American College of Rheumatology Provisional Criteria for Clinically Relevant Improvement in Children and Adolescents With Childhood‐Onset Systemic Lupus Erythematosus

Abstract

Objective To develop a Childhood Lupus Improvement Index ( CHILI ) as a tool to measure response to therapy in childhood‐onset systemic lupus erythematosus ( cSLE ), with a focus on clinically relevant improvement ( CRI c SLE ). Methods Pediatric nephrology and rheumatology subspecialists (n = 213) experienced in cSLE management were invited to define CRI c SLE and rate a total of 433 unique patient profiles for the presence/absence of CRI c SLE . Patient profiles included the following cSLE core response variables ( CRV s): global assessment of patient well‐being (patient‐global), physician assessment of cSLE activity ( MD ‐global), disease activity index score (here, we used the Systemic Lupus Erythematosus Disease Activity Index), urine protein‐to‐creatinine ratio, and Child Health Questionnaire physical summary score. Percentage and absolute changes in these cSLE ‐ CRV s (baseline versus follow‐up) were considered in order to develop candidate algorithms and validate their performance (sensitivity, specificity, area under the receiver operating characteristic curve [ AUC ]; range 0–1). Results During an international consensus conference, unanimous agreement on a definition of CRI c SLE was achieved; cSLE experts (n = 13) concurred (100%) that the preferred CHILI algorithm considers absolute changes in the cSLE ‐ CRV s. After transformation to a range of 0–100, a CHILI score of ≥54 had outstanding accuracy for identifying CRI c SLE ( AUC 0.93, sensitivity 81.1%, and specificity 84.2%). CHILI scores also reflect minor, moderate, and major improvement for values exceeding 15, 68, and 92, respectively (all AUC ≥0.92, sensitivity ≥93.1%, and specificity ≥73.4%). Conclusion The CHILI is a new, seemingly highly accurate index for measuring CRI in cSLE over time. This index is useful to categorize the degree of response to therapy in children and adolescents with cSLE .