Risk of tuberculosis in pediatric patients treated with biological agents

Objectives: Biological agents are frequently used in inflammatory diseases in childhood. We aim to determine the incidence of latent tuberculosis infection (LTBI) and tuberculosis disease (TB) during follow-up due to use of biological agents. Methods: Between 2008-2019, all 194 patients who were followed up in pediatric pulmonology department in terms of LTBI and TB disease occurance while using biological agents were included in the study. Tuberculin skin test (TST), interferon gamma release assay (IGRA) tests and lung imaging (chest X-ray and/or tomography) before and during the treatment with biological agents were evaluated. Results: The mean duration of biological agent treatment was 35.5±25.6 months and 156 (80.4%) patients had rheumatological diseases. In the pretreatment evaluation 26 (13.4%) patients had positive TST and all these patients were given isoniazid (INH) prophylaxis after excluding TB disease. During follow-up, TST of 5 (2.6%) patients became positive and they received INH prophylaxis. TB disease was occured in follow up of one of the TST-negative patients. IGRA became positive in the second year of biological agent, sputum culture grew M. tuberculosis and the chest CT showed tree-in-bud pattern consistent with pulmonary tuberculosis. Conclusions: There is a risk of LTBI and TB disease under biological agent treatment in children. Care should be taken that TB can be seen during treatment even in patients who did not have LTBI in pretreatment evaluation of biological agents and patients should be controlled frequently in terms of developing LTBI and TB disease.