Disease activity trajectories in juvenile dermatomyositis from childhood to adulthood.

OBJECTIVES: To assess whether there are identifiable subgroups of disease activity trajectory in a population of juvenile dermatomyositis (JDM) patients-followed throughout childhood and into adulthood-and determine factors that predict those trajectory groupings. METHODS: This is a retrospective, longitudinal inception cohort of patients with idiopathic inflammatory myopathies, largely JDM. We sought to identify baseline factors that predict membership into different groups (latent classes) of disease activity trajectory. RESULTS: A total of 172 patients (64% females), with median age at diagnosis of 7.7 years, were analyzed. We studied 4,725 visits (1,471 patient-years). We identified 3 latent classes of longitudinal disease activity, as measured by the modified disease activity score (DASm), with distinct class trajectories predicted by DASm at baseline, and by the changes of DASm from either baseline to 3 months or baseline to 6 months (early response to therapy). In the analysis in which DASm at baseline and the changes of DASm from baseline to 6 months are included as predictors, Class 1 (10%) has persistently high disease activity, Class 2 (34%) is characterized by moderate disease activity, and Class 3 (56%) is characterized by individuals with a high early disease activity but an apparently good response to treatment and long-term low disease activity. CONCLUSION: High early disease activity, and treatment resistance in the first few months, predict a more chronic longitudinal course of JDM.

Evaluation of Medication Withdrawal in Patients with Non-systemic Juvenile Idiopathic Arthritis in Japan Using a Web-based Survey.

OBJECTIVE: Although treatments for juvenile idiopathic arthritis (JIA) have seen considerable advancements, there remains a lack of clear guidelines on withdrawing medications. This study aimed to investigate the current strategies for discontinuing non-systemic JIA treatment. METHODS: A web-based questionnaire was distributed to Pediatric Rheumatology Association of Japan members. RESULTS: According to 126 responses, the most significant factors influencing JIA treatment tapering were the duration of clinically inactive disease, medication toxicity, and a history of arthritis flares. Respondents were often cautious about discontinuing medication if symptoms, e.g., 'morning stiffness' or 'intermittent joint pain', persisted. Among subtypes, oligoarticular JIA was more amenable to treatment tapering, whereas rheumatoid factor-positive polyarticular JIA proved less amenable. Most respondents started medication tapering after a continuous clinical inactive duration exceeding 12 months, and >50% of them required >6 months to achieve treatment discontinuation. Additionally, 40% of respondents consistently underwent imaging before treatment tapering. CONCLUSIONS: The relative risks of treatment continuation and withdrawal should be considered, and decisions should be made accordingly. To obtain improved understanding of and more robust evidence for the optimal strategies for safely discontinuing JIA treatment, it is crucial to continue investigations, including long-term outcomes.

Epidemiology conduction of paediatric rheumatic diseases based on the registry database of the Pediatric Rheumatology Association of Japan.

OBJECTIVES: Although epidemiological surveys of paediatric rheumatic diseases in Japan have been conducted, they were single surveys with no continuity. This is the first report of the Pediatric Rheumatology Association of Japan registry database, which was established to continuously collect data for paediatric rheumatic diseases. METHODS: Pediatric Rheumatology International Collaborate Unit Registry version 2 (PRICUREv2) is a registry database established by the Pediatric Rheumatology Association of Japan. The registry data were analysed for the age of onset, time to diagnosis, sex differences, seasonality, and other factors. RESULTS: Our data showed the same trend regarding rates of paediatric rheumatic diseases reported in Japan and other countries. The age of onset was lower in juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis and higher in systemic lupus erythematosus and Sjögren's syndrome. The time to diagnosis was relatively short in JIA and systemic lupus erythematosus but longer in juvenile dermatomyositis and Sjögren's syndrome. Rheumatoid factor-positive polyarticular JIA showed a seasonality cluster with regard to onset. CONCLUSION: PRICUREv2 aided the retrieval and evaluation of current epidemiological information on patients with paediatric rheumatic diseases. It is expected that the data collection will be continued and will be useful for expanding research in Japan.

Clinical practice guidance for juvenile dermatomyositis (JDM) 2018-Update.

Juvenile dermatomyositis is the most common type of juvenile idiopathic inflammatory myopathy mainly affecting the skin and proximal muscles. We have published the Japanese version of 'Clinical practice guidance for juvenile dermatomyositis (JDM) 2018 'consisting of a review of articles in the field and evidence-informed consensus-based experts' opinion on the treatment strategy in collaboration with The Pediatric Rheumatology Association of Japan and The Japan College of Rheumatology under the financial support by 'Research on rare and intractable diseases, Health and Labor Sciences Research Grants'. This article is a digest version of the Japanese guidance.

Primary varicella infection in children with systemic juvenile idiopathic arthritis under tocilizumab therapy.

We report the clinical course and outcome of primary varicella infection in six children with systemic juvenile idiopathic arthritis (sJIA) receiving tocilizumab. None had disseminated or fatal varicella infection, but one patient developed macrophage activation syndrome (MAS) and another had an arthritis relapse. All patients had a significant elevation of serum IL-6 levels, and the two children who developed MAS or arthritis relapse showed high serum IL-18 levels, which could cause a sJIA flare-up.

Clinical significance of subcutaneous fat and fascial involvement in juvenile dermatomyositis.

Objectives: Subcutaneous involvement, including calcinosis and panniculitis, is a more common complication in juvenile dermatomyositis (JDM) than in adult dermatomyositis. Magnetic resonance imaging (MRI) is useful for evaluating disease distribution. We investigated the clinical significance of subcutaneous involvement in JDM. Methods: Thighs and hips in 18 newly diagnosed JDM patients were evaluated with fat-suppression MRI. Bilateral muscle, fascial and subcutaneous fat involvement were scored from 0 to 8 points according to the severity of distribution on MRI. Associations between clinical manifestations, serum muscle enzymes, and MRI scores were also evaluated. Results: Abnormal MRI findings in muscle, fascia and subcutaneous fat were observed in 18, 18, and 10 patients, respectively. Subcutaneous fat scores were significantly higher in early-diagnosed JDM patients (diagnosed less than 2 months from onset) than in late-diagnosed JDM patients (diagnosed later) (p = .025). Serum aldolase was elevated in all patients, although only eight demonstrated elevated serum creatine phosphokinase. Serum aldolase was significantly correlated with MRI scores for subcutaneous fat (p < .0001, ρ = .787) and fascia (p = .013 ρ = 0.574), but not muscle. Additionally, serum aldolase was significantly correlated with serum triglycerides (p = .009, ρ = 0.629). Conclusion: Subcutaneous fat involvement is a characteristic finding in early-diagnosed JDM and correlates with elevated serum aldolase.

Clinical practice guidance for juvenile idiopathic arthritis (JIA) 2018.

Juvenile idiopathic arthritis (JIA) is the most common disease in pediatric rheumatism. There is no specific symptom or examination finding for JIA, and the diagnosis is made by exclusion and differentiation. Because non-pediatric rheumatologists are sometimes involved in medical care, 'proposal for JIA guidance on diagnosis and treatment for primary care pediatricians and non-pediatric rheumatologists' was first published in 2007. In these 10 years, a number of new findings on pathophysiology and treatment of JIA have been published; therefore, we propose this guidance of 2018th edition aiming at updating and standardization of JIA medical care in Japan. This edition included the management of uveitis, macrophage activation syndrome, infectious diseases before and during treatment. Moreover, details of biologics are also described. Although this guidance is tailored to adaptation of examinations and drugs, we do not purpose to limit the physicians' discretion in clinical practice. This guidance should be viewed as recommendations and be individualized according to the condition of the patient. We hope that medical care for JIA will advance and more patients will get benefit based on this guidance. Then, further revisions are needed due to changes in future conditions.

Infliximab for the Treatment of Refractory Kawasaki Disease: A Nationwide Survey in Japan.

OBJECTIVE: To assess the safety and efficacy of infliximab (IFX) for the treatment of patients with Kawasaki disease (KD). STUDY DESIGN: This was a nationwide survey of 274 Japanese institutions exploring how IFX was used to treat patients with KD. The patients' sex, age, treatment course, pre- and post-IFX therapy blood test results, coronary artery lesions (CALs), and adverse events (AEs) were evaluated. RESULTS: We analyzed 434 patients with KD who received IFX between March 2005 and November 2014. The median age at onset was 33 months (range 1-138), and 66 patients (15.2%) were under 1 year old. In all cases, IFX was administered as additional treatment. The median days of illness at the initiation of IFX was 9 days. In 275 patients (63.4%), IFX was administered as third-line treatment, and in 106 patients (24.4%), IFX was administered as fourth-line treatment. Single dose IFX 5 mg/kg was administered to 412 patients (94.9%). After IFX, 363 patients (83.6%) became afebrile within 2 days, and the white blood cell count, percentage of neutrophils, and serum C-reactive protein levels significantly decreased (P < .001), although 119 patients (27.4%) received additional treatment. Before IFX, 132 patients (30.4%) had already developed CALs. In patients without CALs before IFX, 31 patients (10.3%) newly developed CAL after IFX, whereas 32 patients (24.2%) with CAL before IFX showed increased CAL severity. Eighty AEs were observed in 69 patients (15.9%); however, serious AEs were few and reversible. CONCLUSIONS: IFX might be an effective and tolerable treatment for refractory KD.

Usefulness of two interferon-γ release assays for rheumatic disease.

BACKGROUND: The aim of this study was to evaluate the performance of two interferon-γ release assays (IGRA), QuantiFERON-TB Gold In-Tube (QFT-GIT) and T-SPOT.TB, for pediatric patients with rheumatic disease in Japan and to analyze the frequencies of indeterminate test results with these kits. METHODS: An IGRA was performed in 108 patients <20 years old in order to exclude tuberculosis infection at the time of first application of or change of biological agents and immunosuppressants in Yokohama City University Hospital. RESULTS: None of the 108 patients tested had active tuberculosis during the 50 month observation period. Indeterminate results of QFT-GIT and T-SPOT.TB tests were obtained in 9.9% and in 0% of cases, respectively. Indeterminate results were obtained significantly more frequently in patients on prednisolone >0.5 mg/kg and in patients with active underlying disease. Use of biologicals and other immunosuppressants had no effect on these measurements. CONCLUSIONS: IGRA are very useful for excluding tuberculosis infection in patients with rheumatic disease before starting new immunosuppressant therapy. Furthermore, the T-SPOT.TB test was suitable for evaluating latent tuberculosis infection even under immunosuppression, when TB tests are generally hard to perform.

Characteristics of FDG-PET findings in the diagnosis of systemic juvenile idiopathic arthritis.

OBJECTIVE: To examine and delineate inflammatory focus in patients with juvenile idiopathic arthritis (JIA), (18)F-Fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) ((18)F-FDG-PET) was applied to patients with JIA, and the images of these patients were compared. METHODS: Sixty-eight children (59 with systemic JIA (s-JIA) and 9 with polyarticular JIA) were included. The diagnosis of JIA was done to meet the International League of Associations for Rheumatology (ILAR) criteria. After 6-h fasting, whole-body positron emission tomography (PET) scans were acquired 60 min after intravenous injection of 3-5 MBq/kg (18)F-FDG. The interpretation of (18)F-FDG uptake was based on visual characteristics. RESULTS: Two types of PET images were outstanding in s-JIA; one was (18)F-FDG uptake in red bone marrow, such as the spine, pelvis, and long bones as well as spleen (12 cases), and other type was the uptake in the major joints, such as hips, elbows, wrists, knees, and ankles (8 cases). The former findings were correlated with elevated levels of inflammatory markers, while the latter were with significantly increased levels of MMP-3 (p < 0.05). CONCLUSION: There was a noticeable accumulation of (18)F-FDG uptake in bone marrow of s-JIA patients which may indicate the inflammatory focus of this disease and play an important role in the pathogenic basis of arthritis and systemic inflammation of s-JIA.

Pathogenesis of systemic inflammatory diseases in childhood: "Lessons from clinical trials of anti-cytokine monoclonal antibodies for Kawasaki disease, systemic onset juvenile idiopathic arthritis, and cryopyrin-associated periodic fever syndrome".

Inflammation has often been considered to be a nonspecific response and to play a bridging role in the activation of adaptive immunity. However, it is now accepted that inflammation is the product of an independent innate immune system closely linked to the adaptive immune system. The key mediators of inflammation are inflammatory cytokines, as determined by multiple lines of evidence both in vitro and in vivo. Due to the crucial role of inflammatory cytokines in the pathogenesis of autoimmune disorders, anti-cytokine treatment has been developed as a therapy for rheumatoid arthritis, juvenile idiopathic arthritis (JIA), and inflammatory bowel diseases. We recently completed several clinical trials of anti-cytokine treatment for children with systemic inflammatory diseases: anti-IL-6 receptor monoclonal antibody (tocilizumab) for children with two subtypes of JIA (poly-JIA and systemic JIA), anti-TNF-α monoclonal antibody (infliximab) for children with Kawasaki disease, and anti-IL-1-ß monoclonal antibody (canakinumab) for children with cryopyrin-associated periodic syndrome. This review summarizes the basis of inflammation in terms of innate immunity and adaptive immunity in these systemic inflammatory diseases, clinical efficacy, and tolerability of these biologic agents, and attempts to determine the roles of individual inflammatory cytokines in disease pathogenesis.

Mycophenolate mofetil as maintenance therapy for childhood-onset systemic lupus erythematosus patients with severe lupus nephritis.

OBJECTIVES: We evaluated histological changes occurring in renal biopsy specimens, between the time before initial induction therapy and after 12 months' maintenance therapy, as well as changes in laboratory parameters, SLE disease activity (SLEDAI), and dosage of corticosteroid (CS) in childhood-onset systemic lupus erythematosus (SLE) patients treated with mycophenolate mofetil (MMF). METHODS: A retrospective analysis was performed on nine patients diagnosed with childhood-onset SLE and lupus nephritis. They were treated with pulsed mPSL and intravenous cyclophosphamide as induction therapy and MMF (500-1500 mg/day) plus CS as maintenance therapy. Renal biopsy was performed before the initial induction therapy and after 12 months' maintenance therapy. RESULTS: Pathological findings at second biopsy were improved in eight of nine patients (89%). The findings of SLEDAI, urinalysis, and blood tests also showed improvement. CS doses could be tapered satisfactorily. Adverse events were observed in two patients. No patients treated with MMF experienced any disease flares during maintenance therapy. CONCLUSIONS: MMF as maintenance therapy might be useful in that not only the histological findings of lupus nephritis were improved, but also CS doses could be beneficially tapered. Nonetheless, this is a retrospective report of only nine cases and further prospective multicenter studies are necessary.

A national survey on current use of mycophenolate mofetil for childhood-onset systemic lupus erythematosus in Japan.

PURPOSE: To conduct a national survey of systemic lupus erythematosus (SLE) patients treated with mycophenolate mofetil (MMF). Based on current information on the use of MMF, we aimed to evaluate its efficacy and safety for childhood-onset (c-) SLE. TARGET: We evaluated 115 patients by questionnaire on MMF use for c-SLE in medical facilities specializing in pediatric rheumatic and renal diseases. RESULTS: Average age at SLE onset was 10.6 (range, 2-15) years; average age at the time of starting MMF was 12.3 (range, 2-15) years. Average dose per body surface area was 1,059.3 mg/m(2)/day. Corticosteroid dosing was 20.9 mg/day before treatment but 7.7 mg/day after treatment. Laboratory values before and after MMF treatment were as follows: C3 increased from 67.0 to 84.9 mg/dl (p < 0.001), C4 increased from 10.2 to 15.1 mg/dl (p < 0.001), and anti-DNA antibody decreased from 154.2 to 18.4 IU/ml (p < 0.001). 24 adverse events in 21 cases were reported, but MMF was not discontinued in any. CONCLUSIONS: The amount of MMF for c-SLE in Japan is similar to the standard dose in other countries. Reduction of corticosteroid dose and improvement of laboratory values represent efficacy of MMF. The side effects recorded here indicated tolerability of the drug.

Serum levels of anti-SRP54 antibodies reflect disease activity of necrotizing myopathy in a child treated effectively with combinatorial methylprednisolone pulses and plasma exchanges followed by intravenous cyclophosphamide.

We describe the effectiveness of combinatorial therapy with plasma exchanges and methylprednisolone pulses followed by intravenous cyclophosphamide in a young girl with anti-signal recognition particle 54 (SRP54) antibody-associated myopathy. We also use a newly described quantitative assay to demonstrate the close association between the titers of anti-SRP54 antibodies and disease activity. This is the first report of a pediatric patient indicating that the serum levels of anti-SRP54 antibodies are also beneficial for monitoring the disease activity of progressive necrotizing myopathy.

Guidance on the use of canakinumab in patients with cryopyrin-associated periodic syndrome in Japan.

Cryopyrin-associated periodic syndrome (CAPS) is an orphan disease with incidence of about one in 1,000,000 persons. This autoinflammatory disease develops in the neonatal period or early childhood, with various inflammatory symptoms occurring repeatedly throughout the patient's lifetime. It is caused by abnormality of the NLRP3 protein which mediates the intracellular signal transduction mechanism of inflammatory processes, resulting in continuous overproduction of interleukin (IL)-1ß, which induces chronic inflammation and progressive tissue damage. Definitive diagnosis of CAPS is difficult, and treatment has also been difficult because of a lack of effective medications in Japan. Clinical studies of human anti-human IL-1ß monoclonal antibody (canakinumab) treatment were conducted in Japan, and approval was granted for therapeutic use of canakinumab for CAPS in September 2011. Similar to other biological drugs, canakinumab is clinically highly effective. However, sufficient attention to the method of use and adverse drug reactions is necessary. This guidance describes the use of canakinumab in Japan for CAPS in relation to exclusion criteria, method of use, evaluation criteria, and adverse drug reactions.

Difficulties of diagnosing idiopathic hypertrophic pachymeningitis in children: Case report and literature review.

Hypertrophic pachymeningitis (HP) is a rare inflammatory disorder characterised by local or diffuse thickening of the cranial and spinal dura mater. HP occurs owing to idiopathic or secondary causes, including autoimmune disease, infection, and trauma. HP has mainly been reported in adults, with few reported cases in children. We encountered an 11-year-old boy with idiopathic HP who presented with chronic inflammation and daily occipital headache. Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) helped us to diagnose him with HP. He was successfully treated with corticosteroids and azathioprine with no recurrence. We also conducted a literature review of childhood-onset HP and found only 16 cases, including our patient. Seven patients had idiopathic HP, and the remaining nine had secondary HP, including two with rheumatic disease. The most common clinical symptoms were headache (68.8%) and cranial nerve-related symptoms (68.8%). Inflammatory laboratory markers were elevated in 60% of patients with available data. Fifteen cases were diagnosed using Gd-enhanced MRI. The main initial treatment was steroids and/or immunosuppressants, to which 87.5% of patients responded. However, two patients with HP associated with trauma and neuroblastoma (12.5%) died, and seven patients (43.8%) had left cranial nerve-related sequelae. As the prognosis for childhood HP is poor, early diagnosis and treatment are essential. Children with headache, cranial nerve symptoms, and elevated inflammatory marker levels should be suspected of having HP and Gd-enhanced MRI should be considered.

Characteristics of persistent arthritis with refractory Kawasaki disease: a single-center retrospective study.

Arthritis is one complication of Kawasaki disease (KD); however, the clinical features of arthritis in KD have not been well clarified. We retrospectively investigated the characteristics of persistent arthritis beyond the subacute phase of KD. In this cohort, 49 of 243 patients (20%) developed arthritis, with 33 patients (14%) experiencing persistent arthritis. Among these 33 patients, 31 (94%) had complete KD. Thirty (91%) were resistant to first intravenous immunoglobulin, and 15 (45%) required additional infliximab. Five patients (15%) developed coronary artery lesions, and 24 (73%) had oligoarthritis, mainly in large lower-extremity joints. Twenty-four patients (73%) complained of arthralgia. At arthritis onset, 16 patients (48%) presented with fever, including recurrent fever in 10 patients. Serum C-reactive protein concentration in patients with active arthritis significantly increased compared with after acute KD treatment (2.4 vs. 0.7 mg/dL, p < 0.001). Serum matrix metalloproteinase-3, a biomarker of arthritis, was significantly higher in patients with active arthritis than in remission (93.7 vs. 20.3 ng/mL, p < 0.001). Thirty (91%) and 14 (42%) patients, respectively, were treated with non-steroidal anti-inflammatory drugs and prednisolone, and they completely recovered. To summarize, persistent arthritis is a common complication in refractory KD, and adequate diagnosis and treatment are necessary.