Performance of a pediatric adaptation of the RITE and APE2 scores in children with autoimmune epilepsy: P-RITE and P-APE scores.

INTRODUCTION

In adult patients with epilepsy, predictive models have been developed and validated for anticipating a favorable response to immunotherapy. However, no such model has been evaluated in children.

METHODS

This retrospective cohort study intended to assess the performance of a pediatric adaptation of the Response to Immunotherapy in Epilepsy (RITE) score: P-RITE score and Antibody Prevalence in Epilepsy (APE) score: P-APE score in patients aged 1-18 years. We included data of those patients who had epilepsy duration of not more than 12 months, no other known etiology (e.g., genetic, metabolic, neoplastic, or structural causes), and tested for neural-specific antibody in cerebrospinal fluid or serum for P-APE score and only those who received immunotherapy for P-RITE score. We added cognitive dysfunction, speech dysfunction, sleep disturbance, and movement disorder to the original scores to increase specificity for pediatric autoimmune epilepsy. We assumed at least a 50% reduction in seizure frequency at 6 months as a favorable response to immunotherapy. Cut-offs were chosen for both scores to maximize true positives and minimize false negatives using ROC curves.

RESULTS

We included data from a total of 237 patients with epilepsy (10.4 ± 2.5 years, 129 boys, 54%), out of which, 25 (10.5%, 13 girls, 52%) tested positive for autoantibodies. The median P-APE score in the subgroup with and without antibody positivity were 7 (IQR: 5-11) and 2 (IQR: 1-5), respectively (p<0.0001). ROC analysis of the P-APE score determined an AUC of 0.96. The sensitivity and specificity values of the P-APE score ≥6 were 94% and 92%, respectively. A total of 162 patients (10.3 ± 2.5 years, 88 boys, 54%) received immunotherapy, out of which, 101 had a favorable response at 6 months. The median P-RITE score in the subgroup with and without favorable response following a trial of immunotherapy were 10 (IQR: 6-17) and 3 (IQR: 1-6), respectively (p<0.0001). ROC analysis of the P-RITE score determined an AUC of 0.96. The sensitivity and specificity values of P-RITE score ≥8 were 95% and 93%, respectively. The AUC of both these ROCs was significantly higher than the AUC of ROCs for original scores in our cohort.

CONCLUSION

The P-RITE and P-APE scores can be used to predict the response to immunotherapy and predict autoantibody positivity in children with epilepsy with/without encephalopathy or cognitive dysfunction.