PROJECT SUMMARY/ABSTRACT Candidate: Patricia Vega-Fernandez, MD MSc RhMSUS is a pediatric rheumatologist whose overarching career goal is to improve the outcomes of children affected by autoimmune rheumatologic diseases through a career as an independent clinician scientist focused on biology-based imaging and clinical research to support the development of personalized treatment approaches. Dr. Vega-Fernandez, an Assistant Professor of Pediatrics at Cincinnati Children’s Hospital Medical Center (CCHMC), has conducted multiple studies focused on addressing the feasibility and reliability of musculoskeletal ultrasound (MSUS) in Juvenile Idiopathic Arthritis (JIA). The proposed K23 career development plan will focus on identified gaps in Dr. Vega-Fernandez’s knowledge and training that are essential to advance her career towards an independent investigator: 1) Critical appraisal of the biological signatures in JIA; 2) Performance of US-guided synovial biopsy in children with JIA; 3) Validation of instruments and longitudinal studies; 4) Strengthened personal, academic, and professional skills to become an effective independently funded clinical-scientist. Mentors/Environment: Dr. Vega-Fernandez and her mentors, Hermine Brunner MD MSc MBA, Sherry Thornton PhD, Jonathan Dillman MD MSc, and Jareen Meinzen-Derr PhD MPH, have assembled a strong team of advisors and collaborators from inside and outside of CCHMC to guide the proposed training and research activities. The career development plan utilizes intellectual resources at CCHMC and the University of Cincinnati. Research: JIA, the most common chronic rheumatic disease in childhood, is characterized by joint inflammation (arthritis). Diagnosis of arthritis in children is based on the presence of joint swelling and limited range of motion and/or tenderness on palpation. Given the young age of children at diagnosis, the report of joint pain or limitation of motion can often times be inaccurate. In addition, clinical assessment of active arthritis in the developing skeleton is subjective and has low inter-rater reliability. MSUS can objectively inform presence and severity of joint inflammation. There is a knowledge gap on the clinical significance of MSUS findings in children. The central hypothesis of this study is that a 10-joint focused MSUS score can serve as a diagnostic imaging tool to provide an accurate assessment of both clinical and biologic activity of inflammation over time in children with JIA. Guided by strong preliminary data, this hypothesis will be tested with three specific aims: 1) Determine the convergent validity of the MSUS-10 score across the spectrum of JIA disease activity; 2) Determine the ability of the MSUS- 10 score to capture clinically relevant change of JIA; 3) Evaluate the relationship of the MSUS-10 score with biologic markers of JIA inflammation. The proposed experiments are significant because the MSUS-10 examination and score may support safer and more appropriate ...