Ebbo Mikael, Grados Aurélie, Bernit Emmanuelle, Vély Frederic, Boucraut José, Harlé Jean-Robert, Daniel Laurent, Schleinitz Nicolas
Université de la Méditerranée Aix-Marseille II, France.
Int J Rheumatol. 2012;2012:602809. doi: 10.1155/2012/602809. Epub 2012 Aug 26.
Statement of Purpose. IgG4-related disease (IgG4-RD) is usually associated to an increase of serum IgG4 levels. However other conditions have also been associated to high serum IgG4 levels. Methods. All IgG subclasses analyses performed in our hospital over a one-year period were analyzed. When IgG4 level were over 1.35 g/L, the patient's clinical observation was analyzed and both final diagnosis and reason leading to IgG subclasses analysis were recorded. Only polyclonal increases of IgG4 were considered. Summary of the Results. On 646 IgG subclass analysis performed, 59 patients had serum IgG4 over 1.35 g/L. The final diagnosis associated to serum IgG4 increase was very variable. Most patients (25%) presented with repeated infections, 13.5% with autoimmune diseases, and 10% with IgG4-RD. Other patients presented with cancer, primary immune deficiencies, idiopathic interstitial lung disease, cystic fibrosis, histiocytosis, or systemic vasculitis and 13.5% presented with various pathologies or no diagnosis. Mean IgG4 levels and IgG4/IgG ratio were higher in IgG4-RD than in other pathologies associated to elevated IgG4 levels. Conclusions. Our study confirms that elevation of serum IgG4 is not specific to IgG4-RD. Before retaining IgG4-RD diagnosis in cases of serum IgG4 above 1.35 g/L, several other pathological conditions should be excluded.
目的声明。IgG4相关疾病（IgG4-RD）通常与血清IgG4水平升高有关。然而，其他情况也与高血清IgG4水平有关。方法。对我院在一年时间内进行的所有IgG亚类分析进行了分析。当IgG4水平超过1.35g/L时，分析患者的临床观察情况，并记录最终诊断结果以及进行IgG亚类分析的原因。仅考虑IgG4的多克隆升高情况。结果总结。在进行的646次IgG亚类分析中，59例患者的血清IgG4超过1.35g/L。与血清IgG4升高相关的最终诊断差异很大。大多数患者（25%）表现为反复感染，13.5%患有自身免疫性疾病，10%患有IgG4-RD。其他患者患有癌症、原发性免疫缺陷、特发性间质性肺病、囊性纤维化、组织细胞增多症或系统性血管炎，13.5%的患者表现为各种病症或未明确诊断。IgG4-RD患者的平均IgG4水平和IgG4/IgG比值高于与IgG4水平升高相关的其他病症。结论。我们的研究证实，血清IgG4升高并非IgG4-RD所特有。在血清IgG4高于1.35g/L的病例中确定IgG4-RD诊断之前，应排除其他几种病理状况。
