Ab1417 how to diagnose: juvenile psoriatic arthritis. multicenter prospective observational study in children with suspected diagnosis

Background Juvenile psoriatic artritis (JPSA), a subtype of juvenile idiopathic arthritis (JIA), constitutes 5% of JIA. The literature is inconsistent regarding features of JPSA, and physicians debate whether it is a distinct entity within JA. Moreover, the criteria diagnosis for JPsA is currently in debate.There are two pediatric diagnostic classifications based on clinical criteria: ILAR classification criteria and Vancouver classification criteria. Classification of JIA has been a great debate since this entity disappeared. [1] The CASPAR criteria are standard in adults. These criteria have a specificity of 91.4% and a sensitivity of 98.7%, makingdiagnostic classification easier. However, the peculiarities of childhood cause some differences to consider. Objectives To compare 3 diagnostic criteria for JPSA ILAR, Vancouver and CASPAR. Methods Multicenter, cross-sectional study of data from children with JPsA (diagnosis by prescritor physician) who consecutivelly attended in ped-rheumatology outpatient clinic and enrolled from 9 centers within the last 1.5 years. Sociodemographic, clinical characteristics and family history of Psoriasis were collected to assess compliance with diagnostic classification criteria using using the Cohen’s Kappa statistic index. Results Forty eight children were included with the following sociodemographics characteristics;(table1) Thirty eight children who met the VANCOUVER criteria (80,9%) while thirty two children met the ILAR criteria (68.1%). As for the CASPAR criteria, thirty eight children were diagnosed (80.9%). The diagnostic agreement between the ILAR and CASPAR criteria and ILAR and Vancouver criteria (diagnosed defined) was weak (K=0.67 and K=0.67). In contrast, the agreement was total (K=1 between the CASPAR and Vancouver criteria. Conclusion Despite minimal changes between the Vancouver and ILAR criteria, the ILAR exclusion criteria limit the diagnosis of PsA in childhood. Given that the CASPAR and Vancouver were able to detect a significant number of patients with PsA in our series (predominantly adolescents), the application of the CASPAR criteria in the subgroup of children with late onset could be considered. References [1] Alberto martini, Angelo Ravelli, Tad Avcin, et al. Toward new Classification Criteria for Juvenile Idiopathic Arthritis: First Steps, Pediatric Rheumatology International Trials Organization International Consensus; J Rheumatol. 2019: 46(2):190-197. Table 1. Clinical and demographic data of the study population Total (n=48) Sex, female (% ) 34(70.8) Age at inclusion (years), mean (SD) 11.5(4) Age at articular onset (years), mean (SD) 7.1(5) Age at psoriasis onset (years), mean (SD) 10(3.2) Type of onset Oligoarthritis n (%) 33(68.7) Poliarthritis n (%) 12(25) No arthritis n (%) 3(6.2) Family with Psoriasis 39(81.2) Extra-articular involvement Uveitis n (%) (12.5) Entesitis n (%) 7(14.6) Onicopathy n(%) 14(29.2) ---.Skin-Psoriasis 26(54.2) Lab AAN: positive n (%) 19(39.5) RF: negative n (%) 48(100) HLAB27: negative n (%): 43(89.6) Acknowledgements: NIL. Disclosure of Interests Natalia Palmou-Fontana: None declared, Inmaculada Calvo Speakers bureau: ABVIEE, NOVARTIS, JANSEN, GSK, GISELLA DIAZ CORDOVES REGO: None declared, ADRIAN GARCIA-ROGERO: None declared, Juan Carlos Lopez Robledillo: None declared, Berta Paula Magallares López: None declared, Pablo Mesa del Castillo: None declared, ESTEFANIA MORENO RUZAFA: None declared, CARLOS REDONDO-FIGUERO: None declared, MARTINA STEINER: None declared, PAZ COLLADO: None declared.