Feki S, Frikha F, Ben Hadj Hmida Y, Abed S, Ben Ayed M, Turki H, Hachicha J, Baklouti S, Bahloul Z, Masmoudi H
Laboratoire d'immunologie, CHU Habib Bourguiba, 3029 Sfax, Tunisie.
Rev Med Interne. 2012 Sep;33(9):475-81. doi: 10.1016/j.revmed.2012.04.017. Epub 2012 May 30.
The objective of this study was to determine the clinical relevance and the diagnostic significance of positive antinuclear antibodies (ANA) without identified antigenic target by the usual characterization technique.
Retrospective study conducted in the Laboratory of Immunology of Habib Bourguiba Hospital (Sfax, Tunisia) during 18 months. The inclusion criteria were the presence of an ANA titer greater or equal to 1/320 with negative characterization result. ANA screening was performed by indirect immunofluorescence (IIF) on Hep2 cells. Each positive serum was tested by IIF on Crithidia luciliae (anti-native DNA) and by immunodot (anti-nucleosome, anti-histone, anti-Sm, anti-RNP, anti-SSA, anti-SSB, anti-Scl 70, anti-PM-Scl, anti-Jo1, anti-PCNA and anti-ribosomal protein). Sera of systemic lupus erythematosus (SLE), myositis, and scleroderma patients were tested for anti-Ku, anti-PL7, anti-PL12 and anti-Ro-52 using dot myositis.
Sera of 90 patients were studied: 18 men and 72 women (average age: 44 years). Drug-induced ANA was found in eight patients. The most frequent clinical symptoms were joint (56.7%), cutaneous (54.4%) and constitutional symptoms (45.6%). The diagnosis of an autoimmune disease was suspected in 49 patients (54.5%) and confirmed in 30 (33.3%) including 20 cases of connective tissue disease: myositis (n=6), scleroderma (n=5), Sjögren's syndrome (n=3), SLE (n=4), rheumatoid arthritis (n=6) and antiphospholipid syndrome (n=4). Other autoimmune diseases were less frequent. The anti-Ku antibody was detected in the majority of patients with connective tissue disease. The diagnosis of non-autoimmune diseases was established in 25.5% of patients. Eighteen patients (20%) had no diagnosis orientation.
Our study demonstrated the diagnostic value of the presence of ANA even in the absence of known antigenic target, confirmed the role of the IIF as "gold standard" test for ANA screening, and suggested the usefulness of the addition of Ku antigen in the immunodot classic profile.
本研究的目的是确定通过常规鉴定技术未鉴定出抗原靶点的抗核抗体（ANA）阳性的临床相关性和诊断意义。
在哈比卜·布尔吉巴医院（突尼斯斯法克斯）免疫实验室进行了为期18个月的回顾性研究。纳入标准为ANA滴度大于或等于1/320且鉴定结果为阴性。通过间接免疫荧光法（IIF）在人喉癌上皮细胞（Hep2）上进行ANA筛查。每份阳性血清通过IIF检测利什曼原虫（抗天然DNA），并通过免疫斑点法检测（抗核小体、抗组蛋白、抗Sm、抗核糖核蛋白、抗干燥综合征A抗原、抗干燥综合征B抗原、抗Scl 70、抗PM-Scl、抗Jo1、抗增殖细胞核抗原和抗核糖体蛋白）。对系统性红斑狼疮（SLE）、肌炎和硬皮病患者的血清使用斑点肌炎法检测抗Ku、抗PL7、抗PL12和抗Ro-52。
研究了90例患者的血清：18例男性和72例女性（平均年龄：44岁）。在8例患者中发现药物性ANA。最常见的临床症状为关节症状（56.7%）、皮肤症状（54.4%）和全身症状（45.6%）。49例患者（54.5%）怀疑患有自身免疫性疾病，30例（33.3%）确诊，其中包括20例结缔组织病：肌炎（n = 6）、硬皮病（n = 5）、干燥综合征（n = 3）、SLE（n = 4）、类风湿关节炎（n = 6）和抗磷脂综合征（n = 4）。其他自身免疫性疾病较少见。在大多数结缔组织病患者中检测到抗Ku抗体。25.5%的患者确诊为非自身免疫性疾病。18例患者（20%）未明确诊断方向。
我们的研究证明了即使在没有已知抗原靶点的情况下ANA存在的诊断价值，证实了IIF作为ANA筛查“金标准”检测的作用，并表明在免疫斑点经典检测项目中增加Ku抗原的有用性。
