To investigate the clinical features and potential risk factors of active tuberculosis (ATB) in Behçet’s disease (BD), we conducted a case-control study on hospitalized BD patients in our institute from 2010 to 2019. BD patients with ATB were enrolled as the case group. The control group was selected by random number sampling from the remaining BD patients, including those with latent tuberculosis infection, previous tuberculosis, or without tuberculosis. Finally, we reviewed 386 BD patients and identified 21 (5.4%) ATB cases, including four (19.0%) microbiologically confirmed and 17 (81.0%) clinically diagnosed. We found that BD patients with ATB were more prone to have systemic symptoms (fever, night sweating, and unexplained weight loss) and/or symptoms related to the infection site. Multivariate logistic regression analysis revealed that erythrocyte   sedimentation   rate   ESR > 60  mm/h ( OR = 13.710 , 95% CI (1.101, 170.702)), increased IgG ( OR = 1.226 , 95% CI (1.001, 1.502)), and positive T-SPOT.TB ( OR = 7.793 , 95% CI (1.312, 48.464), for 24-200 SFC/106PBMC; OR = 17.705 95% CI (2.503, 125.260), for >200 SFC/106PBMC) were potential risk factors for ATB in BD patients. Our study suggested that when BD patients have systemic symptoms with significantly elevated TB-SPOT, the diagnosis of ATB should be considered.

Background Understanding the clinical characteristics and risk factors of active tuberculosis (ATB) in Behçet’s disease (BD) is of great significance to improve the treatment efficacy and guide the preventive treatment. However, the relevant studies are very limited. Methods We retrospectively reviewed medical records of BD patients admitted to our institute from 2010 to 2019. BD patients with ATB were enrolled as the case group, and the control group was selected by random number sampling from the remaining BD patients. Multivariate logistic regression analysis was performed to explore the potential risk factors of ATB in BD patients. Figure 1. Flowchart of the study Results Twenty-one ATB cases were identified from 386 BD patients, including four (19.0%) microbiologically confirmed and 17 (81.0%) clinically diagnosed. ATB patients can present with systemic symptoms (fever, night sweating, unexplained weight loss) and/or symptoms related to the infection site. Logistic regression analysis revealed that ESR>60mm/h (OR=13.710, 95%CI (1.101, 170.702)), increased IgG (OR=1.226, 95%CI (1.001, 1.502)), and positive T-SPOT.TB (OR=7.793, 95%CI (1.312, 48.464), for 24-200 SFC/106PBMC; OR=17.705 (2.503, 125.260), for >200 SFC/106PBMC) were potential risk factors for ATB in BD patients. Table 1. Past medical history and medication of BD patients with and without ATB Table 2. Clinical presentation and laboratory results of BD patients with and without ATB Table 3. Potential risk factors for ATB in BD patients Conclusion When BD patients have fever, night sweating, unexplained weight loss, or manifestations rarely occurred in BD, the diagnosis of ATB should be considered. Significantly elevated T-SPOT.TB indicates a high risk of ATB in BD patients. Disclosures All Authors: No reported disclosures