RELIABILITY OF ELISA TEST IN THERAPEUTIC DRUG MONITORING OF ADALIMUMAB AND INFLIXIMAB IN PEDIATRIC INFLAMMATORY BOWEL DISEASE

<p style="text-align: justify;">Inflammatory bowel disease (IBD) is a significant cause of morbidity and disability in pediatric patients, characterized by chronic intestinal inflammation. Biologic therapies, such as adalimumab and infliximab, are widely used for induction and maintenance of remission. Therapeutic drug monitoring (TDM) enables individualized treatment by optimizing drug dosage based on serum concentrations. The aim was to evaluate the reliability of the enzyme-linked immunosorbent assay (ELISA) for determining serum levels of adalimumab and infliximab in pediatric patients with IBD. This retrospective study analyzed serum samples from 40 pediatric patients, divided into two groups: 20 receiving adalimumab or infliximab therapy and 20 controls. Serum levels were measured using the RIDASCREEN ELISA kits (R-Biopharm AG) and Dynex DS2 analyzer. Method reliability was assessed through precision, accuracy, sensitivity, and specificity.Calibration curves demonstrated high reliability, with coefficients of determination (R²) of 0.998 (adalimumab) and 0.999 (infliximab). Precision, indicated by coefficients of variation, was 4.3% for adalimumab and 4.1% for infliximab. Accuracy, measured by bias, was 3.75% for adalimumab and 0.05% for infliximab. Sensitivity and specificity were both 100%, confirming the test's ability to accurately detect or exclude drug presence in serum samples. R-Biopharm AG ELISA-based TDM provides reliable, precise, and accurate results for monitoring adalimumab and infliximab levels in pediatric patients. These findings support its use as a gold standard for individualized treatment optimization in IBD.</p>