Beltrão Marília, Bodas Abilia, Azevedo Fernando, Nunes Amadeu, Santos Carlos, Delgado Luís
Serviço e Laboratório de Imunologia, Faculdade de Medicina da Universidade do Porto, Porto.
Acta Med Port. 2010 Sep-Oct;23(5):829-36. Epub 2010 Oct 22.
The incidence of inflammatory bowel disease (IBD) has been increasing worldwide, and despite the advances regarding their pathogenesis and therapeutics, the differential diagnosis between Crohn's Disease (CD) and Ulcerative Colitis (UC) is mainly based on clinically invasive tests. Recent studies have identified new serological markers with a potential value for the diagnosis of these pathologies, in particular the anti-Saccharomyces cerevisiae antibodies (ASCA) and anti-neutrophil cytoplasmic antibodies (ANCA). Also of note are the anti-goblet cells antibodies (anti-CCI) and the anti-pancreatic exocrine autoantibodies that react with the pancreatic acinus (anti-AP). We assessed these new serological markers and compared the efficiency between immune enzymatic (ELISA) and indirect immunofluorescence tests in the identification of ASCA of IgG or IgA class. We studied a set of 81 serum samples (with an initial diagnosis of IBD) and 33 control samples from healthy blood donors. The laboratory tests were correlated with the diagnosis of each patient, established in the Gastroenterology outpatient unit based on conventional methods. The agreement between the two laboratory methods employed in the identification of the ASCA was excellent (k = 0.63) for the IgG antibodies and good (k = 0.56) for the IgA antibodies. We found a weak agreement (k = 0.137) between ELISA (MPO and PR3 purified antigens) and the IFA test for ANCA. Regarding the serologic markers ANCA, anti-AP and anti-CCI, only the later showed no differences in the distribution of positive results between the studied groups. Positive ASCA IgG and IgA were significantly associated with diagnosis of DC, with both laboratorial methods tested. The identification of ANCA with the available solidphase tests does not seem appropriate for the screening of the autoantibodies with the atypical p-ANCA pattern of IBD. The combination between anti-AP and ASCA antibodies seems a good option for the laboratorial diagnosis of CD. This study shows that these serologic markers in spite of being non invasive laboratory tests, also have a considerable overlapping in the different IBD. Nevertheless, further prospective studies based on larger populations are required to clarify the relationship between these antibodies, the diagnosis and clinical evolution of inflammatory bowel disease.
炎症性肠病（IBD）在全球范围内的发病率一直在上升，尽管在其发病机制和治疗方面取得了进展，但克罗恩病（CD）和溃疡性结肠炎（UC）之间的鉴别诊断主要基于临床侵入性检查。最近的研究已经确定了对这些疾病诊断具有潜在价值的新血清学标志物，特别是抗酿酒酵母抗体（ASCA）和抗中性粒细胞胞浆抗体（ANCA）。同样值得注意的是抗杯状细胞抗体（抗CCI）和与胰腺腺泡发生反应的抗胰腺外分泌自身抗体（抗AP）。我们评估了这些新的血清学标志物，并比较了免疫酶法（ELISA）和间接免疫荧光试验在鉴定IgG或IgA类ASCA方面的效率。我们研究了一组81份血清样本（初步诊断为IBD）和33份来自健康献血者的对照样本。实验室检测结果与每位患者的诊断相关，该诊断是在胃肠病科门诊基于传统方法确定的。在鉴定ASCA时，所采用的两种实验室方法之间的一致性对于IgG抗体而言极佳（k = 0.63），对于IgA抗体而言良好（k = 0.56）。我们发现ELISA（MPO和PR3纯化抗原）与ANCA的免疫荧光法检测之间的一致性较弱（k = 0.137）。关于血清学标志物ANCA、抗AP和抗CCI，只有后者在研究组之间的阳性结果分布上没有差异。经两种实验室方法检测，ASCA IgG和IgA阳性均与CD诊断显著相关。用现有的固相试验鉴定ANCA似乎不适用于筛查具有IBD非典型p-ANCA模式的自身抗体。抗AP和ASCA抗体的联合似乎是CD实验室诊断的一个不错选择。本研究表明，这些血清学标志物尽管属于非侵入性实验室检测，但在不同的IBD中也存在相当大的重叠。然而，需要基于更大人群的进一步前瞻性研究来阐明这些抗体与炎症性肠病的诊断和临床进展之间的关系。
