Recommendations for tuberculosis screening before and during treatment with tumour necrosis factor inhibitors

Patients with an autoimmune disease, such as rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, Crohn's disease, ulcerative colitis, uveitis or psoriasis, and treated with the anti-tumour necrosis factor (TNF) alpha inhibitors are at high risk of developing various infections including tuberculosis (TB). Serious infections are the result of the patients' immunocompromised status that is caused by the primary disease itself, as well as by previous immunosuppressive therapy. In order to decrease the risk of developing TB, prior to the introduction of the anti-TNF alpha therapy, all patients should undergo screening for TB. Experiences from the countries that have already implemented recommendations for TB screening show a significant decrease in TB occurrence in the anti-TNF alpha treated patients. The PPD skin test result is considered positive if induration is of size ?5 mm. The BCG vaccine applied at birth has no effect on interpretation of PPD test results in adults. The diagnosis of active TB is contraindicated for the introduction of the anti-TNF alpha therapy; first, such patients should receive the TB treatment; and 6 months after the completion of the TB treatment, the introduction of the anti-TNF alpha therapy may be considered. The patients with the diagnosis of the latent TB infection (LTBI) should not immediately start with the anti-TNF alpha therapy, but they should first receive the TB chemoprophylaxis; not earlier than a month upon the introduction of the TB chemoprophylaxis, the anti-TNF alpha therapy may be introduced. The first TB follow-up screening during the anti-TNF alpha therapy is recommended 6 months after the anti-TNF alpha therapy has been introduced and the next one should be scheduled after 12 months.