Juvenile idiopathic arthritis (JIA) is an exclusion diagnosis that encompasses all forms of otherwise unexplained chronic non-infectious arthritis occurring under the age of 16. Various attempts have been made to classify this heterogeneous group of diseases with the aim of identifying mutually exclusive categories suitable for etiopathogenetic studies. Since then increasing evidence has accumulated suggesting that some of these categories are heterogeneous. Therefore, there is a need to revise the criteria in order to identify more homogeneous entities and to try to distinguish those diseases. The main reason for this research study is to learn more about the diagnosis of Juvenile Idiopathic Arthritis (JIA) according to the ILAR (International League of Associations for Rheumatology) criteria and investigate a new classification criteria proposed by the international research organization Paediatric Rheumatology International Trials Organisation (PRINTO) and the Pediatric Rheumatology Collaborative Study Group (PRCSG).
- A diagnosis of JIA according to the ILAR criteria by the treating physician.
- The availability to provide an evaluation within 6 months after the onset of JIA. The onset evaluation can also be completed retrospectively (based on reliable family history or prior attending physician’s reports), but only if joint assessment data can be provided.
- A clinical evaluation 3 months apart and then at least annually up to year 5.
- The availability to centrifuge and collect samples
The project includes the enrollment of a prospective cohort of at least 1,000 JIA patients, evaluated at onset and at 4 times points since the disease onset (within the first and after at least 3 months the second and then at least annually up to year 5. Related biologic samples will be collected at the first 2 time points (ANA, anti CCP, RF, HLA B27). The left over of the HLA B27 samples will be used for additional genetic analysis providing the family/patient consent/assent and additional approval by the ethics committee. Ideally 2 EDTA tubes (2 mL each if allowed by the weight of the child) Ideally 2 serum tube (4 mL each if allowed by the weight of the child). The total amount of blood will be according to EU international guidelines. Below are routine clinical care assessments that will be used as research measures in this study:
- Physical examination, including measurement of weight, height, blood pressure, pulse rate and temperature.
- Medical history (including if subject has received intra-articular injections), past and present medications
- Joint examination to measure if the arthritis is causing changes ini the joints. Joint infection assessment
- Tender entheseal assessment.
- Assessment of related JIA conditions: Dactilitis, psoriasis and uveitis.
- Questions related to arthritis symptoms such as how much pain subject is feeling and the ability to function
- Subject medical history
- Subject’s family history of select autoimmune diseases
- Ultrasound assessment (only performed in selected centres)