Latent tuberculosis screening for inflammatory bowel disease in tuberculosis endemic region remains porous and suboptimal: A multicentre study

Abstract

BACKGROUND

Screening for latent tuberculosis (LTB) before initiating advanced therapy for inflammatory bowel disease (IBD) helps reduce the risk of tuberculosis (TB) development. However, there is limited data on screening practices from TB-endemic regions.

AIM

To study the practices of screening for LTB and study the incidence of TB in patients with IBD on biological and small molecule inhibitors.

METHODS

This retrospective multicentre study analyzed LTB screening practices in IBD patients starting advanced therapies between 2018 and 2022. We included patients who were initiated on biologics (infliximab, adalimumab, vedolizumab) or small molecule inhibitors (tofacitinib). We assessed compliance with LTB screening methods, including the tuberculin skin test, interferon-gamma release assay (IGRA), chest X-ray, and computed tomography chest, both at initiation and annually. We also evaluated the incidence of active TB and its predictors.

RESULTS

Of 378 patients (mean age: 36.9 ± 14.9 years, males: 56.9%), 158 (41.8%) and 216 (57.1%) had ulcerative colitis and Crohn’s disease, respectively. Advanced therapy used were anti-tumor necrosis factor in 309 (81.74%), tofacitinib in 41 (10.84%) and vedolizumab in 28 (7.40%). Standard screening and diligent screening strategy was employed in 59% and 33% of patients, respectively. Compliance with tuberculin skin test and IGRA was noted in 261 (69.04%) and 298 (78.83%) patients, respectively. Chest X-Ray and computed tomography chest were performed in 300 (79.36%) and 242 (64.02%), respectively. Annual screening in those on advanced therapy for > 1 year was performed in 27.2% (50/184). Active TB developed in 17 (4.49%); 15 (88.23%) were on anti-tumor necrosis factor. LTB was detected in 40 (10.72%), with most diagnosed on the basis of IGRA (21/40, 52.50%). Among 17 patients who developed active TB, LTB screen was negative in 12 (70.58%).

CONCLUSION

Standard screening practices for LTB, prior to starting advanced therapy, remain suboptimal (< 60%) in India despite high TB endemicity.

Keywords: Tuberculosis; Inflammatory bowel disease; Advanced therapy; Ulcerative colitis; Crohn’s disease

Core Tip: This multicenter study about inflammatory bowel disease patients on advanced therapy suggests that compliance with standard latent tuberculosis (LTB) screening, as recommended by LTB guidelines, is low at around 60%. Annual screening for LTB was found to be grossly neglected at 27%. Incidence of LTB was 10.7% and active tuberculosis (TB) developed in 4.5% of the patients on advanced therapy. Other interesting finding was occurrence of active TB with any advanced therapy, suggesting that there is no ‘safe’ therapy in TB endemic regions.