. Amongst the 26 ANCA-positive cases, 10 had glomerular immunoglobulin deposits （including 1 case with IgA nephropathy）. In general, these cases had a greater degree of proteinuria than those without glomerular immunoglobulin deposits （ P 〈 0.05 ）. Conclusions The diagnosis of MPA relies on histologic examination of renal biopsy and clinicopathologic correlation. Serum ANCA seems important for glomerular crescent formation. Glomerular immunoglobulin deposition may also play a significant role in the exacerbation of proteinuria.