AB0933 ANALYSIS OF THE STATE OF IMMUNITY IN PATIENTS WITH JIA IN TREATMENT

Background The correct indication of the suspension of treatment with FAMES and biological therapy in pediatric patients, in the presence of a mild infectious disease or vaccination is a common problem in children’s rheumatology. In patients with juvenile idiopathic arthritis (JIA), joint or extra-articular clinical reactivation during these “pauses” is not uncommon, however, there are not enough studies in the pediatric population to show the influence of treatments on the immune system., and therefore, that justify this clinical practice. Objectives To analyze the levels of T, B and NK lymphocyte subpopulations in patients diagnosed with JIA treated with FAMES and biological therapy. Methods A descriptive and cross-sectional study in which 39 patients from the Pediatric Rheumatology Unit of the Reina Sofia University Hospital were recruited, diagnosed with JIA according to the ILAR 2001 criteria. The patients were divided into four groups: 8 controls in clinical remission without treatment, 17 in treatment with DMARD in monotherapy, 7 in biological treatment in monotherapy and 7 in treatment with DMARD-biological. Patients with systemic JIA were excluded because they had a pathogenic mechanism different from the rest of the JIA categories. By flow cytometry, the levels of CD3, CD4, CD8 and CD19 cells were measured for acquired immunity and from NK for innate, the CD4/CD8 index was also calculated. Results The mean age of the 39 patients was 10 ± 5.7 years, 29 were girls (74.3%), 4 patients had arthritis related to enthesitis, 16 patients had oligoarticular involvement ANA +, 6 subjects polyarticular involvement FR- and 13 they were psoriatic arthritis. Although no statistically significant differences were found when contracting cellular levels among the 4 groups evaluated, it was observed that the group treated with DMARD monotherapy had the highest percentage of children with alterations in cellular levels CD3, CD4, CD8 and CD19 (41.17% of the patients of the group); the group treated in monotherapy with biological treatment (28%) presented alteration in the levels of CD8 and CD19 and the group treated in combination of DMARD and biological (14.28%) in CD19. On the other hand, the NK cells and the CD4/CD8 index were not altered in any of the groups. Only 6 cases of serious infections were registered in patients in combination therapy (DMARD-biologic) who had received corticosteroids by clinical activity. There were no statistical differences between patients who had received corticosteroids and those who did not. Conclusion Patients in treatment with DMARD monotherapy had a tendency to decrease cellular levels. On the other hand, alterations in innate immunity or CD4/CD8 index were not observed. Disclosure of Interests None declared