并发肾脏中等动脉受累的显微镜下型多血管炎的临床病理特点

Clinicopathological characteristics of microscopic polyangiitis with medium renal artery involvement

目的 探讨并发肾脏中等动脉受累的显微镜下型多血管炎（ＭＰＡ）的临床与病理特点。方法 对近两年在我院经肾脏病理确诊的ＭＰＡ进行分析总结，并比较有无并发肾脏中等动脉受累病例的临床及病理特点。结果３２例ＭＰＡ患者中７例并发中等动脉受累。２５例无中等动脉受累者，均有新月体形成，其中新月体肾炎１９例，局灶节段型坏死性肾小球肾炎９例；２１例表现为急性肾功能衰竭（ＡＲＦ），平均病程１０周；治疗后８例完全缓解。７例并发中等动脉受累者，弓状动脉大分支节段性纤维素样坏死，肾小球缺血改变突出，但新月体病变轻，无１例新月体肾炎；６例表现为ＡＲＦ，平均病程４周；治疗后５例完全缓解。两组比较，合并中等动脉受累者病程短（Ｐ＜０．０５），发生ＡＲＦ者达新月体肾炎者少（Ｐ＜０．０１），经强化免疫抑制治疗后多可完全缓解（Ｐ＜０．０５）。结论 ＭＰＡ中约２０％同时累及肾脏中等动脉，因中等动脉病变引起广泛肾缺血，故ＡＲＦ起病急，进展快，及时治疗则预后相对较好。

Objective To study the clinical and pathological characteristics of microscopic polyangiitis(MPA) with renal medium artery involvement. Methods Hospitalized patients with MPA in recent two years were reviewed retrospectively and their clinicopathological features were compared between patients with and without renal medium artery involvement. Results 32 MPA patients were confirmed by renal biospy. Seven cases were with renal medium artery involvement and 25 cases were without renal medium artery involvement. Of these 25 cases, all had crescent formation and 19 fulfilled the diagnosis of crescentic glomerulonephntis, 9 of focal segmental necrosis glomerulonephritis; 21/25 patients had acute renal failure with an average course of 10 weeks; 8 out of 21 cases achieved complete remission after treatment. Seven MPA patients with renal medium artery involvement presented segmental fibrinoid necrosis of the major branch of arcuate artery; the glomerular ischemia was predominant, but crescentic lesions were mild, none of them had crescentic glomerulonephritis; 6 patients had acute renal failure with an average course of 4 weeks, 5 out of 6 cases achieved complete remission after treatment. In comparison, MPA with renal medium artery involvement had a shorter course(P <0. 05), less crescentic glomerulonephritis in ARF(P <0. 01) and more patients achieved complete remission from ARF after intensive immunosuppressive therapy(P <0. 05) Conclusions About 20% of MPA patients have renal medium artery involvement. Because of extensive renal ischemia, these patients proceed to ARF faster and respond to therapy better.