Uveitis as predictor of disease flare after the first anti-TNF withdrawal in oligoarticular and polyarticular juvenile idiopathic arthritis: a multicentric Italian experience.

OBJECTIVES: TNF inhibitors (TNFi) have dramatically changed the prognosis of juvenile idiopathic arthritis (JIA), but it is not clear how and when stop therapy. We aim to describe a multicentric cohort of JIA treated with adalimumab or etanercept who discontinued the treatment for persistent inactivity and to identify factors associated with relapse. METHODS: In a multicentric Italian retrospective cohort study, medical records of patients with oligoarticular and polyarticular JIA were evaluated if they stopped therapy for persistent inactivity after the first TNFi. RESULTS: 136 patients were enrolled (102 female, median age at onset 3 years (range 1-15), of whom 55.9% had oligoJIA, 40.4% uveitis and 72.8% ANA positivity. Adalimumab (59.3%) and etanercept (40.7%) were started at a median age of 6 years (range 1-16), TNFi were discontinued after a median time of 30 months (range 6-90), increasing the interval (76.5%), reducing the dose (18.4%) and abrupt discontinuation (16.9%). 79.4% of patients relapsed after a median time of 5 months (range 0.5-66). Patients with uveitis relapsed earlier (log rank χ² 16.4 p<0.0001), while patients who lengthened the interval of administration showed a later relapse (log rank χ² 6.95 p=0.008). Uveitis (HR 2.11 CI 1.34-3.31), age at onset (HR 0.909 CI 0.836-0.987), duration of tapering (HR 0.938 CI 0.893-0.985) and to have a persistent OligoJIA (HR 0.597 CI 0.368-0.968) are significant predictors of disease relapse (Mantel-Cox χ² 34.23 p<0.001). CONCLUSIONS: Younger age at onset, uveitis, duration of tapering, and not-persistent OligoJIA seem to be independent risk factors for earlier relapse after the first TNFi withdrawal.

Convergence and divergence in Kawasaki disease and multisystem inflammatory syndrome in children: results from the COVASAKI survey.

OBJECTIVES: To compare Kawasaki disease (KD) and multisystem inflammatory syndrome (MIS-C) in children. METHODS: Prospective collection of demographics, clinical and treatment data. Assessment of type 1 interferon (IFN) score, CXCL9, CXCL10, Interleukin (IL)18, IFNγ, IL6, IL1b at disease onset and at recovery. RESULTS: 87 patients (43 KD, 44 MIS-C) were included. Age was higher in MIS-C compared to KD group (mean 31±23 vs. 94±50 months, p<0.001). Extremities abnormalities (p=0.027), mucosal involvement (p<0.001), irritability (p<0.001), gallbladder hydrops (p=0.01) and lymphadenopathy (p=0.07) were more often recorded in KD. Neurological findings (p=0.002), gastrointestinal symptoms (p=0.013), respiratory involvement (p=0.019) and splenomegaly (p=0.026) were more frequently observed in MIS-C. Cardiac manifestations were higher in MIS-C (p<0.001), although coronary aneurisms were more frequent in KD (p=0.012). In the MIS-C group, the multiple linear regression analysis revealed that a higher IFN score at onset was related to myocardial disfunction (p<0.001), lymphadenopathy (p=<0.001) and need of ventilation (p=0.024). Both CXCL9 and CXCL10 were related to myocardial disfunction (p<0.001 and p=0.029). IL18 was positively associated to PICU admission (0.030) and ventilation (p=004) and negatively associated to lymphadenopathy (0.004). IFNγ values were related to neurological involvement and lymphadenopathy (p<0.001), IL1b to hearth involvement (0.006). A negative correlation has been observed between IL6 values, heart involvement (p=0.013) and PICU admission (p<0.001). CONCLUSIONS: The demographic and clinical differences between KD e MIS-C cohorts confirm previous reported data. The assessment of biomarkers levels at MIS-C onset could be useful to predict a more severe disease course and the development of cardiac complications.

Revising the value of Antistreptolysin O titre in childhood and its interpretation in the diagnostic approach of rheumatic diseases.

The burden of group A streptococcus (GAS) infection and its rheumatic sequelae remains dramatically high, especially in low-income countries. Recently, an increased number of Acute Rheumatic Fever (ARF) cases was documented in many regions of Italy. The diagnosis of rheumatic sequelae relies on clinical signs and on the evaluation of the Antistreptolysin O titre (ASO), whose variations are globally reported. To re-examine the standard reference value of ASO titre, by measuring either its upper limit of normal (ULN) in a population of healthy children (HC) or comparing these values with streptococcal antibodies registered in a cohort of patients affected by the rheumatic sequelae of GAS infection. We performed a multicenter retrospective study. We enrolled 125 HC, aged 2-17 years, and a total of 181 patients affected by ARF, acute streptococcal pharyngitis, post-streptococcal arthritis, Henoch-Schönlein purpura and erythema nodosum, divided into four groups. The levels of ASO and anti-deoxyribonuclease B (anti-DNase B) titres were analyzed and compared among the various groups. Moreover, the 80th percentile value was calculated and established as the ULN for ASO titre in HC group. The ULN for ASO titre in overall HC group was 515 IU/mL, resulting in higher than used in the routine investigation. The ASO titre was significantly higher in patients with rheumatic sequelae compared with HC group, with a peak in the age between 5 and 15 years.    Conclusion: Our study established a new ULN normal value of streptococcal serology in a childhood and adolescent population of Italy, suggesting the need to extend this revaluation to the critical areas, in order to avoid underestimating ARF diagnosis. The correct interpretation of ASO and anti-DNase B values in the context of rheumatic diseases has been discussed. What is Known: • The global burden of disease caused by group A streptococcus is not known and remains an important cause of morbidity and mortality. Acute rheumatic fever continues to be a serious worldwide public health problem and a recent recurrence of group A streptococcus infection cases is observed. • The streptococcal sequelae requires evidence of preceding streptococcal infection, commonly elevated streptococcal antibody titre, but the upper limit for these titres varies considerably based on age group, region, and origin. What is New: • This study provides population-specific values for streptococcal antibody titres in Italy. • Interpret the results of group A streptococcal antibody tests within the clinical context.

Acute hemorrhagic edema of infancy: 20-year experience from an Italian tertiary referral center.

PURPOSE: Data on acute hemorrhagic edema of infancy (AHEI) are derived from small case series or case reports. We report a 20-year experience at a national referral center. METHODS: We performed a single-center retrospective study including patients who were diagnosed with AHEI from January 1, 2004, to June 30, 2023. RESULTS: We identified 21 patients (57.1% females) with a median age of 18 months (range 7-33 months). Thirteen (61.9%) patients were admitted to the pediatric ward, the remaining eight (38.1%) presented to the emergency department and were discharged for outpatient management. The median length of hospitalization was 5 days (range 3-9 days). Twenty patients (95.2%) had prodromal symptoms. The most common cutaneous findings were targetoid purpuric plaques. The lesions were most localized on the face (13, 61.9%) and on the upper limbs (18 patients, 85.7%). Sixteen (76%) patients presented with nonpitting and tender edema, localized on the feet (9/16, 56%) and hands (6/16, 37.5%). Systemic involvement was rare, and no patients experienced complications or sequelae. Twelve (57.1%) patients underwent infectious disease investigations, with positive results in only four (33.3%). None of the patients diagnosed after the SARS-CoV-2 outbreak (March 2020) had positive nasopharyngeal swabs for the virus. For the 13 patients who were admitted to the pediatric ward, the median length of hospitalization was five days (3-9 days). CONCLUSIONS: The 21-patient single-center cohort of children affected by AHEI confirmed a generally benign course of AHEI, despite a 62% rate of hospitalization.

Behçet syndrome in children and adults: discovering similarities and differences by a comparative study.

OBJECTIVE: Behçet's syndrome (BS) is a rare disorder with a relapsing-remitting course. Clinical variance across geographical regions and different age groups has been observed. This study matched the demographic, clinical and treatment features of adult- and juvenile-onset BS in the Italian population. METHODS: Two clinical databases of BS patients were compared. The paediatric BS database was collected at the Meyer Children's Hospital, Florence, while the adult BS database was collected at the Careggi University Hospital, Florence. RESULTS: A familiar predisposition for BS was significantly more frequent in the paediatric cohort (3/33 vs 1/165, P = 0.015). No difference emerged in terms of prevalence of HLA-B51 positivity. The proportion of patients meeting the revised ICBD and/or the ISG criteria at BS diagnosis was comparable in the two cohorts. No significant difference emerged between the two cohorts in terms of muco-cutaneous, ocular and neurological involvement, and gastrointestinal symptoms. Articular manifestations resulted as more common in the paediatric cohort, whereas venous vascular events were more frequent in the adult cohort. Regarding treatment strategy, paediatric patients more frequently received no treatment or corticosteroid monotherapy. Conversely, the use of DMARDs, both traditional and biologic, was significantly higher in the adult cohort. CONCLUSION: Remarkable differences between juvenile-onset and adult-onset BS, both in terms of gender, familiar predisposition and clinical manifestations have been observed and a different therapeutic approach in the real clinical practice of the two settings emerged. Prospective, comparison studies with a longer follow-up are encouraged to provide further data about the disease course for juvenile- and adult-onset BS.

CD38high/HLA-DR+ CD8+ T cells as potential biomarker of hemophagocytic lymphohistiocytosis secondary to visceral Leishmania infection.

Leishmaniasis is a cause of infection associated with hemophagocytic lymphohistiocytosis (HLH). The measurement of the CD8+ CD38high/HLA-DR+ T cells in children presenting with acute onset of shock and multisystem organ failure represents an important parameter to distinguish HLH from sepsis or healthy control. CONCLUSION: We report a case series of 4 Italian children suffering from HLH secondary to visceral Leishmaniasis in which the lymphocyte subset assay suggests a potential role of CD38high/HLA-DR+ CD8+ T cells as HLH diagnostic biomarkers. WHAT IS KNOWN: • Visceral Leishmaniasis is a well-known cause of infection associated with hemophagocytic lymphohistiocytosis (HLH). • The measurement of the CD8+ CD38high/HLA-DR+ T cells in children presenting with acute onset of shock and multisystem organ failure represents an important diagnostically useful parameter to readily distinguish HLH from sepsis or healthy controls. WHAT IS NEW: • We report a case series of 4 Italian children suffering from HLH secondary to visceral Leishmaniasis in which the lymphocyte subset assay suggests a potential role of CD38high/HLA-DR+ CD8+ T cells as HLH diagnostic biomarker. • The flow cytometry assay, performed at the disease onset before starting treatment, revealed a mean percentage value of CD38 cells of 36.95% among CD8+ T cells.

STAT3-confusion-of-function: Beyond the loss and gain dualism.

BACKGROUND: Germline mutations of signal transducer and activator of transcription 3 (STAT3) are responsible for 2 distinct human diseases: autosomal-dominant hyper-IgE syndrome (AD-HIES) caused by STAT3 loss-of-function mutations and STAT3 gain-of-function disease. So far, these entities have been regarded as antithetic, with AD-HIES mainly associated with characteristic infections and a connective tissue phenotype and STAT3 gain-of-function characterized by lymphoproliferation and poly-autoimmunity. The R335W substitution in the DNA-binding domain of STAT3 was initially described in 2 patients with typical AD-HIES, but paradoxically, recent functional analysis demonstrated a gain-of-function effect of this variant. OBJECTIVES: A patient with Sjögren syndrome and features of AD-HIES with this mutation is described and the molecular consequences are further characterized. METHODS: This study provides a clinical and immunological description of the patient. STAT phosphorylation in primary patient cells was studied and A4 cells transfected with the patient allele were used to study phosphorylation kinetics, transcriptional activity, and target-gene induction. RESULTS: The hybrid clinical features of the patient were associated with normal TH17 cells. Enhanced and prolonged STAT3 phosphorylation, an increased STAT3 driven luciferase reporter activity upon IL-6 stimulation, but reduced IL-6-induced SOCS3 production were all observed. CONCLUSIONS: The germline R335W-STAT3 variant displays a mixed behavior in vitro that mainly shows gain-of-function, but also loss-of-function features. This is matched by an ambiguous clinical and immunological phenotype that dismantles the classical antithetic dualism of gain- versus loss-of-function. Germline STAT3 mutation-related disease represents a pathological spectrum with the p.R335W associated phenotype locating between the 2 recognized clinical disease patterns.

Clinical Syndromes Related to SARS-CoV-2 Infection and Vaccination in Pediatric Age: A Narrative Review.

This narrative review aims to report the main clinical manifestations, therapeutic strategies, outcomes, and complications of acute SARS-CoV-2 infection in childhood and to summarize the data relating the SARS-CoV-2 vaccination efficacy and safety in pediatric age. SARS-CoV-2 infection mostly occurs asymptomatically in the pediatric population, while multisystem inflammatory syndrome in children (MIS-C) represents the most severe coronavirus disease 2019 (COVID-19)-related illness, a life-threatening event with a high morbidity rate. After the development of SARS-CoV-2 vaccines and their subsequent approval in children, the rate of infection as well as the number of its related complications have shown a drastic decrease. Fully vaccinated children are protected from the risk of developing a severe disease and a similar protective role has been observed in the reduction of complications, in particular MIS-C. However, long-lasting immunity has not been demonstrated, booster doses have been required, and reinfection has been observed. With regards to vaccine safety, adverse events were generally mild to moderate in all age groups: local adverse events were the most commonly reported. Nevertheless, a potential association between SARS-CoV-2 vaccine and the subsequent development of inflammatory manifestations has been suggested. Myocarditis has rarely been observed following vaccination; it appeared to be more frequent among adolescent males with a mild clinical course leading to a complete recovery. SARS-CoV-2 vaccine-related MIS-C cases have been described, although a univocal definition and an exact time interval with respect to vaccination has not been reported, thus not establishing a direct causal link. Current evidence about COVID-19 vaccination in children and adolescents suggest that benefits outweigh potential risks. Long-term data collection of the post-authorization safety surveillance programs will better define the real incidence of SARS-CoV-2 vaccine-related complications in the pediatric population.

OBSIDIAN - real-world evidence of originator to biosimilar drug switch in juvenile idiopathic arthritis.

OBJECTIVES: Limited data about use of biosimilars (BIOs) are available in children with JIA. This study therefore aimed to evaluate long-term efficacy and safety of switching from etanercept (ETA) and adalimumab (ADA) originators to their biosimilars (BIOs), in children with JIA, in a real-world setting. METHODS: This is a retro-prospective non-interventional multicentre Italian comparative cohort study. Medical charts of JIA children treated with biosimilars of ETA or ADA were included. Efficacy and safety of TNF-inhibitors therapy was evaluated at last follow-up during originator and at 3, 6 and 12 months following the switch to biosimilar. RESULTS: A total of 59 children (42 female, median age at onset 88 months) were treated with biosimilar of ETA (21) and ADA (38). Forty-five switched from the originator to the BIO (17 ETA, 28 ADA). At time of switch, 12/17 patients on ETA and 18/28 on ADA were in remission. No significant difference has been found at 3, 6 and 12 months after the switch. Ten patients discontinued biosimilars due to disease remission (4 ETA, 3 ADA), family willing (1 ETA), occurrence of burning at injection site (1 ETA) and persistent activity (1 ADA). No statistically significant difference was observed between originator and BIOs, nor between originator and BIOs, and between ADA and ETA in time to disease remission achievement, time to relapse and number of patients who experienced adverse event (AE). CONCLUSION: Our real-life results seem to confirm the efficacy and safety profile of switching from originator of ADA and ETA to their respective BIOs, also in paediatric patients with JIA.

A systematic review on biological therapies in juvenile idiopathic inflammatory myopathies: an evidence gap in precision medicine.

OBJECTIVES: Juvenile idiopathic inflammatory myopathies (JIIMs) are a heterogeneous group of systemic autoimmune diseases. Juvenile dermatomyositis (JDM) is the predominant form of JIIMs, and is a rare, chronic autoimmune illness characterised by symmetric, proximal muscle damages and involvement of the skin. In the last two decades, the use of monoclonal antibodies has also been expanded to JIIMs; however, there is limited evidence on use of these treatments. We assessed the efficacy/effectiveness and safety of biologic agents in JIIMs. METHODS: A systematic literature review was conducted using Embase®, MEDLINE®, MEDLINE®-In Process and Cochrane library to identify studies on biologics agents in JIIMs published in English language as full-text articles (1975 to December 2020) or conference abstracts (2000 to December 2020). Databases were searched with the key words regarding chronic myositis crossed with "biologic agents OR tocilizumab OR rituximab OR adalimumab OR infliximab OR anti-TNF OR etanercept". Of note, we did not include children, age, or age limits in the search as medical subject headings terms because we may have been able to extract a sub cohort of children from studies including both children and adults. RESULTS: Of the 1633 retrieved publications, 18 articles were identified for a total of 165 patients. In real-world studies, definition of complete (CR) or partial response (PR) varied. JIIMs patients were most often treated with anti-TNF (88 pts); patients received etanercept (ETA), 48 patients infliximab (IFX), 4 patients received adalimumab (ADA). In other 15 patients IFX was followed by ADA. Rituximab (RTX) was used in 73 children. A single case series reported the use of abatacept (ABA) in 4 patients. Despite the reduced number of treated patients, complete response on myositis was reported in 29.6% (8/26) patients treated with at least one anti-TNF and in 38% (10/26) treated by RTX. Complete response of skin vasculitis has been reached in 33% (4/12) children on anti-TNF and in 36% on RTX (21/58). Anti-TNF agents might be efficient in treating calcinosis lesions. CONCLUSIONS: Currently, the available evidence regarding the use of biologic treatment in JIIMs results quite limited but suggest a promising the use of anti-TNF agents and RTX in treating active JIIMs. Anti-TNF treatment might have a role in treating calcinosis. However, an overall very low quality of the available studies and multiple confounding factors hamper to suggest a treatment over another. Thus, randomised clinical trials are urgently required to attempt the optimal treatment in real-world setting.

Adjunctive treatment with infliximab in pediatric immunoglobulin A (IgA) vasculitis: A case report.

Immunoglobulin A vasculitis (IgAV) is the most common childhood vasculitis affecting small vessels. No clear recommendations are available for severe pediatric cases, and until now, anti-TNF agents have had a limited role in IgAV management. In this report, we describe a pediatric case of severe IgAV, successfully treated with combined therapy including the anti-TNF, infliximab.

Growth and body mass index in a cohort of patients with juvenile idiopathic arthritis: effects of second line treatments.

OBJECTIVES: Juvenile idiopathic arthritis (JIA) may affect natural growth. The aim of the study has been to assess auxological parameters of JIA patients, receiving different anti-rheumatic treatments. METHODS: This is a retrospective study; JIA patients were recruited from the Rheumatology Unit of Anna Meyer Children's University Hospital of Florence, Italy from March 1996 to June 2016. RESULTS: Two hundred and thirty-two patients were included in the current study. The best result in terms of catch-up growth occurred in systemic JIA patients. All JIA categories showed standard deviation score (SDS) gain for height except those belonging to enthesitis related arthritis category. Patients treated with disease-modifying anti-rheumatic drugs (DMARDs) only maintained constant growth during study follow-up. Patients who needed biologic therapy showed an impaired growth during pre-DMARDs treatment and an increased growth velocity mostly during biologic therapy. Body mass index (BMI) decreased in almost all JIA categories. The best BMI reduction was observed among patient receiving biologic drugs. CONCLUSIONS: Patients with JIA followed in our centre had a gain of height SDS and lost BMI SDS in 5 years of follow-up. We observed a stable and good pattern of growth in patients treated with DMARDs and an increased growth velocity during biologic treatment.

Immunosuppressive Activity of Abatacept on Circulating T Helper Lymphocytes from Juvenile Idiopathic Arthritis Patients.

BACKGROUND: Abatacept is used in the treatment of juvenile idiopathic arthritis (JIA) patients, but the activity of the drug on T helper cell function is not yet fully known. METHODS: The ability of abatacept to affect cytokine production in vitro and the proliferative response to both recall antigens and polyclonal stimulation was firstly assessed in healthy donors. Then, 10 JIA patients who were due to start abatacept treatment were recruited and longitudinally evaluated during the first 90 days of therapy. Both their clinical response to the treatment and in vitro analysis aimed to assess the proliferative response to recall antigens and the proportions of circulating T helper subsets. RESULTS: Abatacept reduced the proliferative response to recall antigens and the production of proinflammatory cytokines such as IFN-γ and TNF-α in healthy donors in vitro. It was also efficient in improving symptoms and reducing parameters of inflammation in JIA patients. Abatacept reduced the proliferative response to recall antigens, and this effect was significant soon after drug infusion (2 days). Regarding the proportions of circulating CD4+ T lymphocytes, only a reduction in the frequencies of circulating Treg cells was observed. CONCLUSIONS: Abatacept in vitro inhibits proliferation and cytokine production in healthy donors, and reduces parameters of inflammation in vivo in JIA patients. The reduction of the proliferative response to recall antigens induced by abatacept was evident only soon after drug administration, suggesting that its immunosuppressive activity is maintained only for a short time.