Data from: Autoantibody prevalence in active tuberculosis: reactive or pathognomonic?

Objectives: To evaluate the autoantibody in patients without corresponding symptoms, whether these autoantibody are pathognomonic or not. We hypothesised that autoantibody may be reactive to chronic infection, such as tuberculosis (TB). Design: Randomised, case–control cohort study. Setting: A tertiary centre in Taiwan. Participants: We randomly chose 100 patients out of the data bank of patients with TB in a tertiary medical centre. All patients completed the sera sampling. We chose 100 patients according to autoantibody prevalence in previous literature. We also chose 100 medical staff as control group. Interventions: We tested anti-SSA, anti-SSB, anti-Sm, anti ribonucleoprotein, anti-Scl 70, anticentromere, anti-double-stranded DNA, anticardiolipin IgG and IgM in all patient and control groups. The clinical symptoms and the underlying disease were all recorded. Primary and secondary outcome measures: The result of sera antibody titre was recorded. For those with specific positive serology results, following examination was carried out after a 3-month anti-TB medication. Results: Anticardiolipin IgG titre was significantly higher in patients with TB than in control group. We compared the result with previous population study and found that anti-Scl70 is also significantly higher in patients with TB. The following up data in anti-Scl70 revealed decreased titre after treatment. No correlation between sera titre and clinical conditions was observed. Conclusions: In TB endemic areas, a significant proportion (32%) of patients with TB have elevated autoantibody titres, especially anticardiolipin IgG and anti-Scl-70. Mycobacterial studies should be performed in patients with elevated serum autoantibody titres but without the typical or multiple manifestations of autoimmune diseases. Trial registration: The study was approved by the Institutional Review Board of the hospital (NTUH REC: 9561707008) after informed consent had been obtained from the patients.

研究目的（Objectives）：评估无对应临床症状患者体内的自身抗体（autoantibody）是否为特征性诊断标志物或具有致病性。我们提出假说：自身抗体可能对慢性感染产生应答，例如结核（TB）。
研究设计（Design）：随机化病例对照队列研究。
研究地点（Setting）：中国台湾某三级医疗中心。
研究对象（Participants）：我们从某三级医疗中心的结核患者数据库中随机选取100名完成血清采样的患者；依据既往文献报道的自身抗体患病率选取100名对照个体，同时选取100名医护人员作为对照组。
干预措施（Interventions）：对所有研究对象及对照组人群检测抗SSA（anti-SSA）、抗SSB（anti-SSB）、抗Sm（anti-Sm）、抗核糖核蛋白（anti ribonucleoprotein）、抗Scl-70（anti-Scl 70）、抗着丝粒抗体（anticentromere）、抗双链DNA（anti-double-stranded DNA）、抗心磷脂IgG（anticardiolipin IgG）及抗心磷脂IgM（anticardiolipin IgM）水平；同时记录所有研究对象的临床症状及基础疾病。
主要及次要结局指标（Primary and secondary outcome measures）：记录血清抗体滴度检测结果；对于血清学检测呈阳性的研究对象，在接受3个月抗结核药物治疗后开展后续复查。
研究结果（Results）：结核患者的抗心磷脂IgG滴度显著高于对照组；将本研究结果与既往人群研究对比后发现，结核患者的抗Scl-70抗体滴度同样显著升高。抗Scl-70阳性患者的后续随访数据显示，经治疗后其抗体滴度有所下降；未观察到血清抗体滴度与临床状况存在相关性。
研究结论（Conclusions）：在结核高流行地区，有32%的结核患者存在自身抗体滴度升高的情况，尤以抗心磷脂IgG及抗Scl-70抗体为著。对于血清自身抗体滴度升高但无典型或多发性自身免疫病表现的患者，应开展分枝杆菌相关检测。
试验注册（Trial registration）：本研究经医院伦理审查委员会批准（NTUH REC: 9561707008），所有患者均已签署知情同意书。