Braun A, Sis J, Max R, Mueller K, Fiehn C, Zeier M, Andrassy K
Department of Internal Medicine I (Nephrology), University Hospital of Heidelberg, Germany.
Scand J Rheumatol. 2007 Jul-Aug;36(4):291-8. doi: 10.1080/03009740701218717.
To evaluate the prevalence, sensitivity, and specificity of anti-chromatin and anti-C1q antibodies in systemic lupus erythematosus (SLE) and lupus nephritis compared to small vessel vasculitis and other connective tissue diseases. To provide long-term follow-up data for anti-chromatin antibodies in lupus nephritis.
We determined the significance of anti-nuclear antibodies (ANA), anti- double-stranded DNA (anti-dsDNA), anti-chromatin, and anti-C1q antibodies, as well as complement factors C3 and C4, in relation to disease activity in SLE patients with (n = 47; long-term follow-up data for 33 patients) and without (n = 31) biopsy-confirmed lupus nephritis, microscopic polyangiitis (n = 37), Wegener's granulomatosis (n = 66), primary Sjögren's syndrome (n = 17), limited scleroderma (CREST syndrome) (n = 6), and progressive systemic scleroderma (PSS) (n = 11).
Anti-chromatin antibodies were more specific and sensitive than anti-C1q antibodies in distinguishing SLE patients from those with other systemic autoimmune diseases [anti-chromatin: sensitivity 64.1%, specificity 99.2%, odds ratio (OR) 219.6; anti-C1q: sensitivity 50%, specificity 72.6%, OR 2.65]. Anti-C1q antibodies were present in 75% of patients with Sjögren's syndrome and 35.1% of patients with microscopic polyangiitis. Anti-chromatin antibodies could identify SLE in patients with positive ANA but negative anti-dsDNA antibodies. Persisting anti-chromatin antibodies indicated SLE disease activity, even if anti-dsDNA antibodies had become negative. In long-term follow-up, those SLE patients with negative anti-dsDNA antibodies but persisting ANA and anti-chromatin antibodies relapsed if immunosuppression had been tapered. Anti-chromatin antibodies correlated with the SLE disease activity index (SLEDAI) as a marker of disease activity.
The measurement of anti-chromatin, but not anti-C1q, antibodies in patients with systemic autoimmune diseases increases diagnostic sensitivity and specificity for SLE and assists in treatment decisions in anti-dsDNA-negative patients.
与小血管炎和其他结缔组织疾病相比，评估抗染色质抗体和抗C1q抗体在系统性红斑狼疮（SLE）和狼疮性肾炎中的患病率、敏感性和特异性。提供狼疮性肾炎中抗染色质抗体的长期随访数据。
我们测定了抗核抗体（ANA）、抗双链DNA（抗dsDNA）、抗染色质和抗C1q抗体以及补体因子C3和C4在有（n = 47；33例患者的长期随访数据）和无（n = 31）活检确诊的狼疮性肾炎、显微镜下多血管炎（n = 37）、韦格纳肉芽肿（n = 66）、原发性干燥综合征（n = 17）、局限性硬皮病（CREST综合征）（n = 6）和进行性系统性硬皮病（PSS）（n = 11）的SLE患者中的疾病活动相关性。
在区分SLE患者与其他系统性自身免疫性疾病患者方面，抗染色质抗体比抗C1q抗体更具特异性和敏感性[抗染色质：敏感性64.1%，特异性99.2%，优势比（OR）219.6；抗C1q：敏感性50%，特异性72.6%，OR 2.65]。抗C1q抗体在75%的干燥综合征患者和35.1%的显微镜下多血管炎患者中存在。抗染色质抗体可在ANA阳性但抗dsDNA抗体阴性的患者中识别SLE。持续存在的抗染色质抗体表明SLE疾病活动，即使抗dsDNA抗体已变为阴性。在长期随访中，如果免疫抑制逐渐减少，那些抗dsDNA抗体阴性但ANA和抗染色质抗体持续存在的SLE患者会复发。抗染色质抗体与作为疾病活动标志物的SLE疾病活动指数（SLEDAI）相关。
在系统性自身免疫性疾病患者中检测抗染色质抗体而非抗C1q抗体可提高SLE的诊断敏感性和特异性，并有助于抗dsDNA阴性患者的治疗决策。
