He Ronghua, Ma Mingqi, Luo Ping, Guo Qiaoyan
Department of Gastroenterology, The Second Hospital of Jilin University, Changchun, Jilin, 130041, China.
Department of Nephrology and Rheumatology, The Second Hospital of Jilin University, Changchun, Jilin, 130041, China.
Clin Rheumatol. 2023 May;42(5):1459-1467. doi: 10.1007/s10067-022-06493-5. Epub 2023 Jan 3.
Because of some similarities in organ involvement, clinical manifestations, and histopathological features, IgG4-related disease (IgG4-RD) may occur concurrently with some clinicopathologic variants of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). An overlap syndrome of IgG4-RD and AAV has recently been proposed in clinical and/or histopathological studies, indicating that there may be some potential pathophysiological associations between the two disease entities; however, the mechanisms underlying these are incompletely understood. Here, we describe a rare case of a 63-year-old man with IgG4-related tubulointerstitial nephritis (IgG4-TIN) and microscopic polyangiitis-associated glomerulonephritis (MPA-GN) overlap syndrome. The clinical diagnosis of MPA was based on the 2022 American College of Rheumatology (ACR)/European League Against Rheumatology (EULAR) classification criteria. Remission induction therapy with intravenous methylprednisolone was initiated, followed by oral prednisone maintenance therapy with gradual tapering. The patient remained asymptomatic and his renal function was essentially normalized within 3.5 months of follow-up. The serum IgG4 levels decreased to 5 g/L. We also conducted a literature review to identify clinical findings, treatment options, and outcomes of patients with concurrent IgG4-RD and MPA and briefly discussed the potential pathophysiological association between IgG4-RD and MPA. Our findings enrich the database of this rare overlap syndrome and provide a basis for the diagnosis and early intervention in both diseases. These results provide some insights for clinicians to recognize and treat this overlap syndrome.
由于在器官受累、临床表现和组织病理学特征方面存在一些相似性，IgG4相关疾病（IgG4-RD）可能与抗中性粒细胞胞浆抗体（ANCA）相关血管炎（AAV）的某些临床病理变体同时发生。最近在临床和/或组织病理学研究中提出了IgG4-RD和AAV的重叠综合征，这表明这两种疾病实体之间可能存在一些潜在的病理生理关联；然而，其潜在机制尚未完全明确。在此，我们描述了一例罕见的63岁男性患者，其患有IgG4相关肾小管间质性肾炎（IgG4-TIN）和显微镜下多血管炎相关性肾小球肾炎（MPA-GN）重叠综合征。MPA的临床诊断基于2022年美国风湿病学会（ACR）/欧洲抗风湿病联盟（EULAR）分类标准。开始采用静脉注射甲泼尼龙进行诱导缓解治疗，随后采用口服泼尼松维持治疗并逐渐减量。患者保持无症状，在随访3.5个月内肾功能基本恢复正常。血清IgG4水平降至5g/L。我们还进行了文献综述，以确定IgG4-RD和MPA并发患者的临床发现、治疗选择和结果，并简要讨论了IgG4-RD和MPA之间潜在的病理生理关联。我们的研究结果丰富了这种罕见重叠综合征的数据库，并为这两种疾病的诊断和早期干预提供了依据。这些结果为临床医生识别和治疗这种重叠综合征提供了一些见解。
