Clinical assessment in juvenile idiopathic inflammatory myopathies and the development of disease activity and damage tools.

PURPOSE OF REVIEW: In the past few years, adult and pediatric experts in the field have combined their skills to achieve major advances in clinical research on pediatric inflammatory myopathies. As rare diseases, it has become recognized that international trials are needed to assess drug treatments and their long-term sequelae. Tools for assessing specific aspects of disease are available and have been studied to better understand their performance strengths and limitations. These tools have been incorporated into disease activity and damage scores that have been developed by international consensus and are now being evaluated.

RECENT FINDINGS: This review focuses on the tools whose evaluations have been published in the past year and includes methods to assess muscle strength and function in children with myositis. Two international collaborative efforts have focused on disease activity and damage assessments, and their findings are discussed. Some papers highlighting further diagnostic investigations are also reviewed.

SUMMARY: The standardization of assessment tools has enormous implications for future clinical practice: (1) Clinicians who are not experienced in these rare disorders will be able to evaluate their patients appropriately and highlight important clinical signs that are of prognostic importance. (2) International drug trials can be undertaken and thus improve our understanding of the impact of medication on the disease process. (3) Follow-up studies can be undertaken with sufficient numbers of patients to answer questions about the long-term sequelae of the disease and its treatments.