Tuberculosis screening before biologic therapy: considering epidemiology

We read with interest the retrospective evaluation by Tan et al., entitled ‘Are chest X-rays still necessary for prebiologic tuberculosis screening? A retrospective audit’ recently published in Clinical and Experimental Dermatology. The authors report that including interferon-γ release assay-based screening may be sufficient in a dermatology cohort and that the additional diagnostic contribution of routine chest X-ray remains limited. However, as the study was conducted in a population with a low incidence of tuberculosis, the generalizability of the findings to different epidemiological contexts warrants careful consideration.