Clinical features, treatment and outcomes of Italian children with enthesitis-related arthritis and juvenile psoriatic arthritis: a cross-sectional cohort study

Objective Limited information is available on the clinical features, treatment modalities and outcomes of the juvenile idiopathic arthritis (JIA) categories of enthesitis-related arthritis (ERA) and juvenile psoriatic arthritis (JPsA). This study was aimed to describe the characteristics of Italian children with ERA and JPsA and to compare them with those of patients with the other categories of JIA. Methods Patients were part of a multinational sample included in a study aimed to investigate the prevalence of disease categories, treatment approaches, and disease status in patients from across different geographical areas (EPOCA Study). All patients underwent a retrospective assessment, based on the review of clinical chart, and a cross-sectional evaluation, which included assessment of physician- and parent-reported outcomes and laboratory tests, and recording of ongoing therapies. Results Of the 9081 children with JIA enrolled in the EPOCA Study, 1300 were recruited at 18 paediatric rheumatology centres in Italy. 45 (3.5%) had ERA and 49 (3.8%) had JPsA. Several remarkable differences in demographic features and frequency of articular and extra-articular manifestations, disease damage, impairment in physical function and health-related quality of life, school-related problems, comorbidities, and ongoing treatments were observed between ERA and JPsA and the other JIA categories. Conclusion We described the characteristics of Italian children with ERA and JPsA and highlighted their peculiarities and their differences from the other JIA subsets. These data provide useful insights for future revisions of JIA classification and a benchmarking against which the features from other cohorts may be compared.