Enthesitis-related arthritis is the most common category of juvenile idiopathic arthritis in Taiwan and presents persistent active disease

Disease activity and treatment in patients with juvenile idiopathic arthritis before transfer to adult care: the first survey in China

Objectives

To analyze disease activity and treatment in patients with juvenile idiopathic arthritis (JIA) before transfer to adult care.

Methods

We retrospectively collected the clinical data of 230 JIA patients (range 14-18 years) in our center from January 2013 to December 2022. We evaluated the clinical features, disease activity, and medication use across various JIA subtypes.

Results

230 patients with JIA were included, and 144 (63%) were male. The distribution of JIA subtypes was dominated by enthesitis-related arthritis (32%), polyarthritis (31%), systemic JIA (27%), and oligoarthritis (10%). Disease activity assessment showed that 87 JIA (38%) were in active disease; while 143 JIA (62%) were in inactive disease, of which 59 patients achieved clinical remission on medicine and 13 patients achieved clinical remission off medicine. Conventional synthetic disease-modifying anti-rheumatic drugs were used in 83% of JIA patients, and biologics in 56%. Clinical characteristics and medication use differed between different subtypes of JIA. The oligoarthritis group had earlier disease onset (P = 0.020) and longer disease duration (P = 0.009) compared to other subtypes. Patients in the RF-positive polyarthritis group had a significantly lower rate of disease inactivity (39%, P = 0.004) than the other subtypes, and a relatively lower proportion of patients achieved clinical remission on medication or discontinuation of medication (18%, P = 0.024).

Conclusions

Some JIA patients were still in active disease before transfer to adult clinics, failing to achieve clinical remission and discontinuation of medication, and required continued treatment. Patients in the RF-positive polyarthritis group were less likely to achieve clinical remission.

Clinical Features and Risk Factors for Early Bone Destruction in Enthesitis-Related Arthritis: A Cohort Study

OBJECTIVES

To explore the clinical characteristics and identify risk factors for early bone destruction in children with enthesitis-related arthritis (ERA).

METHODS

Clinical characteristics were retrospectively analyzed in 85 newly diagnosed cases with ERA at our hospital from January 2019 to December 2021. Logistic regression analyses were performed to identify risk factors for early bone destruction.

RESULTS

In this cohort of 85 ERA patients, early bone destruction was identified in 24.7% (21/85) of cases (ERA-BD group), predominantly affecting the sacroiliac joints (66.7%), knee (14.3%), hip (14.3%), and interphalangeal joints (4.8%). The ERA-BD group exhibited significantly higher rates of polyarticular involvement (≥ 5 joints) compared to the ERA-nBD group (76.2% vs. 12.5%, p < 0.001), with a notably higher incidence of knee joint involvement (66.7% vs. 40.6%, p < 0.05) and sacroiliitis (85.7% vs. 50.0%, p < 0.05). Additionally, the ERA-BD group had a longer disease duration (8.0 vs. 3.5 months, p = 0.009) and elevated C-reactive protein levels (median: 12.3 vs. 4.4 mg/L, p = 0.04). However, no significant differences were observed in ESR or IL-6 levels between the two groups. Multivariate analysis confirmed that polyarticular involvement (OR = 21.39, 95% CI 5.12-89.30) and longer disease duration (OR = 4.06, 95% CI 1.33-12.39) were independent predictors of early bone destruction.

CONCLUSIONS

Our study identifies polyarticular involvement (≥ 5 joints) and longer disease duration as key independent predictors of early bone destruction in ERA, highlighting the need for a shift from joint-specific to systemic risk stratification.

Clinical Impact of HLA-B27 on Juvenile Idiopathic Arthritis: Eighteen Years of Follow-up in the Population-Based Nordic Juvenile Idiopathic Arthritis Cohort

OBJECTIVE

We have previously shown that HLA-B27 was negatively associated with remission status eight years after the onset of juvenile idiopathic arthritis (JIA). We now aimed to study the associations of HLA-B27 with clinical features and disease outcomes 18 years after the onset of JIA.

METHODS

We studied 434 patients from the population-based Nordic JIA cohort. Demographic and clinical data, including remission status, were collected consecutively at baseline, eight years after disease onset, and 18 years after disease onset and presented in relation to HLA-B27 status.

RESULTS

The HLA-B27 status was available for 416 of the 434 participants (96%) and was positive for 93 participants (22.4%), more often in men (P = 0.01). The sacroiliac, hips, and subtalar joints were more frequently involved in individuals who were HLA-B27 positive than in individuals who were HLA-B27 negative. In almost half of the individuals with HLA-B27 positivity and uveitis, the uveitis was asymptomatic. Uveitis, inflammatory back pain, sacroiliitis, arthritis in hip, tarsal, and subtalar joints, and enthesitis during the disease course were all associated with a lower rate of remission off medication. HLA-B27 positivity was significantly associated with a higher risk of not being in remission off medication after 18 years (odds ratio [OR] 2.6), especially in men (OR 5.6).

CONCLUSION

Clinical features related to spondylarthropathies were more common in patients who were HLA-B27 positive and associated with worse outcomes and nonremission 18 years after disease onset, particularly in men. Our results underline the adverse impact of having HLA-B27 positivity on long-term outcomes in individuals with JIA.

Early Anti-Drug Antibodies Predict Adalimumab Response in Juvenile Idiopathic Arthritis

Adalimumab, a TNF-alpha inhibitor, is approved to treat juvenile idiopathic arthritis (JIA), helping control disease activity and reduce flare frequency. This study aims to investigate predictors of treatment response, including anti-drug antibodies. We reviewed 65 JIA patients (mean age 10.47 ± 3.90 years; 61.5% male) receiving adalimumab for an average of 2.64 ± 0.56 years, with demographics, laboratory parameters, therapeutic regimens, and treatment outcomes recorded. Disease status was evaluated using the Wallace criteria up to 36 months post-treatment initiation, and anti-adalimumab antibody levels were measured after 6 months of treatment. Enthesitis-related arthritis was the most common subtype (64.6%). Inactive disease status was achieved by 83.1% of patients, with 59.3% experiencing relapse. Detectable anti-adalimumab antibody at six months (p = 0.023) and temporomandibular joint (TMJ) involvement (p = 0.038) identified those less likely to achieve inactive disease. An antibody level cutoff of 7.426 ng/mL best predicted response (AUC = 0.808; p = 0.008), while high anti-adalimumab antibody levels after treatment (p = 0.032) and an injection intervals over two weeks (p = 0.042) were predictors of future flares. Our results highlight that the presence of anti-adalimumab antibodies six months after treatment is a risk factor for poor response to adalimumab therapy.

Biologics promote catch-up growth in young Juvenile idiopathic arthritis patients with lower body height

BACKGROUND

Juvenile idiopathic arthritis (JIA) is accompanied by growth retardation especially in severe cases. While the use of biologics has shown efficacy in restoring growth impairment, data from Asia are limited. We aim to investigate the growth of JIA patients and identify those who can benefit from the use of biologics in Taiwan.

METHODS

JIA patients who received regular follow-up and treatment at a tertiary medical center in Taiwan between January 2011 and June 2023 were retrospectively reviewed. General demographics and growth parameters, including body height, body weight, and body mass index (BMI), were collected at the time of biologics initiation, then at 6 and 12 months into treatment and they were transformed into z-scores for further analysis.

RESULTS

A total of 104 JIA patients, including 52 biologics-free controls, were enrolled. Enthesitis-related arthritis (ERA) accounted for 51% all cases. The initial z-scores for body height, body weight and BMI were -0.33, -0.35, -0.45, respectively. A significantly higher proportion of biologics-treated patients achieved catch-up growth, defined as a continuous increase in height z-scores 1 year following biologics treatment, compared to the biologics-free controls (38% vs. 12%; p = 0.002) 12 months into treatment. In subgroup analysis, JIA patients with lower initial z-scores for height (p = 0.021), a shorter period between symptom onset and diagnosis (p = 0.026), younger ages at the time of biologics initiation (p < 0.001) and higher accumulative dose of steroid before biologics (p = 0.048) are more likely to achieve catch-up growth. Combining the age at the time of biologics initiation and patients' initial z-score for height may be sufficient to predict catch-up growth following treatment with biologics (AUC = 0.804; p < 0.0001).

CONCLUSIONS

Growth retardation appears limited among JIA patients in Taiwan. Initiation of biologics at a younger age may improve linear growth, especially for patients initially shorter for their age.

Taiwan ocular inflammation society consensus recommendations for the management of juvenile idiopathic arthritis-associated uveitis

We presented the development of a consensus guideline for managing juvenile idiopathic arthritis-associated uveitis (JIAU) in Taiwan, considering regional differences in manifestation and epidemiology. The Taiwan Ocular Inflammation Society (TOIS) committee formulated this guideline using a modified Delphi approach with two panel meetings. Recommendations were based on a comprehensive evidence-based literature review and expert clinical experiences, and were graded according to the Oxford Centre for Evidence-Based Medicine's "Levels of Evidence" guideline (March 2009). The TOIS consensus guideline consists of 10 recommendations in four categories: screening and diagnosis, treatment, complications, and monitoring, covering a total of 27 items. These recommendations received over 75% agreement from the panelists. Early diagnosis and a coordinated referral system between ophthalmologists and pediatric rheumatologists are crucial to prevent irreversible visual impairment in children with JIAU. However, achieving a balance between disease activity and medication use remains a key challenge in JIAU management, necessitating further clinical studies.

Prevalence of HLA-B27, clinical characteristics and treatment outcomes in children with enthesitis-related arthritis

BACKGROUND

Enthesitis-related arthritis (ERA) is a subtype of juvenile idiopathic arthritis with high disease burden. The objectives of this study were to explore the prevalence of HLA-B27, clinical characteristics, and treatment outcomes in children with ERA and compare the differences between HLA-B27 positive and negative patients.

METHODS

A retrospective cohort study at a pediatric rheumatology clinic in a tertiary referral hospital in Bangkok, Thailand, including ERA patients with at least 6 months of follow-up (July 2011-April 2022) was performed. Data were collected from medical records from diagnosis to recent follow-up, assessing disease activity and treatment outcomes, with an analysis comparing HLA-B27 positive and negative patients. Descriptive statistics were used for data analysis.

RESULTS

There were 59 ERA patients with mean age ± SD at diagnosis 11.2 ± 2.5 years, 53 males (89.8%), and positive HLA-B27 in 38 patients (64.4%). The HLA-B27 positive group had significantly higher levels of inflammatory markers at initial diagnosis (p = 0.001), lower baseline hemoglobin (p = 0.001) and hematocrit (p = 0.002), higher disease activity assessed by the Juvenile Spondyloarthritis Disease Activity score at 6 and 12 months of follow-up (p = 0.028 and 0.040, respectively), increased utilization of bridging systemic corticosteroids (60.5% vs. 14.3%, p = 0.001) and anti-TNF (39.5% vs. 9.5%, p = 0.018), and longer duration of methotrexate (median[IQR] 1.7[1.1-3.1] vs. 1.3[0.6-1.9] years, p = 0.040). The HLA-B27 negative group had more prevalent hip arthritis than the positive group at initial diagnosis (66.7% vs. 28.9%, p = 0.005) and during the course of the disease (71.4% vs. 36.8%, p = 0.011).

CONCLUSION

Most of the ERA patients tested positive for HLA-B27. Throughout the follow-up period, these patients demonstrated greater disease activity, greater use of corticosteroids and anti-TNF, and longer duration of methotrexate to control the disease.

Identifying factors associated with substantially reduced adult height in patients with juvenile idiopathic arthritis: a retrospective cohort study

BACKGROUND

Juvenile idiopathic arthritis (JIA), an autoimmune disease affecting children or adolescents and causing joint or systemic symptoms, reportedly has a negative effect on the patients' body height. This study aimed to identify factors attributable to substantially reduced adult height (SRAH) in JIA patients.

METHODS

This single-center retrospective cohort study included patients from 2009 to 2019 in Taiwan. We collected JIA patients aged > 18 years at enrollment with a definite diagnosis and undergoing regular outpatient clinic follow-up or disease remission. Target height difference (THD), defined by adult height minus mid-parental height, was calculated for each patient. The calculation results yielded two groups, of which positive THD was defined as the optimal height (OH group) and those with THD below two standardized deviations as the SRAH group. Descriptive statistics and logistic regression analysis were used to analyze the data.

RESULTS

Of 92 JIA patients, 57 and 12 were in the OH and the SRAH groups. Earlier disease onset, especially before the six-year-old, was noted in the SRAH group (p = 0.026). The distribution of JIA subtypes differed significantly between the two groups (p < 0.001); enthesis-related arthritis was the commonest subtype in the OH group, and systemic JIA was the commonest in the SRAH group. Half of the patients in the SRAH group had an active disease status at enrollment, which was higher than the OH group (50.0% vs. 21.1%, p = 0.066). More patients in the SRAH group had received orthopedic surgery due to JIA (25% vs. 3.5%, p = 0.034). Multiple logistic regression analysis showed that SRAH was independently related to systemic JIA (OR = 37.6, 95%CI 1.2-1210.5; p = 0.041).

CONCLUSION

The subtype of systemic JIA, with its characteristics of early disease onset and active disease status, was the essential factor that significantly impacted adult height.

Epidemiology, Treatment, and Outcomes of Juvenile Idiopathic Arthritis-Associated Uveitis: A Multi-Institutional Study in Taiwan

PURPOSE

To assess the epidemiology, treatment, and outcomes of juvenile idiopathic arthritis (JIA)-associated uveitis (JIA-U) in Taiwan.

METHODS

Retrospective, multicenter database.

RESULTS

Totally, 44 (6.1%) of the 722 JIA patients had uveitis. The mean ages of JIA and JIA-U diagnosis were 10.7 and 11.1 years, respectively. JIA-U patients had more antinuclear antibody presence. Among JIA-U patients, 25 (56.8%) were male, 11 (25.0%) experienced any ocular complication, and 8 (18.2%) received ocular surgery. Inactivity lasting ≥6 months was achieved in 17 (38.6%) patients; however, 11 (25.0%) of those experienced reactivation with a mean of 624.7 days after achieving inactivity. Female had more ocular complications and surgeries.

CONCLUSION

Late age at JIA-U diagnosis and male predominance were distinctive in Taiwan. For patients with inactivity lasting ≥ 6 months was achieved, they still required close follow-up due to the high reactivation rate within 2 years. Female had poorer ocular outcomes.

Advances in the Diagnosis and Treatment of Enthesitis-Related Arthritis

Enthesitis-related arthritis (ERA) represents 5-30% of all cases of juvenile idiopathic arthritis (JIA) and belongs to the spectrum of the disorders included in the group of juvenile spondyloarthritis. In the last decade, there have been considerable advances in the classification, diagnosis, monitoring, and treatment of ERA. New provisional criteria for ERA have been recently proposed by the Paediatric Rheumatology INternational Trials Organisation, as part of a wider revision of the International League of Associations for Rheumatology criteria for JIA. The increased use of magnetic resonance imaging has shown that a high proportion of patients with ERA present a subclinical axial disease. Diverse instruments can be used to assess the disease activity of ERA. The therapeutic recommendations for ERA are comparable to those applied to other non-systemic JIA categories, unless axial disease and/or enthesitis are present. In such cases, the early use of a TNF-alpha inhibitor is recommended. Novel treatment agents are promising, including IL-17/IL-23 or JAK/STAT pathways blockers.

C1-C2 subluxation in enthesitis-related arthritis: two case reports and literature review of ten cases

BACKGROUND

C1-C2 subluxation is a rare complication of enthesitis-related arthritis (ERA). If left untreated, it may lead to functional impairment or cervical spinal cord compression. This study aims to highlight key points regarding the management of C1-C2 subluxation in ERA.

CASE PRESENTATION

We present two cases of C1-C2 subluxation: an 8-year-old boy with ERA and 16-year-old boy with ERA with bilateral sacroiliitis. Ten cases of ERA in the literature were reviewed. The diagnosis of C1-C2 subluxation is mostly based on radiographs and cervical spine computed tomography. All patients were treated with non-steroidal anti-inflammatory drugs. Six ERA patients were treated surgically for cervical fusion. Most ERA patients with sacroiliitis had cervical collar protection. Neurologic abnormalities after treatment were not reported. Despite the use of cervical collar, cervical fusion and persisting ankylosis were found in two ERA patients with sacroiliitis without surgical treatment.

CONCLUSIONS

Cervical spine protection and ruling out spinal cord compression should be prioritized, in addition to controlling the underlying inflammation in ERA. Cervical halter traction may be applied after severe cervical inflammation is excluded. To reduce the risk of complications, early recognition and appropriate treatments of C1-C2 subluxation in ERA are essential.

Disability and disease-related damage in Thai children and adolescents with juvenile idiopathic arthritis

BACKGROUND

Children and adolescents with juvenile idiopathic arthritis (JIA) may suffer from disability and disease-related damage. This study aimed to investigate the prevalence of disability and damage, and identify the factors associated with articular and extra-articular damage in children and adolescents with JIA in a resource-restricted setting in Thailand.

METHODS

This cross-sectional study enrolled JIA patients during June 2019-June 2021. Disability was assessed using the Child Health Assessment Questionnaire (CHAQ) and Steinbrocker classification criteria. Damage was evaluated using the Juvenile Arthritis Damage Index (JADI) and the modified-JADI (mJADI) tools.

RESULTS

There were 101 patients (50.5% female) with median age of 11.8 years. Median disease duration was 32.7 months. Enthesitis-related arthritis (ERA) was the most common subtype (33.7%), followed by systemic JIA (25.7%). Thirty-three (32.7%) patients had delayed diagnosis ≥ 6 months. Moderate to severe disability was found in 20 (19.8%) patients. Patients with Steinbrocker functional classification > class I were seen in 17.9%. Thirty-seven (36.6%) patients had articular damage. Extra-articular complications were observed in 24.8%. Growth failure and striae were the most common complications in 7.8%. Leg-length discrepancy was documented in 5.0%. Ocular damage was found in 1 patient with ERA. Multivariable logistic regression analysis revealed Steinbrocker functional classification > class I (aOR: 18.1, 95% CI: 3.9-84.6; p < 0.001), delayed diagnosis ≥ 6 months (aOR: 8.5, 95%CI: 2.7-27.0; p < 0.001), and ERA (aOR: 5.7, 95%CI: 1.8-18.3; p = 0.004) as independent predictors of articular damage. Systemic corticosteroids use was the independent predictor of extra-articular damage (aOR: 3.8, 95%CI: 1.3-11.1; p = 0.013).

CONCLUSIONS

Disability and disease-related damage was identified in one-fifth and one-third of JIA patients. Early detection and treatment are essential for preventing permanent damage.

Clinical Features and Risk Factors of Uveitis in Korean Children with Juvenile Idiopathic Arthritis: A Retrospective Cohort Study

This study aimed to investigate the clinical features and risk factors of uveitis in Korean children with juvenile idiopathic arthritis (JIA). The medical records of JIA patients diagnosed between 2006 and 2019 and followed up for ≥1 year were retrospectively reviewed, and various factors including laboratory findings were analyzed for the risk of developing uveitis. JIA-associated uveitis (JIA-U) developed in 30 (9.8%) of 306 JIA patients. The mean age at the first uveitis development was 12.4 ± 5.7 years, which was 5.6 ± 3.7 years after the JIA diagnosis. The common JIA subtypes in the uveitis group were oligoarthritis-persistent (33.3%) and enthesitis-related arthritis (30.0%). The uveitis group had more baseline knee joint involvement (76.7% vs. 51.4%), which increased the risk of JIA-U during follow-up (p = 0.008). Patients with the oligoarthritis-persistent subtype developed JIA-U more frequently than those without it (20.0% vs. 7.8%; p = 0.016). The final visual acuity of JIA-U was tolerable (0.041 ± 0.103 logMAR). In Korean children with JIA, JIA-U may be associated with the oligoarthritis-persistent subtype and knee joint involvement.

High prevalence of sacroiliitis and early structural changes in the sacroiliac joint in children with enthesitis-related arthritis: findings from a tertiary centre in Hong Kong

BACKGROUND

Epidemiological studies have demonstrated a wide, unexplained disparity in the prevalence of juvenile idiopathic arthritis (JIA) subtypes depending on geographical location, ethnicity and other factors. Enthesitis-related arthritis (ERA) is more prevalent in Southeast Asia. Axial involvement in ERA patients is increasingly recognised to occur early in the disease course. Inflammation in the sacroiliac joint (SIJ) observed on MRI seems highly predictive of subsequent structural radiographic progression. The resulting structural damage can have significant impacts on both functional status and spinal mobility. This study aimed to evaluate the clinical characteristics of ERA in a tertiary centre in Hong Kong. The primary objective of the study was to provide a comprehensive description of the clinical course and radiological findings of the SIJ among ERA patients.

METHOD

Paediatric patients diagnosed with JIA attending the paediatric rheumatology clinic from January 1990 to December 2020 were recruited from our registry based at the Prince of Wales Hospital.

RESULTS

In our cohort, 101 children were included. The median age of diagnosis was 11 years, interquartile range (IQR) 8-15 years. The median follow-up duration was 7 years (IQR 2-11.5 years). ERA was the most prevalent subtype (40%), followed by oligoarticular JIA (17%). Axial involvement was frequently reported in our cohort of ERA patients. 78% demonstrated radiological evidence of sacroiliitis. Among those, 81% had bilateral involvement. The median duration from disease onset to confirmation of radiological sacroiliitis was 17 months (IQR 4-62 months). Among the ERA patients, 73% had structural changes of the SIJ. Alarmingly, 70% of these patients had already developed radiological structural changes when sacroiliitis was first detected on imaging (IQR 0-12 months). Erosion was the most common finding (73%), followed by sclerosis (63%), joint space narrowing (23%), ankylosis (7%) and fatty change (3%). The duration from symptom onset to diagnosis was significantly longer in ERA patients with SIJ structural changes (9 vs 2 months, p = 0.009), comparing with those without.

CONCLUSION

We found that a high proportion of ERA patients had sacroiliitis and a significant number of them had radiological structural changes during early disease. Our findings illustrate the importance of prompt diagnosis and early treatment in these children.

The effect of TNF treatment uptake on incident hospital admission in Western Australia

OBJECTIVE

Treatment strategies for juvenile idiopathic arthritis (JIA) have shifted significantly over the last 20 years. We examined the effect of the introduction of government-subsidised TNF inhibitor (TNFi) treatment on incident hospitalisation for JIA.

METHODS

Western Australian (WA) hospital data were used to identify patients < 16 years hospitalised with JIA between 1990 and 2012. Changes in the number of patients with an incident hospitalisation, overall admissions and admissions for joint aspiration were examined using join-point regression TNFi dispensing data from 2002-2012 was used to describe defined daily doses (DDD)/1000 population/day.

RESULTS

We included 786 patients (59.2% girls, median age 8 years) with a first-time admission with JIA. The annual incident admission rate was 7.9 per 100,000 person-years (95%CI: 7.3, 8.4) which did not change significantly between 1990 and 2012 (annual percentage change (APC): 1.3, 95%CI: -0.3, 2.8). Annual hospital-based prevalence of JIA reached 0.72/1000 in 2012. DDD for TNFi usage rose steadily from 2003 indicating TNFi usage by 1/2700 children in 2012, while overall admission rates (APC 3.7; 95%CI: 2.3, 5.1) and admission rates for joint injections (APC 4.9%; 95%CI: 3.8, 6.0) also increased significantly in that period.

CONCLUSION

Incident inpatient admission rates for JIA were stable over a 22-year period. The uptake of TNFi was not associated with lower admission rates for JIA, due mainly to an increase in admissions for joint injection. These results indicate a notable but unexpected change in hospital-based management of JIA since the introduction of TNFi therapy in WA, where hospital-based prevalence of JIA is slightly higher than in North America.

Recent updates in enthesitis-related arthritis

Enthesitis-related arthritis (ERA) is a category of juvenile idiopathic arthritis which belongs to the spectrum of diseases that are included in juvenile spondyloarthropathy. In recent years, there have been significant advances in understanding pathogenesis, tools to assess disease activity, early recognition of the axial disease, and targeted therapy using IL-17 inhibitors and small molecule inhibitors. The current narrative review highlights these new advances. Among many hypotheses linking HLA B27 to ERA, one of them is the effect of HLA B27 on gut dysbiosis. However, recent data suggest that gut dysbiosis is probably not determined by HLA B27. Though children present with arthritis and enthesitis, axial disease is present in 50-60% on MRI. Using data-driven approach, discriminative MRI finding for active and chronic diseases has been defined for children. This will help in the early recognition of disease. An abridged version of juvenile spondyloarthropathy disease activity (JSpADA) score without the need for acute phase reactants and Schober test performed as well as the original score may increase its acceptance in routine practice. Secukinumab (anti-IL-17 antibody) has shown a more than 75% response rate in children with ERA and may be a good alternative to anti-TNF therapy. Initial data with tofacitinib also look promising. All these will translate into better outcomes for children with ERA.

Revising diagnosis of juvenile idiopathic arthritis in adults: a single-center retrospective study

The study aimed to assess how many adult patients with juvenile idiopathic arthritis (JIA) treated with biologics fulfill classification criteria for adult rheumatic diseases and to evaluate the course of JIA in adulthood. 138 patients with JIA over 18 years old treated with biologics were included in a cross-sectional observative study. Among 138 adult patients with JIA treated with biologics, 81 patients remained with JIA diagnosis. 57 patients were rediagnosed. 31 patients met the criteria for spondyloarthropathy, among them 18 patients for ankylosing spondylitis, 10 patients for psoriatic arthritis, and 3 patients for non-radiographic axial spondyloarthritis. Rheumatoid arthritis was diagnosed in 24 patients and adults' Still disease in 2 patients. 84 patients of all adults with JIA received one biologic agent, 40 received two biologic agents, and 14 received three or more biologic therapies. 10 patients received biologic agents out of recommendations for JIA. Of the adult JIA patients treated with biologics, 41% met the classification criteria for adult inflammatory diseases. Spondyloarthropathy and rheumatoid arthritis were most commonly diagnosed. Nearly 40% of adult JIA patients required at least one modification of biological treatment. Therefore, it is worth considering a revision of JIA to adult-onset inflammatory disease entities, as it broadens the spectrum of disease-modifying drugs.

Axial involvement in enthesitis-related arthritis: results from a single-center cohort

BACKGROUND

Axial involvement in children with enthesitis-related arthritis (ERA) has characteristics that differ from those of peripheral involvement. This study characterized their clinical characteristics and treatment.

METHODS

Patients with ERA at the Children's Hospital of Nanjing Medical University between January 2018 and December 2020 were included. The ERA cohort was divided into two based on the presence or absence of axial joint involvement. Demographic characteristics, clinical features, and treatments were described and compared.

RESULTS

In total, 105 children with ERA were enrolled (axial ERA, n = 57; peripheral ERA, n = 48). The age at disease onset of the axial group tended to be higher (11.93 ± 1.72 vs. 11.09 ± 1.91 years) and the diagnosis delay was bigger in patients with axial ERA (10.26 ± 11.66 months vs. 5.13 ± 7.92 months). The inflammatory marker levels were significantly higher in patients with axial. There were no differences in HLA-B27 positivity between the groups (34 [59.65%] vs. 28 [58.33%], P > 0.05). Hip involvement was more frequent in the axial group (52.63% vs 27.08%; X² = 7.033). A total of 38 (66.67%) and 10 (20.83%) patients with axial and peripheral ERA, respectively, were treated with biological disease-modifying anti-rheumatic drugs (DMARDs) at diagnosis. The administration of biologics increased gradually in the axial ERA group, peaking at 18 months and decreasing thereafter, whereas that in the peripheral ERA group peaked at 6 months and began to decline thereafter.

CONCLUSIONS

Axial ERA is a persistent active disease and requires a more aggressive treatment. Classification and early recognition of axial involvement may help with timely diagnosis and appropriate management.

Enthesitis-related arthritis: the clinical characteristics and factors related to MRI remission of sacroiliitis

Background

To describe the clinical characteristics and explore the factors related to the MRI remission of sacroiliitis in patients with enthesitis-related arthritis (ERA).

Methods

Patients with ERA from 2018–2022 in our medical center were retrospectively reviewed, which identified according to Pediatric Rheumatology International Trials Organization (PRINTO) criteria. Demographics, clinical characteristics, examinations, and treatments were described. Univariate and multivariate logistic regression models were used to analyze the factors related to MRI remission of sacroiliitis in ERA.

Results

This retrospective study included 160 ERA patients (51.9% male) with a mean onset age of 9.2 ± 3.0 years. There were 144 cases (81.9%) with peripheral arthritis, and the hip, knee, and ankle joints were the most commonly involved joints. Enthesitis occurred in 48 cases (30.0%), and sacroiliitis occurred in 142 cases (88.5%) at diagnosis. Human leukocyte antigen (HLA)-B27 was positive in 33 cases (17.1%), and acute uveitis occurred in 3 cases (1.9%). The majority of patients (93.7%) were treated with disease-modifying anti-rheumatic drugs (DMARDs), and 60% with biologics. Among 62 patients with MRI-defined sacroiliitis, 27 (43.5%) cases showed improvement in the sacroiliac joint lesion after treatment. Multivariate logistic regression analysis showed that duration from onset to diagnosis of less than 3 months (OR = 3.609, 95% CI: 1.068–12.192) and active joints of more than 4 (OR = 4.916, 95% CI: 1.006–24.037) were independent factors.

Conclusion

We highlighted differences in ERA clinical characteristics. Patients with a shorter diagnosis time and more joint involvement improved more significantly in sacroiliac joint lesions after treatment.

Comparison of the outcomes between early and late anti-tumor necrosis factor therapy in patients with enthesitis-related subcategory of juvenile idiopathic arthritis: a multi-center study in Southeast Asia

BACKGROUND

Little is known about the impact of delayed initiation of anti-tumor necrosis factor (TNF) therapy in patients with enthesitis-related arthritis (ERA). Here, we compared the impact of delayed treatment on disease outcomes of ERA patients in Southeast Asia.

RESEARCH DESIGN AND METHODS

This retrospective study enrolled 149 ERA patients from Thailand and Singapore. Early (e-aTNF) and late (l-aTNF) treatment groups received anti-TNF therapy starting at ≤6 months and >6 months, respectively, after diagnosis. Outcomes included mean differences in disease activity parameters, Juvenile Spondyloarthritis Disease Activity (JSpADA) score, Juvenile Arthritis Diseases Activity (JADAS)-10 score, and American College of Rheumatology Pediatric (ACR Pedi) criteria, and the frequency of clinically inactive disease and first flare event.

RESULTS

The mean changes in JSpADA (p = 0.002) and JADAS-10 (p < 0.001) scores over time were significantly higher in the e-aTNF group than in the l-aTNF group. A significantly higher proportion of patients in the e-aTNF group than l-aTNF group satisfied ACR Pedi 100 criteria at 2 years (p = 0.042). All other long-term outcomes were not significantly different between the groups.

CONCLUSIONS

Although early anti-TNF treatment improved disease activity parameters somewhat better than delayed anti-TNF therapy, there was no significant difference in long-term outcomes.

Sacroiliitis at diagnosis as a protective predictor against disease flare after stopping medication: outcomes of a Southeast Asian enthesitis-related arthritis (ERA) longitudinal cohort

OBJECTIVES

To assess short- and long-term outcomes of ERA in a large monocentric cohort in Singapore.

METHODS

Children diagnosed with ERA according to ILAR criteria from 2002 to 2021 were recruited. Nonparametric statistics were used to describe the data. Outcomes were defined according to modified Wallace criteria, and probabilities and predictors were determined using Kaplan-Meier survival and logistic regression analyses.

RESULTS

One hundred fifty-one ERA patients (male 86%; Chinese 81%) were included. The median age at onset was 11.9 years (IQR: 9.4-13.9), and disease duration was 5.3 years (IQR: 2.9-8.4). At diagnosis, 39% of the patients had sacroiliitis. HLA-B27 was positive in 83%, and biologics were used in 72% of the patients. Clinical inactive disease (CID) was achieved in 92% of the patients, of which 27% achieved within 6 months. Sacroiliitis at diagnosis is an unfavorable predictor of early CID at 6 months. Medication was discontinued in one-third of the patients. Favorable predictor of medication withdrawal includes male gender, while unfavorable predictors include positive HLA-B27 and ANA. Two-thirds of the patients with CID had at least one disease flare. Sacroiliitis at diagnosis is a protective predictor of flare after stopping medication.

CONCLUSION

Despite a high proportion of ERA patients achieving CID, only one-third could stop medication with high rates of disease flare. Unfavorable predictors include older age at onset, HLA-B27, and ANA positivity. While sacroiliitis at diagnosis is a negative predictor of CID at 6 months, it is associated with less disease flare after discontinuing medication.

Enthesitis-related arthritis: monitoring and specific tools

OBJECTIVES

In this article, the authors aimed to review the different tools used in the monitoring of enthesitis-related arthritis.

SOURCES

The authors performed a literature review on PubMed, Google Scholar, and Scopus databases. The dataset included the original research and the reviews including patients with enthesitis-related arthritis or juvenile spondylarthritis up to October 2020.

SUMMARY OF FINDING

Enthesitis-related arthritis is a category of juvenile idiopathic arthritis. It is characterized by the presence of enthesitis, peripheral arthritis, as well as axial involvement. The only validated tool for disease activity measurement in juvenile idiopathic arthritis is the Disease Activity Score: It has proven its reliability and sensitivity. Nevertheless, due to an absence of validated evaluation tools, the extent of functional impairment, as well as the children and parents' perception of the disease, could not be objectively perceived. Despite the great progress in the field of imaging modalities, the role they play in the evaluation of disease activity is still controversial. This is partially due to the lack of validated scoring systems.

CONCLUSIONS

Further work is still required to standardize the monitoring strategy and validate the outcome measures in enthesitis-related arthritis.

Juvenile spondyloartropathies

Juvenile spondyloarthropathies (JSpA) are defined as a heterogeneous group of diseases that start before the age of 16, which is associated with peripheral joint (especially large joints of the lower limbs) and axial skeletal (spine and sacroiliac joint) involvement, enthesitis, and human leukocyte antigen (HLA) B27 positivity. Juvenile spondyloarthropathies mainly cover juvenile ankylosing spondylitis (JAS), psoriatic arthritis, reactive arthritis, inflammatory bowel disease-associated arthritis, seronegative enthesopathy, arthropathy syndrome (SEA), and enthesitis-associated arthritis. Symptoms associated with spondyloarthropathies are enthesitis, inflammatory low back pain, dactylitis, nail changes, psoriasis, acute anterior uveitis, and inflammatory bowel disease-related symptoms. In JSpA, axial involvement is rarely seen in the early stages of the disease, in contrast to adult patients with ankylosing spondylitis (AS). The disease usually begins as asymmetric oligoarthritis of lower extremities in children, and axial skeletal involvement can occur in the course of the disease. Although the debate on the classification of juvenile spondyloarthropathies continues due to its initial nonspecific findings and the heterogeneity of the disease phenotype, the International League of Associations Rheumatology (ILAR) classification criteria are the most commonly used pediatric criteria. In that set of criteria, patients with JSpA are mainly classified under enthesitis-related arthritis or psoriatic arthritis group. Since juvenile spondyloarthropathies can cause severe loss of function and long-term sequelae, the main goal in treatment should be suppression of inflammation as early as possible and prevent sequelae.

Frequency of juvenile idiopathic arthritis and associated uveitis in pediatric rheumatology clinics in Turkey: A retrospective study, JUPITER

BACKGROUND

Juvenile idiopathic arthritis (JIA), is the most common pediatric rheumatologic disorder with unknown etiology. Currently, no population-based data are available regarding the distribution of categories and frequency of uveitis in patients with JIA in Turkey. The purpose of this study was to evaluate the frequency of JIA-associated uveitis (JIAU) and distribution of JIA categories in a Turkish JIA cohort.

METHODS

This was a retrospective study of 500 randomized patients in four pediatric rheumatology clinics in Turkey.

RESULTS

Oligoarticular JIA (oJIA) was the most common JIA disease category in this study cohort (38.8%). The frequencies of the other categories were as follows: enthesitis-related arthritis (ERA), 23.2%; rheumatoid factor (RF)-negative polyarthritis, 15.6%; systemic arthritis, 12.2%; juvenile psoriatic arthritis, 5.2%; undifferentiated arthritis, 2.8%; and RF-positive polyarthritis, 2.2%. JIA-associated uveitis was observed in 6.8% of patients at a mean (Standard Deviation, SD) age of 9.1 (3.8) years over a mean JIA disease duration of 4 (1.9) years. Uveitis developed after joint disease, with a mean (SD) duration of 1.8 (1.9) years. Patients with oJIA had the highest rate of uveitis (12.9%) followed by patients with ERA (5.2%) and polyarticular RF-negative disease (3.8%). Compared with persistent oJIA, the extended oJIA category had a > 3-fold higher risk of uveitis (11.3% vs 27.7%; odds ratio, 3.38 [95% Confidence Interval, 1.09-10.4]). The most frequently administered drug after development of uveitis was tumor necrosis factor-alpha inhibitors (38.2%). Five patients (14.7%) had uveitis-related complications that required surgical intervention.

CONCLUSIONS

Turkish pediatric patients with JIA experience a lower frequency of oJIA and higher frequency of ERA than their white European counterparts; the occurrence of uveitis is also somewhat lower than expected. Geographic and ethnic factors may affect these differences and need further investigation.

Associations between HLA-B27 subtypes and outcomes in Thai children with enthesitis-related arthritis

OBJECTIVE

Expression of human leukocyte antigen B27 (HLA-B27) has been identified as a predictor of severe disease in enthesitis-related arthritis (ERA) patients. However, the associations between HLA-B27 subtypes and outcomes of this disease are still unclear. Here, we examined the distributions of HLA-B27 subtypes among ERA patients and the associations with disease outcomes.

METHODS

This was a historical cohort study of ERA patients. Patients were followed from diagnosis to the most recent visit. Relationships between outcomes and the HLA-B27 subtype were assessed by mixed-effect regression, Kaplan-Meier survival, and Cox proportional hazards regression analyses.

RESULTS

Of the 66 ERA patients, 50 HLA-B27-positive (86% male) and 16 HLA-B27-negative (69% male) patients were included in this study. Patients with HLA-B27-positive were classified into HLA-B*27:04-positive (84%), including combined HLA-B*27:04 and HLA-B*27:07 (2%), and HLA-B*27:04-negative (16%), including HLA-B*27:05 (10%), HLA-B*27:06 (2%), HLA-B*27:07 (2%), and HLA-B*27:15 (2%). HLA-B*27:04-positive (83.3%) and HLA-B*27:04-negative patients (100%) had refractory disease more than HLA-B27-negative patients (37.5%, p = 0.001). HLA-B*27:04-negative patients (57%, 1.73 years) had relapsing disease more and earlier than HLA-B*27:04-positive (35%, 5.54 years) and HLA-B27-negative patients (40%, 6.92 years; p < 0.001). Furthermore, HLA-B*27:04-negative was predictors of refractory disease (HR 4.56, 95%CI 1.40-14.87; p = 0.012) and relapsing disease (HR 3.80, 95% CI 1.18-12.30; p = 0.026). The duration before anti-tumor necrosis factor treatment initiation > 1 year was also a predictor of refractory disease (HR 116.08, 95% CI 14.67-918.26; p < 0.001).

CONCLUSION

HLA-B*27:04 was the most common HLA-B27 subtype in Thai ERA patients. HLA-B*27:04-negative was associated with more unfavorable outcomes than HLA-B*27:04-positive and HLA-B27-negative patients. Key Points • Most ERA patients in Thailand had HLA-B27-positive, and HLA-B*27:04 was the most common HLA-B27 allele in these patients. • The outcomes of ERA were associated with the presence of HLA-B27 and its subtypes. • HLA-B*27:04-negative patients had unfavorable outcomes, including refractory and relapsing disease, compared to HLA-B*27:04-positive and HLA-B27-negative patients.

Clinical features in 305 patients with juvenile idiopathic arthritis: A single center Turkish Study

BACKGROUND

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatologic disease of childhood. The various subtypes of JIA differ in clinical features and treatments. The aim of this study was to analyze the frequency of JIA subtypes, patient demographic and clinical features, as well as the rates of macrophage activation syndrome, uveitis, and remission in Turkish JIA patients treated at a single center, and to compare the findings to those in the literature.

METHODS

The files of all JIA patients treated at our pediatric rheumatology department between January 2017 and January 2019 were retrospectively reviewed. Patient demographic, clinical, and laboratory data were obtained from the patients' files and the hospital database.

RESULTS

The study included 305 patients (180 females) with a mean age at onset of 7.83 ± 4.62 years. Among all the JIA subtypes, the most frequent was oligoarthritis (41.6%), followed by enthesitis-related arthritis (29.2%), rheumatoid factor (RF)-negative polyarthritis (13.4%), systemic arthritis (9.5%), RF-positive polyarthritis (2.6%), psoriatic arthritis (2.0%), and undifferentiated arthritis (1.6%). At the time of data collection, 278 patients (91.0%) were in remission, whereas 27 patients (9.0%) had active disease. Macrophage activation syndrome developed in 12 of the 29 (41.0%) systemic arthritis. Uveitis was noted in 32 (10.0%) patients. Biological agents were administered in 142 of the patients.

CONCLUSIONS

The available data indicate that JIA as a whole is a heterogeneous disease with significant variability in course and long-term outcome. As such, each patient should be evaluated according to his / her disease subtype.

Outcomes in Juvenile-Onset Spondyloarthritis

Some studies have suggested children with juvenile onset spondyloarthritis (JoSpA) have a relatively poor outcome compared to other juvenile idiopathic arthritis (JIA) categories, in regards to functional status and failure to attain remission. Thus, in the interest of earlier recognition and risk stratification, awareness of the unique characteristics of this group is critical. Herein, we review the clinical burden of disease, prognostic indicators and outcomes in JoSpA. Of note, although children exhibit less axial disease at onset compared to adults with spondyloarthritis (SpA), 34–62% have magnetic resonance imaging (MRI) evidence for active inflammation in the absence of reported back pain. Furthermore, some studies have reported that more than half of children with “enthesitis related arthritis” (ERA) develop axial disease within 5 years of diagnosis. Axial disease, and more specifically sacroiliitis, portends continued active disease. The advent of TNF inhibitors has promised to be a “game changer,” given their relatively high efficacy for enthesitis and axial disease. However, the real world experience in various cohorts since the introduction of more widespread TNF inhibitor usage, in which greater than a third still have persistently active disease, suggests there is still work to be done in developing new therapies and improving the outlook for JoSpA.

Tapering of Biological Agents in Juvenile ERA Patients in Daily Clinical Practice

Objectives: We aim to evaluate the proportion and characteristics of enthesitis-related arthritis (ERA) patients in whom medications can be withdrawn in daily practice and to analyze the factors associated with flare-ups during medication tapering of these patients.

Methods: We retrospectively reviewed records of patients under 16 years old diagnosed with ERA from April 2001 to March 2020 in one tertiary medical center in Taiwan. Patients were categorized by different medication uses: conventional disease modifying anti-rheumatic drugs (cDMARDs) only and cDMARDs plus biologics. Demographics, laboratory data, presence of uveitis, and medication withdrawal rate were analyzed. Subgroup analysis was performed in the patients with cDMARDs plus biologics to identify factors associated with flare-ups during medication tapering of these patients. Statistical analysis was performed using R (v3.6.0).

Results: There were 75 juvenile ERA patients with a median onset age of 10.28 years old. Nineteen (25.3%) patients used cDMARDs for disease control; 56 (74.7%) patients depended on cDMARDs plus biologics. Poly-articular involvement was noted in 29 (38.7%) patients, and it occurred more frequently in the cDMARDs plus biologics subgroup (cDMARDs only, 5.3%; cDMARDs plus biologics, 53.6%; P = 0.0001). ANA positivity was observed in 18 (24.0%) patients, and it occurred more frequently in the cDMARDs plus biologics subgroup (cDMARDs, 0%; cDMARDs plus biologics, 32.1%; P = 0.0038). The overall medication withdrawal rate was 34.7%, and it occurred more frequently in patients with cDMARDs only (cDMARDs only, 84.2%; cDMARDs plus biologics, 17.9%; P < 0.001). In the subgroup analysis of patients with cDMARDs plus biologics, patients on biologics tapering with flare-up had a significantly longer time interval between disease onset and initiation of cDMARDs (biologics tapering without flare-up: 0.27 (0.11–0.73) years; biologics tapering with flare-up: 1.14 (0.39–2.02) years; ever withdrawing biologics: 0.26 (0.18–0.42) years, P = 0.0104).

Conclusion: Juvenile ERA patients with polyarticular involvement had a higher risk of developing cDMARDs refractory and progressing to biologics use. Patients with a long time interval between disease onset and initiation of cDMARDs were prone to experience flare-up during tapering of biologics.

Enthesitis Related Arthritis in a Longitudinal Southeast Asian Registry: High Prevalence of HLA-B27, Different Sacroiliitis Risk Factors and Less Common Drug-Free Remission

Objective. To describe the clinical characteristics, predictors and treatment of children with Enthesitis Related Arthritis (ERA) in a Singapore longitudinal cohort over 11 years. Methods. ERA patients were recruited from our registry (2009–2019). Nonparametric descriptive statistics including median (interquartile range, IQR) were used to describe data. Kaplan–Meier survival and logistic/Cox regression analyses were used to estimate the probabilities and determine predictors of clinical variables, respectively. The significance level was set at <0.05. Results. One hundred and forty-six ERA patients (87% male, 82% Chinese) were included. Median onset age was 11.9 years (IQR 9.4–14.0) and median disease duration was 4.9 years (IQR 2.6–8.3). Family history of Human Leukocyte Antigen (HLA)-B27 associated diseases was positive in 7.5%. Acute uveitis occurred in 3.4%. Oligoarthritis was present in 89.7%. Hip, knee and ankle joints were among the most common joints involved. One-fourth had enthesitis at diagnosis (Achilles tendon entheses, 82.9%). Sacroiliitis occurred in 61%. Probabilities of sacroiliitis development were 0.364, 0.448 and 0.578 at 1, 2 and 5 years after onset, respectively. Negative HLA-B27, female, older age at onset and hip arthritis at diagnosis were associated with shorter time for sacroiliitis development (p = 0.001–0.049). Methotrexate (MTX) remained the most common disease modifying anti-rheumatic drug (DMARD) used (77.4%). However, 77.9% required anti-TNF (aTNF) therapy secondary to MTX failure. Among MTX-treated sacroiliitis patients, 85.3% failed, requiring aTNF, as compared to 63.2%patients without axial disease. Longer duration to diagnosis (p = 0.038) and MTX use (p = 0.007) predicted aTNF therapy. None had joint deformity. Conclusions. This study underscores differences in ERA clinical characteristics, predictors and treatment responses. Our ERA population had many unique findings but good functional outcomes.

The Multi-Omics Architecture of Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) is highly heterogeneous in terms of etiology and clinical presentation with ambiguity in JIA classification. The advance of high-throughput omics technologies in recent years has gained us significant knowledge about the molecular mechanisms of JIA. Besides a minor proportion of JIA cases as monogenic, most JIA cases are polygenic disease caused by autoimmune mechanisms. A number of HLA alleles (including both HLA class I and class II genes), and 23 non-HLA genetic loci have been identified of association with different JIA subtypes. Omics technologies, i.e., transcriptome profiling and epigenomic analysis, contributed significant knowledge on the molecular mechanisms of JIA in addition to the genetic approach. New molecular knowledge on different JIA subtypes enables us to reconsider the JIA classification, but also highlights novel therapeutic targets to develop a cure for the devastating JIA.

Pregnancy outcomes and perinatal complications of Asian mothers with juvenile idiopathic arthritis - a case-control registry study

BACKGROUNDS

In order to provide juvenile idiopathic arthritis (JIA) patients with better pre-conceptional and prenatal counselling, we investigated the obstetrical and neonatal outcomes among women with Asian descent.

METHODS

Through the linkage of Taiwan National Health Insurance database and National Birth Registry, we established a population-based birth cohort in Taiwan between 2004 and 2014. In a case control study design, first children born to mothers with JIA are identified and matched with 5 non-JIA controls by maternal age and birth year. Conditional logistic regression was used to calculate odds ratios for maternal and neonatal outcomes crude and with adjustment.

RESULTS

Of the 2,100,143 newborn, 778 (0.037%) were born to JIA mothers. Among them, 549 first-born children were included in this research. Our result suggested that babies born to mothers with JIA were more likely to have low birth body weight, with an adjusted OR of 1.35(95% CI: 1.02 to 1.79) when compared to babies born to mothers without. No differences were observed in other perinatal complications between women with and without JIA including stillbirth, prematurity, or small for gestational age. The rate of adverse obstetrical outcomes such as caesarean delivery, preeclampsia, gestational diabetes, postpartum hemorrhage and mortality were also similar between the two.

CONCLUSIONS

Adverse obstetrical and neonatal outcomes were limited among Asian mothers with JIA. Intensive care may not be necessary for JIA mothers and their newborns.