Serum S100A8/A9 and S100A12 Levels in Children With Polyarticular Forms of Juvenile Idiopathic Arthritis: Relationship to Maintenance of Clinically Inactive Disease During Anti-Tumor Necrosis Factor Therapy and Occurrence of Disease Flare After Discontinuation of Therapy.

OBJECTIVE: To determine the relationship between serum levels of S100A8/A9 and S100A12 and the maintenance of clinically inactive disease during anti-tumor necrosis factor (anti-TNF) therapy and the occurrence of disease flare following withdrawal of anti-TNF therapy in patients with polyarticular forms of juvenile idiopathic arthritis (JIA). METHODS: In this prospective, multicenter study, 137 patients with polyarticular-course JIA whose disease was clinically inactive while receiving anti-TNF therapy were enrolled. Patients were observed for an initial 6-month phase during which anti-TNF treatment was continued. For those patients who maintained clinically inactive disease over the 6 months, anti-TNF was withdrawn and they were followed up for 8 months to assess for the occurrence of flare. Serum S100 levels were measured at baseline and at the time of anti-TNF withdrawal. Spearman's rank correlation test, Mann-Whitney U test, Kruskal-Wallis test, receiver operating characteristic (ROC) curve, and Kaplan-Meier survival analyses were used to assess the relationship between serum S100 levels and maintenance of clinically inactive disease and occurrence of disease flare after anti-TNF withdrawal. RESULTS: Over the 6-month initial phase with anti-TNF therapy, the disease state reverted from clinically inactive to clinically active in 24 (18%) of the 130 evaluable patients with polyarticular-course JIA; following anti-TNF withdrawal, 39 (37%) of the 106 evaluable patients experienced a flare. Serum levels of S100A8/A9 and S100A12 were elevated in up to 45% of patients. Results of the ROC analysis revealed that serum S100 levels did not predict maintenance of clinically inactive disease during anti-TNF therapy nor did they predict disease flare after treatment withdrawal. Elevated levels of S100A8/A9 were not predictive of the occurrence of a disease flare within 30 days, 60 days, 90 days, or 8 months following anti-TNF withdrawal, and elevated S100A12 levels had a modest predictive ability for determining the risk of flare within 30, 60, and 90 days after treatment withdrawal. Serum S100A12 levels at the time of anti-TNF withdrawal were inversely correlated with the time to disease flare (r = -0.36). CONCLUSION: Serum S100 levels did not predict maintenance of clinically inactive disease or occurrence of disease flare in patients with polyarticular-course JIA, and S100A12 levels were only moderately, and inversely, correlated with the time to disease flare.

Risk, Timing, and Predictors of Disease Flare After Discontinuation of Anti-Tumor Necrosis Factor Therapy in Children With Polyarticular Forms of Juvenile Idiopathic Arthritis With Clinically Inactive Disease.

OBJECTIVE: To determine the frequency, time to flare, and predictors of disease flare upon withdrawal of anti-tumor necrosis factor (anti-TNF) therapy in children with polyarticular forms of juvenile idiopathic arthritis (JIA) who demonstrated ≥6 months of continuous clinically inactive disease. METHODS: In 16 centers 137 patients with clinically inactive JIA who were receiving anti-TNF therapy (42% of whom were also receiving methotrexate [MTX]) were prospectively followed up. If the disease remained clinically inactive for the initial 6 months of the study, anti-TNF was stopped and patients were assessed for flare at 1, 2, 3, 4, 6, and 8 months. Life-table analysis, t-tests, chi-square test, and Cox regression analysis were used to identify independent variables that could significantly predict flare by 8 months or time to flare. RESULTS: Of 137 patients, 106 (77%) maintained clinically inactive disease while receiving anti-TNF therapy for the initial 6 months and were included in the phase of the study in which anti-TNF therapy was stopped. Stopping anti-TNF resulted in disease flare in 39 (37%) of 106 patients by 8 months. The mean/median ± SEM time to flare was 212/250 ± 9.77 days. Patients with shorter disease duration at enrollment, older age at onset and diagnosis, shorter disease duration prior to experiencing clinically inactive disease, and shorter time from onset of clinically inactive disease to enrollment were found to have significantly lower hazard ratios for likelihood of flare by 8 months (P < 0.05). CONCLUSION: Over one-third of patients with polyarticular JIA with sustained clinically inactive disease will experience a flare by 8 months after discontinuation of anti-TNF therapy. Several predictors of lower likelihood of flare were identified.

High Levels of DEK Autoantibodies in Sera of Patients With Polyarticular Juvenile Idiopathic Arthritis and With Early Disease Flares Following Cessation of Anti-Tumor Necrosis Factor Therapy.

OBJECTIVE: The nuclear oncoprotein DEK is an autoantigen associated with juvenile idiopathic arthritis (JIA), especially the oligoarticular subtype. DEK is a secreted chemotactic factor. Abundant levels of DEK and DEK autoantibodies are found in inflamed synovium in JIA. We undertook this study to further characterize the nature of DEK autoantibodies in screening serum samples from 2 different cohorts that consisted mostly of patients with JIA. METHODS: DEK autoantibody levels were analyzed in sera from 33 JIA patients, 13 patients with other inflammatory conditions, and 11 healthy controls, as well as in 89 serum samples from JIA patients receiving anti-tumor necrosis factor (anti-TNF) therapy. Recombinant His-tagged full-length DEK protein (1-375 amino acids [aa]) and the 187-375-aa and 1-350-aa His-tagged DEK fragments made in a baculovirus system were used for enzyme-linked immunosorbent assay (ELISA) and immunoblotting. The C-terminal 25-aa fragment of DEK was expressed in a glutathione S-transferase-tagged vector. ELISA results were calculated as area under the curve by the trapezoidal rule. RESULTS: DEK autoantibody levels were significantly higher in patients with polyarticular JIA than in those with oligoarticular JIA, and were higher in patients with polyarticular JIA who had more active disease after cessation of anti-TNF therapy. Immunoblotting against the C-terminal 25-aa fragment of DEK confirmed that this section of the DEK molecule is the most immunogenic domain. CONCLUSION: DEK autoantibody levels are higher in patients with polyarticular JIA than in those with oligoarticular JIA, and higher in patients who have disease flares after cessation of anti-TNF therapy. The C-terminal 25-aa fragment is the most immunogenic portion of DEK. These findings are significant with respect to the nature of DEK autoantibodies, their contribution to JIA pathogenesis, and their implications for JIA management.

Chronic granulomatous disease presenting as aseptic ascites in a 2-year-old child.

Chronic granulomatous disease (CGD) is a rare inherited immunodeficiency syndrome that results from abnormal nicotinamide adenine dinucleotide phosphate (NADPH) oxidase function. This defect leads to recurrent catalase-positive bacterial and fungal infections as well as associated granuloma formation. We review the case of a 2-year-old boy who presented with ascites and fever of an unknown origin as manifestations of CGD. Cultures were negative for infection throughout his course, and CGD was suspected after identification of granulomas on peritoneal biopsy. Genetic testing revealed a novel mutation in the CYBB gene underlying his condition. This paper highlights the importance of considering CGD in the differential diagnosis of fever of unknown origin and ascites in children.