摘要 ：

目的：通过队列研究，探讨原发干燥综合征(SS)患者的IgG4水平是否与不同的临床表现、血清学和组织病理学特征有关。

方法：测定133名原发SS患者和49名健康对照者(HD)的血清IgG4水平。74名狼疮患者和54名类风湿关节炎(RA)患者作为疾病对照。在石蜡包埋的小唾液腺(MSG)组织中进行免疫组化IgG4分析。

结果：在133例SS患者(高IgG4组)中有10例(7.5%)检测到IgG4血清水平升高(> 135mg / dl)，74例狼疮患者中有8例(10.8%)，54例RA患者中有7例(12.9%)，49名健康对照中有1例(2%)血清IgG4水平升高。与正常IgG4(<135mg/ dl)SS组相比，高IgG4患者的IgG4相关特征(自身免疫性胆管炎，自身免疫性胰腺炎和间质性肾炎)的患病率增加，抗核抗体阳性率、IgG2和IgE水平降低。在6个高IgG4组中的MSG组织中进行IgG4浆细胞阳性染色，有3个检测到IgG4/IgG比率≥40%。队列中133名研究对象有10例(7.5%)符合IgG4相关疾病(IgG4-RD)的标准。

结论：7.5%原发SS患者的血清IgG4水平升高，并有IgG4-RD的临床表现、血清学和组织病理学特征。这种高IgG4水平SS分组作为IgG4-RD的一种分类或SS的亚型分组是否合理在将来的研究中还有待进一步探讨。

附原文：

Objectives:To determine IgG4 levels in a cohort ofconsecutive patients with primary Sjögren's syndrome (SS) and other autoimmunediseases and explore whether they associate with distinct clinical, serologic,and histopathologic features.

Methods:Serum IgG4 levels were measured in 133 primarySS patients and 49 healthy donors (HDs). Seventy-four lupus and 54 rheumatoidarthritis (RA) patients served as disease controls. Immunohistochemical IgG4analysis was performed in paraffin-embedded minor salivary gland (MSG) tissues.

Results:Raised IgG4 serum levels (>135mg/dl) weredetected in 10 (7.5%) of 133 primary SS patients (high-IgG4 group), in 8(10.8%) of 74 lupus patients, in 7 (12.9%) of 54 RA patients, and in 1 (2%) of49 HDs. Compared to the normal-IgG4 (<135mg/dl) primary SS group, high-IgG4patients exhibited increased prevalence of IgG4-related features (autoimmunecholangitis, autoimmune pancreatitis, and interstitial nephritis), lower ratesof antinuclear antibody positivity, and higher IgG2 and IgE levels. Positivestaining for IgG4+ plasma cells with an IgG4: IgG ratio≥ 40% was detected in 3 of 6 available MSG tissues in the high-IgG4group. Criteria of possible or definite IgG4-related disease (IgG4-RD) werefulfilled by 10 (7.5%) of 133 of our primary SS cohort.

Conclusion:RaisedIgG4 serum levels were detected in 7.5% of primary SS patients in associationwith IgG4-RD-reminiscent clinical, serologic, and histopathologic features.Whether this high-IgG4 primary SS group represents a misclassified IgG4-RDgroup or a distinct primary SS subtype remains to be further exploredin future studies.

引自：Mavragani CP, Fragoulis GE, Dontogianni D, etal.ElevatedIgG4 serum levels among primary Sjögren's Syndrome patients: do they unmaskunderlying IgG4-related disease? Artheitis Care & Research, 2014, 66(5):773-777. DOI: 10.1002/acr. 22216.