Examining the Relationship between Systemic Immune-Inflammation Index and Disease Severity in Juvenile Idiopathic Arthritis

Juvenile Idiopathic Arthritis (JIA), the leading childhood rheumatic condition, has a chronic course in which persistent disease activity leads to long-term consequences. In the era of biologic therapy and tailored treatment, precise disease activity assessment and aggressive intervention for high disease activity are crucial for improved outcomes. As inflammation is a fundamental aspect of JIA, evaluating it reflects disease severity. Recently, there has been growing interest in investigating cellular immune inflammation indices such as the neutrophil-to-lymphocyte ratio (NLR) and systemic immune inflammation index (SII) as measures of disease severity. The aim of this retrospective study was to explore the potential of the SII in reflecting both inflammation and disease severity in children with JIA. The study comprised 74 JIA patients and 50 healthy controls. The results reveal a notable increase in median SII values corresponding to disease severity, exhibiting strong correlations with traditional inflammatory markers, including CRP and ESR (ρ = 0.714, ρ = 0.661), as well as the JADAS10 score (ρ = 0.690). Multiple regression analysis revealed the SII to be independently associated with JADAS10. Furthermore, the SII accurately distinguished patients with high disease activity from other severity groups (AUC = 0.827, sensitivity 81.5%, specificity 66%). These findings suggest that integrating the SII as an additional measure holds potential for assessing disease activity in JIA.

MicroRNAs in Juvenile Idiopathic Arthritis: State of the Art and Future Perspectives

Juvenile Idiopathic Arthritis (JIA) represents the most common chronic pediatric arthritis in Western countries and a leading cause of disability in children. Despite recent clinical achievements, patient management is still hindered by a lack of diagnostic/prognostic biomarkers and targeted treatment protocols. MicroRNAs (miRNAs) are short non-coding RNAs playing a key role in gene regulation, and their involvement in many pathologies has been widely reported in the literature. In recent decades, miRNA's contribution to the regulation of the immune system and the pathogenesis of autoimmune diseases has been demonstrated. Furthermore, miRNAs isolated from patients' biological samples are currently under investigation for their potential as novel biomarkers. This review aims to provide an overview of the state of the art on miRNA investigation in JIA. The literature addressing the expression of miRNAs in different types of biological samples isolated from JIA patients was reviewed, focusing in particular on their potential application as diagnostic/prognostic biomarkers. The role of miRNAs in the regulation of immune responses in affected joints will also be discussed along with their potential utility as markers of patients' responses to therapeutic approaches. This information will be of value to investigators in the field of pediatric rheumatology, encouraging further research to increase our knowledge of miRNAs' potential for future clinical applications in JIA.

Biomarkers in Systemic Juvenile Idiopathic Arthritis, Macrophage Activation Syndrome and Their Importance in COVID Era

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset-such as non-remitting high fever, headache, rash, or arthralgia-and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care-a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS-so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.

Association between PTPN22 C1858T polymorphism and juvenile idiopathic arthritis: A meta-analysis update with trial sequential analysis

Our aim was to determine whether protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism (rs2476601) is associated with susceptibility to juvenile idiopathic arthritis (JIA). MEDLINE and EMBASE databases were searched to identify articles in which PTPN22 C1858T polymorphism was reported to be identified in JIA patients and controls. A meta-analysis was conducted to evaluate the association between PTPN22 C1858T polymorphism and RA using allelic contrast. Trial sequential analysis (TSA) was performed. Sixteen separate comparisons involving 5696 JIA patients and 9483 controls (a total of 15,179 subjects) were considered in this meta-analysis. A meta-analysis was performed with all JIA patients as well as JIA patients in each ethnic group. Meta-analysis revealed an association between the T allele of PTPN22 C1858T polymorphism and JIA in all subjects (OR, 1.322; 95% CI, 1.233-1.418; p < .001). Analysis after stratification by ethnicity indicated that the T allele was significantly associated with JIA in the European population (OR, 1.312; 95% CI, 1.2211-1.410; p < .001). However, analysis performed in the non-European population showed no significant association between the T allele and JIA. TSA indicated that the observed association between the PTPN22 polymorphism and JIA in all subjects and the European population is consistent with the existing evidence. This meta-analysis confirms that PTPN22 C1858T polymorphism is associated with susceptibility to JIA in Europeans, and that no additional studies are needed to verify these results. However, current evidence in the non-European population is insufficient, and further studies are warranted.