低IgG3或低IgG4患者发生狼疮肾炎的几率更高

作者：Perazzio SF，et al.

翻译：邓晓莉 校正：张警丰

摘要：目的：研究在狼疮以及具有相关临床特点患者中免疫缺陷样状态的患病率。

方法：研究共纳入315例狼疮患者以及301例对照患者，分析其C4A、C4B基因拷贝数、免疫球蛋白同种型、IgG亚型、CH50、C2、C3以及中性粒细胞氧化爆发。如果存在C2、C3降低的情况则还要对C2和C3基因进行测序。CH50不正常而C2以及C3正常的患者还要进行C1q-C9的检测。狼疮病情活动并且存在异常结果的患者在除外了疾病复发的情况下再重新检测前述指标，不能达到疾病缓解的患者被排除在外。15名患者因此被排除在外。持续异常的结果提示免疫缺陷样状态。

结果：与对照组相比，狼疮患者免疫缺陷样状态的发生率显著升高(28.7% vs 3.3%; P<0 .001)，尤其是低免疫球蛋白血症。严格的检测确定狼疮患者中仅2例是c2缺陷基因的携带者。与对照组相比，有更多的狼疮患者拥有小于2个拷贝数的c4a基因。狼疮患者低igg2、igg3、igg4以及igm的发生率更高。低igg3或者低igg4的患者中狼疮肾炎的发病率更高。低igm的患者病程更长、发病年龄更大、口腔溃疡的发病率更低。

结论：免疫缺陷样状态在相当一部分狼疮患者中存在。需要进一步的研究来确定这些免疫缺陷状态的影响，以及这些状态是原发的还是继发于狼疮本身等混杂因素。

附原文：OBJECTIVE: To determine the frequency of immunodeficiency-like states in SLE and related clinical features. METHODS: Three hundred and fifteen SLE patients and 301 controls were evaluated for C4A and C4B gene copy number, immunoglobulin isotypes, IgG subclasses, total haemolytic complement (CH50), C2, C3 and neutrophil oxidative burst. C2 and C3 genes were sequenced in cases of low

C2 or C3 levels. Those presenting abnormal CH50 with normal C2 and C3 underwent C1q-C9 determination. Patients with active SLE and abnormal results were re-tested after the flare or were excluded if no remission was attained. Fifteen patients were excluded on this basis. Persistent abnormal results characterized an immunodeficiency-like state. RESULTS: A significantly higher percentage of SLE patients presented an immunodeficiency-like state compared with controls (28.7% vs 3.3%; P < 0.001), especially low immunoglobulin serum levels. rigorous testing confirmed only two cases of c2 deficiency carriers among the sle patients. there were significantly more sle patients with less than two c4a copies compared with controls. sle patients had higher frequency of low igg2, igg3, igg4 and igm levels compared with controls. patients with low igg3 or igg4 presented higher frequency of lupus nephropathy. patients with low igm had longer disease duration, older age at sle onset and lower frequency of oral ulcers. conclusion: an immunodeficiency-like state is present in a sizable fraction of sle patients. further studies are warranted to determine the impact of these immunodeficiency states and whether they are a primary condition or are secondary to confounding factors, including sle itself. 引自：perazzio sf, granados á, salom?o r, et al. high frequency of immunodeficiency-like states in systemic lupus erythematosus: a cross-sectional study in 300 consecutive patients. rheumatology (oxford). 2016 sep;55(9):1647-55.