Diagnosis of tuberculosis infection in pediatric patients treated with inhibitors of the tumour necrosis factor alpha. A multicenter national study comparing tuberculin skin test and igra tests

Abstract

Introduction: In the last years, inhibitors of tumor necrosis factor alpha (antiTNFa) have been a major advance in the treatment of many rheumatic diseases and inflammatory bowel disease, also in the pediatric patient. However, antiTNFa use is associated with an increased risk of serious infections, including tuberculosis (TB). In adults, the new interferon g release assays (IGRA) tests for the diagnosis of TB infection appear to show better sensitivity and specificity than the tuberculin skin test (TST) in these patients. Data in children are still very scarce. We have previously reported a latent tuberculosis infection (LTI) prevalence rate of 1.4% (95%CI: 0-2.9) in children on antiTNFa treatment, which is similar to that reported in healthy pediatric population studies in Spain. LTI was diagnosed in 3 adolescent girls (out of 221 patients) in whom QTF tested positive, while TST was positive in only one of them. Objectives: To establish the sensitivity and specificity of IGRA tests in the diagnosis of LTI compared to the TST in pediatric patients by the implementation of antiTNFa treatment. Methods: We present an ongoing national multicenter retrospective/ prospective cross-sectional study (hosted by the Spanish National Societies of Pediatric Rheumatology, Infectious Diseases and Gastroenterology) including pediatric patients in whom LTI is to be ruled out simultaneously by TST and IGRA test, prior to initiating treatment with antiTNFa drugs. Medical history related to the underlying disease, the risk of LTI and the results of the TST and IGRA tests will be collected. Conclusion: This study will observe the prevalence of LTI in this cohort, identify risk factors associated with LTI and analyze the sensitivity, specificity and negative predictive value of IGRA tests as compared to TST in children before antiTNFa initiation.