DIAGNOSTICS OF LATENT TUBERCULOSIS (TB) IN ADULT VACCINATED PATIENTS (BCG) IN CROATIA BEFORE INTRODUCTION OF TUMOR NECROSIS FACTOR ANTAGONIST THERAPY
Authors:
Sanja Popović-Grle, Đurđica Babić-Naglić
Summary
Tuberculosis is now well known adverse event during anti-TNFα therapy and screening for TB is highly recommended before the administration of anti-TNF blockers. The purpose of screening is to asses the risk of reactivation of latent TB or new infection with mycobacterium tuberculosis. Skin test for TB with induration of 5 mm and more is considered positive. Negative skin test in immunocompromised persons does not exclude latent inefction and booster testing after 7 days is suggested. All patients with any suspicious or unclear skin testing (PPD > 5 mm on initial or booster testing) need immunologic diagnostic approach. Patients with confirmed risk for TB must take chemoprofi laxis for 6 months (isoniasid 5 mg per kilogram of body weight). Anti-TNF therapy could be started after 2 months of chemotherapy. All 3 anti-TNF biologics have the same risk of new TB infection and it seems that monoclonal antibodies have some higher risk for reactivation of latent TB. Anyhow for all biologics the same pre-therapy screening procedure is strongly recommended.