Serum calprotectin and joint ultrasound in the definition of disease relapse in non-systemic juvenile idiopathic arthritis: a prospective longitudinal study.

OBJECTIVES: The aim of our study was to investigate the role of serum calprotectin (SC) and muscle-skeletal ultrasound (MSUS) as predictive markers of relapse in patients with juvenile idiopathic arthritis (JIA). METHODS: Sixty non-systemic (ns) JIA patients in clinical remission were recruited to evaluate the risk of disease relapse. SC levels and JIA disease activity were assessed at every visit (3, 6, 12 and 18 months). Joint synovitis, characterised by both synovial effusion (SE) and synovial hyperplasia (SH), was measured by US score (sum of SE, SH, power Doppler and bone erosions) given to each examined joint and US ratio (US score/number of joints examined) at every visit. Associations of SC, US score and US ratio with relapse prevalence was studied longitudinally by using generalised estimating equations model. RESULTS: Thirty-one (51.6%) patients relapsed within 18 months. Patients with higher baseline US scores showed higher risk of relapse at 6 months (OR (95% confidence interval (CI)): 1.96 (1.09-3.52)). Additionally, patients with higher SC values at baseline showed higher risk of relapse at 18 months (1.66 (1.13-2.44)). Patients with higher baseline SC values showed an increased overall odds of relapse up to 18 months of follow-up (1.21 (1.08-1.36)). Furthermore, patients with higher US scores showed an increased overall odds of relapse up to 18 months of follow-up (1.96 (1.56-2.46)). Similarly, patients with higher US ratio showed an increased overall odds of relapse up to 18 months of follow-up (16.62 (7.17-38.54)). CONCLUSIONS: SC was able to identify JIA patients with unstable remission and increased risk of relapse. MSUS represents an interesting additional tool to the clinical evaluation, especially in predicting early relapse.

The Role of Serum Calprotectin in Defining Disease Outcomes in Non-Systemic Juvenile Idiopathic Arthritis: A Pilot Study.

Serum calprotectin (MRP8/14) is currently being studied as a promising biomarker of disease activity and outcome in patients with juvenile idiopathic arthritis (JIA) but the data in the literature are conflicting. The aim of our study was to investigate the potential role of serum calprotectin as biomarker of disease activity and flare/remission in a group of nsJIA patients during a follow-up period of 18 months. In this prospective longitudinal study, two groups of patients with ns-JIA (55 active patients and 56 patients in remission according to Wallace's criteria) and a control group (50 children) were recruited at baseline from January 2020 to September 2021. JIA patients were followed for up to 18 months at four timepoints: 3 months (T1), 6 months (T2), 12 months (T3) and 18 months (T4). At each timepoint, the following were recorded: JADAS27, blood counts, ESR, CRP, albumin, ferritin and serum calprotectin. To illustrate the performance of calprotectin, Kaplan-Meier curves were constructed from baseline to relapse/remission, dichotomizing patients at baseline in positive/negative on the basis progressive calprotectin cut-offs. Associations between baseline factors and relapse were determined using Cox regression models. Multivariate models were constructed to analyze the effect of covariates. Comparing baseline clinical and laboratory data of the three groups (active vs. inactive JIA vs. controls), only serum calprotectin reached statistical significance (active patients vs. inactive (p = 0.0016) and vs. controls (p = 0.0012)). In the inactive group, during the 18 months of follow up, 31 patients (55.3%) had a relapse. Comparing the baseline data of relapsers vs. non-relapsers, serum calprotectin showed higher levels (p = 0.001) in relapsers. In survival analysis, a log rank test showed significant differences of up to 12 ng/mL (p = 0.045). Multivariate Cox regression confirmed that only baseline calprotectin levels were independently associated with disease recurrence. In the active group, in the 12 months of follow-up, 19 patients (38%) entered remission of the disease. In addition, in this group, the only statistical difference at the baseline was the value of MPR8/14 (p = 0.0001). Log rank test showed significant differences up to 10 ng/mL (p = 0.003). In the multivariate Cox regression, serum calprotectin levels at baseline were independently associated with remission. In conclusion, our study would suggest a dual role for calprotectin in predicting future relapse and treatment response in patients with nsJIA, thus influencing therapeutic decisions and management of these patients during follow up.

Bone Health in Children with Rheumatic Disorders: Focus on Molecular Mechanisms, Diagnosis, and Management.

Bone is an extremely dynamic and adaptive tissue, whose metabolism and homeostasis is influenced by many different hormonal, mechanical, nutritional, immunological and pharmacological stimuli. Genetic factors significantly affect bone health, through their influence on bone cells function, cartilage quality, calcium and vitamin D homeostasis, sex hormone metabolism and pubertal timing. In addition, optimal nutrition and physical activity contribute to bone mass acquisition in the growing age. All these factors influence the attainment of peak bone mass, a critical determinant of bone health and fracture risk in adulthood. Secondary osteoporosis is an important issue of clinical care in children with acute and chronic diseases. Systemic autoimmune disorders, like juvenile idiopathic arthritis, can affect the skeletal system, causing reduced bone mineral density and high risk of fragility fractures during childhood. In these patients, multiple factors contribute to reduce bone strength, including systemic inflammation with elevated cytokines, reduced physical activity, malabsorption and nutritional deficiency, inadequate daily calcium and vitamin D intake, use of glucocorticoids, poor growth and pubertal delay. In juvenile arthritis, osteoporosis is more prominent at the femoral neck and radius compared to the lumbar spine. Nevertheless, vertebral fractures are an important, often asymptomatic manifestation, especially in glucocorticoid-treated patients. A standardized diagnostic approach to the musculoskeletal system, including prophylaxis, therapy and follow up, is therefore mandatory in at risk children. Here we discuss the molecular mechanisms involved in skeletal homeostasis and the influence of inflammation and chronic disease on bone metabolism.

Monogenic Autoinflammatory Diseases: State of the Art and Future Perspectives.

Systemic autoinflammatory diseases are a heterogeneous family of disorders characterized by a dysregulation of the innate immune system, in which sterile inflammation primarily develops through antigen-independent hyperactivation of immune pathways. In most cases, they have a strong genetic background, with mutations in single genes involved in inflammation. Therefore, they can derive from different pathogenic mechanisms at any level, such as dysregulated inflammasome-mediated production of cytokines, intracellular stress, defective regulatory pathways, altered protein folding, enhanced NF-kappaB signalling, ubiquitination disorders, interferon pathway upregulation and complement activation. Since the discover of pathogenic mutations of the pyrin-encoding gene MEFV in Familial Mediterranean Fever, more than 50 monogenic autoinflammatory diseases have been discovered thanks to the advances in genetic sequencing: the advent of new genetic analysis techniques and the discovery of genes involved in autoinflammatory diseases have allowed a better understanding of the underlying innate immunologic pathways and pathogenetic mechanisms, thus opening new perspectives in targeted therapies. Moreover, this field of research has become of great interest, since more than a hundred clinical trials for autoinflammatory diseases are currently active or recently concluded, allowing us to hope for considerable acquisitions for the next few years. General paediatricians need to be aware of the importance of this group of diseases and they should consider autoinflammatory diseases in patients with clinical hallmarks, in order to guide further examinations and refer the patient to a specialist rheumatologist. Here we resume the pathogenesis, clinical aspects and diagnosis of the most important autoinflammatory diseases in children.

Growth and puberty in children with juvenile idiopathic arthritis.

Juvenile Idiopathic Arthritis is one of the most prevalent chronic diseases in children, with an annual incidence of 2-20 cases per 100,000 and a prevalence of 16-150 per 100,000. It is associated with several complications that can cause short-term or long-term disability and reduce the quality of life. Among these, growth and pubertal disorders play an important role. Chronic inflammatory conditions are often associated with growth failure ranging from slight decrease in height velocity to severe forms of short stature. The prevalence of short stature in JIA varies from 10.4% in children with polyarticular disease to 41% of patients with the systemic form, while oligoarthritis is mostly associated with localized excessive bone growth of the affected limb, leading to limb dissymmetry. The pathogenesis of growth disorders is multifactorial and includes the role of chronic inflammation, long-term use of corticosteroids, undernutrition, altered body composition, delay of pubertal onset or slow pubertal progression. These factors can exert a systemic effect on the GH/IGF-1 axis and on the GnRH-gonadotropin-gonadic axis, or a local influence on the growth plate homeostasis and function. Although new therapeutic options are available to control inflammation, there are still 10-20% of patients with severe forms of the disease who show continuous growth impairment, ending in a short final stature. Moreover, delayed puberty is associated with a reduction in the peak bone mass with the possibility of concomitant or future bone fragility. Monitoring of puberty and bone health is essential for a complete health assessment of adolescents with JIA. In these patients, an assessment of the pubertal stage every 6 months from the age of 9 years is recommended. Also, linear growth should be always evaluated considering the patient's bone age. The impact of rhGH therapy in children with JIA is still unclear, but it has been shown that if rhGH is added at high dose in a low-inflammatory condition, post steroids and on biologic therapy, it is able to favor a prepubertal growth acceleration, comparable with the catch-up growth response in GH-deficient patients. Here we provide a comprehensive review of the pathogenesis of puberty and growth disorders in children with JIA, which can help the pediatrician to properly and timely assess the presence of growth and pubertal disorders in JIA patients.

Pediatrician's approach to diagnosis and management of group A streptococcal pharyngitis.

Group A streptococcal (GAS) pharyngitis is responsible for 20-30% of pharyngitis cases in children (Shulman et al. Clin Infect Dis 55(10):e86-e102, 2012). Recommendations for the diagnosis and treatment of GAS pharyngitis have been published by the Italian National Institute of Health guidelines in 2012 (ESCMID Sore Throat Guideline Group et al. Clin Microbiol Infect 18(Suppl 1):1-28, 2012). Adherence to such guidance is relevant for primary prevention of complications of GAS pharyngitis, above all rheumatic fever (RF). The aim of our study was to evaluate the application of Italian guidelines by the family pediatricians from the Abruzzo region. A validated questionnaire was completed by the family pediatricians and used for data collection. The 154 family pediatricians from Abruzzo (88% of the total number of family pediatricians) participated in the study. Out of the 1232 answers, 455 (37%) were wrong. Only 8% of the participants answered correctly all the questions, whereas 0.6% missed all the questions. Through the Spearman's correlation, our study found an inverse significant correlation between the questions regarding primary prophylaxis (Score B) and the work experience of pediatricians (Rho = - 0.276, p = 0.048). The majority of the family pediatricians from the Abruzzo region, in line with studies from other countries, have significant knowledge gaps about the diagnosis and treatment of GAS pharyngitis. Therefore, strategies to increase the pediatricians' awareness of the guidelines are needed, in order to reduce the RF incidence.