Persistent neuroinflammation of the right insular cortex in children with juvenile idiopathic arthritis: a proton MRS study.

OBJECTIVE: The aim of this study of children with juvenile idiopathic arthritis (JIA) was to use proton magnetic resonance spectroscopy (1H-MRS) to compare the levels of five neurometabolites in the right and left insular cortexes of subjects in three groups: JIA-active, JIA-inactive, and healthy controls (HCs). METHODS: Two inflammation markers and five psychometric scores were determined. 1H-MRS was used to measure the levels of total N-acetylaspartate (NAA), total choline (Cho), myo-inositol (mI), and glutamate (Glu), and the complex of glutamine and glutamate (Glx) relative to total creatine (tCr) in the right and left insular cortexes of participants. RESULTS: Intra-group comparisons indicated that each group had higher levels of NAA/tCr, Glu/tCr, Glx/tCr, and mI/tCr in the right insula, and higher levels of Cho/tCr in the left insula. Inter-group comparisons of the right insula indicated that the JIA-active and JIA-inactive groups had higher levels of Cho/tCr than the HC group, but none of the other inter-group differences were statistically significant. The score of the Sleep Disturbance Scale for Children (SDCD) had an inverse correlation with the level of Cho/tCr in the right insular cortex of patients in the JIA-inactive group. CONCLUSIONS: Relative to the HC group, the right insular cortex of subjects in the JIA-active and the JIA-inactive groups had greater levels of Cho/tCr, suggesting increased inflammation in this region. The Cho/tCr level in the right insular cortex had an inverse correlation with SDCD score in the JIA-inactive group. Key Points • Healthy controls and JIA patients had higher levels of tNAA/tCr, Glu/tCr, Glx/tCr, and mI/tCr in the right insula, and higher levels of Cho/tCr in the left insula. • A greater level of Cho/tCr in the right insula of JIA-active and JIA-inactive patients indicated neuroinflammation in this region. • The Cho/tCr level in the right insular cortex had an inverse correlation with SDCD score in the JIA-inactive group.

Efficacy and safety of etanercept biosimilar rhTNFR-Fc in Chinese patients with juvenile idiopathic arthritis: An open-label multicenter observational study.

Background: Etanercept biosimilar recombinant human TNF-α receptor II: IgG Fc fusion protein (rhTNFR-Fc) has showed its efficacy and safety in Chinese patients with rheumatoid arthritis. However, data on rhTNFR-Fc's application in juvenile idiopathic arthritis (JIA) is limited. Methods: A prospective, observational, multicenter study was performed at 6 institutes in China from July 2020 to December 2021. In a 24-week follow-up, patients with JIA including polyarticular JIA and enthesitis related arthritis received rhTNFR-Fc plus methotrexate (MTX) treatment. The primary outcome parameters were improvements of cJADAS-10 (clinical Juvenile Arthritis Disease Activity Score), and the secondary outcome parameter was an inactive disease. Results: 60 patients completed at least 12-week follow-up, and 57 completed 24-week follow-up. They had high C reactive protein values (11.6 mg/L) and cJADAS-10 (14.6) at baseline. Thirteen patients had morning stiffness. 33 patients showed synovial thickening, and 34 showed bone marrow edemas on MRI. Ultrasonography demonstrated significant joint effusions in 43 patients. The cJADAS-10 sharply decreased from 14.66 at the baseline to 2.4 at 24 weeks of rhTNFR-Fc therapy, respectively (P < 0.01). About half of patients achieved inactive disease at 24 weeks of therapy. Compared with the baseline, the number of patients with morning stiffness, joint effusions, bone marrow edema and synovial thickening on MRI significantly decreased at 24 weeks. Adverse events were consistent with known side effects of biologic agents. Conclusions: The present study indicated that the combination of rhTNFR-Fc and MTX significantly improve symptoms and disease activity of children with JIA. This study suggests etanercept biosimilar rhTNFR-Fc as an effective and safe therapy for children with JIA.

Evidence of persistent glial cell dysfunction in the anterior cingulate cortex of juvenile idiopathic arthritis children: a proton MRS study.

BACKGROUND: This study aims to investigate whether the neurometabolites of the anterior cingulate cortex (ACC) were distinct in patients with active and inactive juvenile idiopathic arthritis (JIA) using the proton magnetic resonance spectroscopy. METHODS: We measured the levels of total N-acetylaspartate (tNAA), choline (Cho), myo-inositol (ml), glutamate (Glu) and the complex of glutamate and glutamine (Glx) relative to total creatine (tCr) in ACC of each participant. RESULTS: Compared with the healthy controls, a significant decrease of total Cho/tCr and Glx/tCr ratio in ACC occurred in active and inactive JIA group. The tCho/Cr level was negatively associated with the serum level of ESR in active JIA patients. There was no difference in NAA/tCr ratio among the three groups, which may imply that no neuron and axonal losses occurred in either active or inactive JIA patients. CONCLUSIONS: The abnormal neurometabolites in tCho/tCr and Glx/tCr in ACC may indicate that persistent dysfunction of glial cell, while neither neuron nor axonal losses occurred in active and inactive JIA patients.

The Brain Structural-Functional Vulnerability in Drug-Naive Children With Juvenile Idiopathic Arthritis: Insights From the Hippocampus.

Objective: Leveraging an integrative multimodal MRI paradigm to elaborate on the hippocampus-derived structural and functional changes in children and adolescents with juvenile idiopathic arthritis (JIA) and to explore potential correlations within the "joint-inflammation-brain" axis during the period of central neural system (CNS) development. Methods: Twenty-one patients with JIA all completed the multimodal MRI scanning, laboratory tests, and neuropsychological assessments; meanwhile, 23 matched controls were recruited. We then harnessed the spherical harmonics with a point distribution model (SPHARM-PDM) and the ROI-to-voxel functional connectivity (FC) to measure the hippocampal shape and hippocampo-cortical FC patterns. Correlation analysis was performed to explore the potential links in neuroimaging features with disease-related indices. Results: Compared to controls, JIA patients only presented an atrophic tendency in the posterior part of the bilateral hippocampus. The hippocampo-cortical FC revealed the between-group divergences mainly located at the pain matrix, striatum, and temporal lobe. Remarkably, the enhanced FC between the right hippocampus and postcentral cortex is positively correlated with the disability index, while the weakened FC of right anterior hippocampus with right insula and that of left posterior hippocampus with left superior temporal gyrus was inversely related to the erythrocyte sedimentation rate and anxiety status, separately. Conclusion: As with macroscopic damages, the altered functional-connectome patterns of the hippocampus in JIA patients might be more sensitive to detect the early neuropathological changes. Moreover, the functional disturbances were demonstrated associated with the physical disability, inflammation, and emotional status. These findings may enlighten us on the underlying neuropathological mechanism of CNS comorbidities in JIA.