Systemic vasculitis with latent tuberculosis infection and associated factors: a cross-sectional multicenter study.

OBJECTIVES

Systemic vasculitis patients are at a higher risk of developing latent tuberculosis infection (LTBI). However, there is currently no literature elucidating the positivity rate and risk factors for LTBI in systemic vasculitis patients.

METHODS

Our study is a multi-center, cross-sectional study that enrolled systemic vasculitis patients from 13 comprehensive hospitals in China. T-SPOT.TB as the screening method for LTBI, the study investigated the positivity rate of LTBI in systemic vasculitis patients and the factors associated with T-SPOT.TB results.

RESULTS

A total of 191 systemic vasculitis patients were included and the positive rate of T-SPOT.TB was 31.4%. The highest T-SPOT.TB positivity rate was observed in Behçet's syndrome (BD) (72/191, 37.7%). There were statistically significant differences between the LTBI group and non-LTBI group in terms of systemic vasculitis type (P = 0.010), albumin levels (P = 0.034), erythrocyte sedimentation rate (P = 0.016), and corticosteroid dosage (P = 0.047). Multivariate regression analysis revealed that smoking history (aOR = 3.809, 95%CI: 1.341-10.817) and BD (aOR = 2.106, 95%CI: 1.042-4.254) were independent risk factors of T-SPOT.TB postive results, besides decreased lymphocyte count (aOR = 0.114, 95%CI: 0.013-0.973), and high-dose glucocorticoids use (aOR = 0.386, 95%CI: 0.149-1.003) were independent risk factors of T-SPOT.TB negative results.

CONCLUSIONS

The prevalence of LTBI is high in systemic vasculitis patients, especially those with BD or smoking history. Patients with decreased lymphocyte counts and high-dose glucocorticoid use are more likely to have a negative T-SPOT.TB results. Therefore, LTBI screening should be performed based on the characteristics of the patient during the diagnosis and treatment of systemic vasculitis. Key Points • We explored the positivity rate and risk factors of LTBI in systemic vasculitis patients from 13 hospitals in China. • There were 191 systemic vasculitis patients in our study. The positive rate of T-SPOT.TB was 31.4%. The predominant type of systemic vasculitis was BD, with a T-SPOT.TB positive rate of 44.4%. The second type was TA, with a T-SPOT.TB positive rate of 25.0%. • The prevalence of LTBI is high in systemic vasculitis patients, especially those with Behçet's syndrome or smoking history. Decreased lymphocyte counts and high-dose glucocorticoid use are more likely to have a negative T-SPOT.TB results. • LTBI screening using T-SPOT.TB should be conducted during the diagnosis and treatment of systemic vasculitis.