Incidence, risk factors for active tuberculosis infection and changes of IGRA in patients with Takayasu arteritis: a prospective cohort study

There is limited evidence to support the association between tuberculosis (TB) and the occurrence of Takayasu arteritis (TAK). To investigate the incidence of active TB (ATB) in TAK and explore the impact of anti-rheumatic therapy on the occurrence of ATB or reactivation of Latent TB infection (LTBI) and their effect on interferon-γ release assay (IGRA) results, we conducted a prospective study based on the Chinese Registry for Systemic Vasculitis cohort. The standard incidence ratio (SIR) was calculated and stratified by age. Kaplan–Meier analysis was used to determine the effect of variables on ATB or LTBI reactivation in patients with TAK. Data from 825 patients with TAK in the registry were analysed. During a median follow-up of 5 years, 5 patients developed ATB with a crude incidence of 154 (95%CI:57–381) person-years/100,000. The SIR was 5.59 (95%CI:1.81–13.04). Glucocorticoids and conventional disease-modifying anti-rheumatic drugs (cDMARDs) did not increase the risk of ATB or LTBI reactivation (<i>P</i> &gt; 0.05). However, the use of tumour necrosis factor inhibitor (TNFi) increased the risk of ATB in patients with LTBI (<i>P</i> &lt; 0.001). Furthermore, the value of the IGRA assay decreased after treatment (<i>P</i> &lt; 0.05). In conclusion, the incidence of TB infection is markedly increased in patients with TAK and patients with TAK are at high risk of developing ATB. Treatment with glucocorticoids and cDMARDs does not significantly increase the risk for ATB in patients with TAK. Moreover, IGRA may have limited effectiveness in monitoring ATB infection or LTBI reactivation in patients with TAK.

目前关于结核病（tuberculosis, TB）与高安动脉炎（Takayasu arteritis, TAK）之间的关联证据较为有限。为探究高安动脉炎患者的活动性结核病（active TB, ATB）发生率，探讨抗风湿治疗对活动性结核病发生或潜伏性结核感染（Latent TB infection, LTBI）复燃的影响，及其对γ干扰素释放试验（interferon-γ release assay, IGRA）结果的作用，本研究基于中国系统性血管炎登记队列开展了一项前瞻性研究。本研究计算了标准化发病率（standard incidence ratio, SIR）并按年龄分层，采用Kaplan-Meier分析评估各变量对高安动脉炎患者发生活动性结核病或潜伏性结核感染复燃的影响。本研究共纳入登记队列中825例高安动脉炎患者进行分析。在中位随访5年期间，共有5例患者罹患活动性结核病，粗发病率为154（95%置信区间：57~381）人年/10万，标准化发病率为5.59（95%置信区间：1.81~13.04）。糖皮质激素与传统改善病情抗风湿药（conventional disease-modifying anti-rheumatic drugs, cDMARDs）并未增加活动性结核病或潜伏性结核感染复燃的风险（P>0.05）。然而，肿瘤坏死因子抑制剂（tumour necrosis factor inhibitor, TNFi）的使用会升高潜伏性结核感染患者罹患活动性结核病的风险（P<0.001）。此外，γ干扰素释放试验的检测值在治疗后出现显著下降（P<0.05）。综上，高安动脉炎患者的结核感染发生率显著升高，且罹患活动性结核病的风险较高。糖皮质激素与传统改善病情抗风湿药治疗并不会显著升高高安动脉炎患者的活动性结核病风险。此外，γ干扰素释放试验在监测高安动脉炎患者的活动性结核病感染或潜伏性结核感染复燃方面的有效性较为有限。