Utilization of Whole-Body Magnetic Resonance Imaging in Challenging Diagnoses in Pediatric Rheumatology.

The aim of this study was to investigate the use of whole-body magnetic resonance imaging (WBMRI) in cases where we suspected rheumatic disease in our pediatric rheumatology clinic. We conducted a retrospective analysis of demographic, clinical, laboratory, and imaging data pertaining to pediatric patients who presented at our clinic and underwent WBMRI over the last 5 years. Our investigation targeted children experiencing diffuse musculoskeletal pain, where precise localization was challenging and suspicion of rheumatological pathology persisted despite inconclusive results from conventional diagnostic modalities. A total of 87 patients (33 female) underwent WBMRI at our clinic, with a median age (minimum-maximum) of 11.3 (0.5-18) years. Whole-body magnetic resonance imaging was performed in 4 patients suspected with dermatomyositis (DM) where muscle biopsy was not feasible, revealing muscle involvement and myositis. Additionally, WBMRI was utilized in 4 patients diagnosed with chronic nonbacterial osteomyelitis (CNO) to assess recurrence, identifying new active lesions in 3 patients. Among the remaining 79 patients, 34 received a new diagnosis of CNO. Clinically, supported by additional findings in laboratory and WBMRI, 18 were diagnosed with juvenile idiopathic arthritis (JIA), 5 with protracted febrile myalgia syndrome (PFMS), 5 with acute osteomyelitis, and 1 with viral myositis. The results were normal for 17 patients. Most of the WBMRIs conducted at the clinic under study were primarily performed on patients suspected of having CNO. Additionally, WBMRI was found to be supportive and beneficial in cases of suspected DM, PFMS, and JIA during the diagnosis.