Latent Tuberculosis Infection in Children with Pediatric Rheumatologic Diseases Treated with Canakinumab

Abstract

Objective: Knowledge of the long-term safety of canakinumab (CAN) regarding tuberculosis (TB) in pediatric rheumatologic diseases is limited. To determine the incidence and disease course of latent TB of patients treated with CAN in two centers from Turkiye. Material and Methods: The hospital charts were analysed retrospectively. Tuberculin skin test (TST) and/or QuantiFERON-TB Gold (QFT-G) test were used to screen for TB. Chest X-rays were performed prior to therapy and then yearly. Patients were evaluated for symptoms of active TB. Results: A total of 67 patients were investigated. The median duration of CAN use was three years (ranging from 2-4 years). Nine patients (9/67, 13.4%) had positive TST and one patient (1/11, 1.4%) had positive QFT-G with normal chest X-ray prior to therapy. They were given isoniazid (INH) prophylaxis for latent TB. During follow-up 11 patients (11/56, 19.6%) with TST conversion and two patients (2/22, 9%) with positive QFT-G were given INH prophylaxis. All patients receiving INH prophylaxis had normal chest X-rays and no active TB symptoms. One patient experienced persistent cough and fever at the fourth year of CAN therapy though TST and QFT-G test were negative prior to and during CAN treatment. Chest tomography revealed findings suggestive of pulmonary TB, anti-TB treatment was started. The remaining patients had not developed active TB disease during follow-up. Conclusion: This study suggests that although frequency of latent TB infection in children treated with CAN is not low in a TB endemic country, progression to TB disease under CAN treatment is not a common finding in our study.