Objectives: Extra-osseous (EO) manifestations are poorly characterized in chronic recurrent multifocal osteomyelitis (CRMO). This study aimed to further define the frequency, characteristics and treatment of EO events in CRMO and whether different phenotypes can be distinguished and benefit from special management.
Methods: This multicentre retrospective study included CRMO patients followed in several paediatric rheumatology departments in France between 2015 and 2022.