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.

Childhood mixed connective tissue disease at disease onset: Evidence from a systematic review.

OBJECTIVE: Childhood Mixed Connective Tissue Disease (cMCTD) is the rarest pediatric connective tissue disease that includes features of systemic lupus erythematosus, polymyositis/dermatomyositis, juvenile idiopathic arthritis, and systemic sclerosis, identified by Sharp in 1972 and whose diagnosis remains challenging. This systematic review aims to identify clinical features at the onset of cMCTD and manifestations not currently included into the available diagnostic criteria. METHODS: A systematic literature review was performed in accordance with PRISMA guidelines 2020 using bibliographic databases: MEDLINE via PubMed and EMBASE. ELIGIBILITY CRITERIA: patients diagnosed with MCTD with onset before 18 years. STUDIES INCLUDED: registries, retrospective and prospective cohort studies, case series and reports with analysis of data on signs and symptoms of presentation. RESULTS: 39 articles were included (215 subjects, 82.5% female), mean age of 141 months (± 41 months DS, range 2.5-204). The most used criteria for the diagnosis of MCTD were the Kasukawa criteria (54.5%). The clinical manifestations described at onset were Raynaud's phenomenon (69.7%), arthritis (60.9%), muscular involvement (53.5%), dermatological signs (39.5%), swollen fingers or hands (29.3%), arthralgias (25.6%), fever (22.3%), lung involvement (14.4%), sclerodactily (13.5%), lymphadenopathy (10.7%) serositis (10.2%), esophageal involvement (6.9%), nervous system involvement (6.9%), xeroftalmia (3.7%), xerostomia (3.7%), hepatosplenomegaly (2.8%), cardiac involvement (2.8%), hepatitis (2.3%), parotiditis (2.3%), Hashimoto's thyroiditis (0.9%), ocular involvement (0.9%). CONCLUSIONS: The data from this systematic review suggest great heterogeneity of the clinical presentation of cMCTD for which there are no validated diagnostic criteria that may suggest a new diagnostic approach to allow earlier or more accurate diagnosis in the future.

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.

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.

Laser Flare Photometry to Monitor Childhood Chronic Uveitis: A Preliminary Report of a Monocentric Italian Experience.

Background: Childhood chronic non-infectious uveitis (cNIU) is a challenging disease that needs close monitoring. Slit lamp evaluation (SLE) is the cornerstone of ophthalmological evaluation for uveitis, but it is affected by interobserver variability and may be problematic in children. Laser flare photometry (LFP), a novel and objective technique, might be used in children with uveitis. Aim: The aim of this study was to attempt the use of LFP in cNIU clinical practice. Methods: Children, attending the Rheumatology Unit and who were scheduled to receive ophthalmological evaluation, were prospectively enrolled to concomitantly receive SLE and LFP. SLE was performed blind to LFP measure. Demographic, laboratory, clinical, and ophthalmology data were collected. Results: A total of 29 children (58 eyes) were enrolled, including 3 with juvenile idiopathic arthritis without uveitis (JIA-no-U), 15 with JIA-associated uveitis (JIA-U), and 11 with idiopathic chronic uveitis (ICU). We observed significantly higher LFP values in the eyes of children with uveitis compared to the others (10.1 IQR 7.1-13.6 versus 6.2 IQR 5.8-6.9, p = 0.007). Accordance between the SLE and LFP measures, at baseline (ρ.498, p < 0.001) and during the follow-up (LFP II ρ 0.460, p < 0.001, LFP III ρ 0.631, p < 0.001, LFP IV ρ 0.547, p = 0.006, LFP V ρ 0.767, p = 0.001), was detected. We evaluated significant correlation between LFP values and the presence of complications (ρ 0.538, p < 0.001), especially with cataract formation (ρ 0.542, p < 0.001). Conclusions: In this cohort, LFP measurements showed a good correlation with SLE. LFP values showed a positive correlation with the presence of complications. LFP might be considered as a reliable objective modality to monitor intraocular inflammation in cNIU.

Lung involvement in juvenile idiopathic inflammatory myopathy: A systematic review.

OBJECTIVE: Juvenile idiopathic inflammatory myopathies (JIIM) are a group of connective tissue disorders characterized by muscle inflammation and variable systemic involvement, including interstitial lung disease (ILD). Available data on JIIM-associated ILD are very limited. We performed a systematic review of the available clinical, laboratory, and radiological features of JIIM-associated ILD. METHODS: A systematic literature review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS: A total of 90 patients were identified, of whom 77.8% had JDM, 10% amyopathic JDM, 7.8% anti-synthetase syndrome, 3.3% overlap syndrome, and 1.1% juvenile polymyositis. Anti-melanoma differentiation-associated gene 5 (MDA-5/CADM-140) was the most frequently reported myositis-specific antibody (32.2%). At diagnosis of ILD, 55.5% of patients had respiratory symptoms. Ground glass opacity was the most reported radiological feature (52.9%). Thirty-three % of patients developed rapidly progressive (RP) lung disease; 26.7% were admitted to the intensive care unit (ICU); 28.9% died; all deaths were due to ILD, with a median interval of 2 months (IQR 1.5-4.7) between the onset of respiratory symptoms and death. Patients admitted to the ICU and who died of ILD were more likely to be male, to have a rapidly progressive pattern, progression of radiological features, and a higher level of KL-6. CONCLUSIONS: MDA-5/CADM-14 is associated with RP-ILD. ILD is a rare but severe manifestation among the spectrum of systemic involvement associated with JIIM, with a high rate of ICU admission and mortality. Early recognition and aggressive treatment are needed to prevent a severe outcome.

Thrombotic Events in MIS-C Patients: A Single Case Report and Literature Review.

Multisystem Inflammatory Syndrome in Children (MIS-C) is a systemic hyperinflammatory disorder that is associated with a hypercoagulable state and a higher risk of thrombotic events (TEs). We report the case of a 9-year-old MIS-C patient with a severe course who developed a massive pulmonary embolism that was successfully treated with heparin. A literature review of previous TEs in MIS-C patients was conducted (60 MIS-C cases from 37 studies). At least one risk factor for thrombosis was observed in 91.7% of patients. The most frequently observed risk factors were pediatric intensive care unit hospitalization (61.7%), central venous catheter (36.7%), age >12 years (36.7%), left ventricular ejection fraction <35% (28.3%), D-dimer >5 times the upper limit of normal values (71.9%), mechanical ventilation (23.3%), obesity (23.3%), and extracorporeal membrane oxygenation (15%). TEs may concurrently affect multiple vessels, including both arterial and venous. Arterial thrombosis was more frequent, mainly affecting the cerebral and pulmonary vascular systems. Despite antithrombotic prophylaxis, 40% of MIS-C patients developed TEs. Over one-third of patients presented persistent focal neurological signs, and ten patients died, half of whom died because of TEs. TEs are severe and life-threatening complications of MIS-C. In case with thrombosis risk factors, appropriate thromboprophylaxis should be promptly administered. Despite proper prophylactic therapy, TEs may occur, leading in some cases to permanent disability or death.

Anti-IL17 treatment in childhood chronic rheumatic diseases.

INTRODUCTION: Interleukin-17 (IL-17) is a family of cytokines that plays a key role in several rheumatic diseases in both adults and children. In the last few years, several drugs targeting IL-17 have been developed. AREAS COVERED: We present a review on the current state of the art regarding the use of anti-IL17 in childhood chronic rheumatic diseases. To date, the available evidence is limited and mainly focuses on juvenile idiopathic arthritis (JIA) and a specific autoinflammatory disease called deficiency of IL-36 receptor antagonist (DITRA). Recently, a randomized controlled trial resulted in the approval of secukinumab (an anti-IL17 monoclonal antibody) for JIA, due to its demonstrated efficacy and safety. Promising and potential uses of anti-IL17 in Behçet's syndrome and synovitis acne pustulosis hyperostosis osteitis (SAPHO) syndrome have also been described. EXPERT OPINION: Increasing knowledge about the pathogenetic mechanisms underlying rheumatic diseases is leading to an improvement in the care of several chronic autoimmune diseases. In this scenario, anti-IL17 therapies (such as secukinumab and ixekizumab) might be an optimal choice. Recent data on the use of secukinumab in juvenile spondyloarthropathies can be a starting point for future treatment strategies in other pediatric rheumatic diseases, such as Behçet's syndrome and the chronic non-bacterial osteomyelitis disease spectrum, particularly SAPHO syndrome.

Challenges and management of childhood noninfectious chronic uveitis.

INTRODUCTION: Childhood uveitis is a sight-threatening condition, because if not properly recognized and treated can lead to several ocular complications and blindness. It represents a real challenge not only from an etiologic/diagnostic point of view, but also for management and therapy. AREAS COVERED: In this review we will discuss the main etiologies, the diagnostic approach, risk factors associated to childhood noninfectious uveitis (cNIU), and the difficulties in eye examination in childhood. Moreover, we will discuss the treatment of cNIU in terms of therapeutic choice, timing of initiation, and withdrawal. EXPERT OPINION: Identification of specific diagnosis is mandatory to prevent severe complications, thus a thorough differential diagnosis is essential. Pediatric eye examination may be extremely challenging due to the scarce collaboration, but novel techniques and biomarkers will help in identifying low grade of inflammation, eventually modifying long-term outcomes. Once identified the appropriate diagnosis, recognition of children who may benefit of a systemic treatment is crucial. What, When, and how long are the key questions to address in this field. Current evidence and future results of ongoing clinical trials will help in driving treatment. A proper ocular screening, not only in the context of systemic disease, should be discussed by experts.

Concomitant Use of Elexacaftor/Tezacaftor/Ivacaftor and Etanercept in a Cystic Fibrosis Patient with Juvenile Idiopathic Arthritis.

Patients with cystic fibrosis often complain of joint manifestations. However, only a few studies have reported the association between cystic fibrosis and juvenile idiopathic arthritis and addressed the therapeutic challenges of these patients. We describe the first paediatric case of a patient affected by cystic fibrosis, Basedow's disease and juvenile idiopathic arthritis who was contemporarily treated with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) and anti-tumor necrosis factor α (anti-TNFα). This report seems to reassure regarding the potential side effects of these associations. Moreover, our experience suggests that anti-TNFα is an effective option in CF patients affected by juvenile idiopathic arthritis, and is even safe for children receiving a triple CFTR modulator.

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.

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.

Neuro-PIMS-TS: a single case report and review of the literature.

Neurological manifestations related to SARS-CoV-2 infection in adults have been largely reported since the beginning of the pandemic. Subsequent large-scale studies involving children confirmed the occurrence of neurological symptoms associated with SARS-CoV-2 infection also among paediatric patients, especially in the context of paediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS-TS). At this regard, we report the challenging case of a 10-month-old baby with PIMS-TS complicated by acute cerebral oedema successfully treated with intravenous immunoglobulins, corticosteroids and anakinra. Our results, combined with the evidence of larger case series suggest that higher inflammatory burden is more frequent in patients with neuro PIMS-TS. As regards neuroimaging, neuroimmune disorders are found to be more common during acute COVID-19, MERS is more frequent during PIMS-TS. Distinct immune mechanisms may underlie these different types of neurological involvement, which are yet to be understood. Further studies are required to better define the physiopathology of neuro PIMS-TS and its possible therapeutical implications.

Pseudo-rheumatic manifestations of limping: Camptodactyly-arthropathy-coxa vara-pericarditis syndrome: Single case report and review of the literature.

Camptodactyly-arthropathy-coxa vara-pericarditis (CACP) syndrome is a rare genetic disease characterized by tetrad camptodactyly, noninflammatory arthropathy, coxa vara deformity, and pericardial effusion. Arthropathy typically affects large joints and presents with joint swelling in the absence of other signs of inflammation. We described the case of a girl affected by CACP syndrome caused by a novel compound heterozygous variant in proteoglycan 4 gene (c.2831_2832insT; c.3892C > T) and associated with temporomandibular involvement. The patient received treatment with intra-articular hyaluronic acid injections, which presented rapid but transient improvements of pain and range of motion. A literature review of previously reported CACP patients has been performed. Of the patients. 69.2% (101 out of 146) were Middle Eastern, and 65.7% (96) were consanguineous. The median age of onset was 24 months (interquartile range of 12-36 months), and median age of diagnosis was 96 months (interquartile range of 48-156 months). Arthropathy was always present, mainly involving hips (95.2%), knees (92.4%), wrists (87.7%), elbows (79.5%), and ankles (57.5%). Camptodactyly and pericardial effusion were described, respectively, in 97.3% (142) and 15.1% (22) of patients. The main radiological findings were coxa vara (95.2%), femoral changes (64.4%), intraosseus cysts (14.4%), and bone erosion (5%). Of the patients, 32.9% (48) had received a previous juvenile idiopathic arthritis diagnosis. CACP syndrome can be easily misdiagnosed with juvenile idiopathic arthritis. A prolonged lack of response to immunosuppressive therapy associated with typical clinical and radiological features should prompt consideration of this rare syndrome.

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.