Pediatric Society of the African League Against Rheumatism juvenile idiopathic arthritis recommendations for enthesitis-related arthritis and juvenile psoriatic arthritis

The objective of this study is to develop evidence-based recommendations for the diagnosis and management of enthesitis-related arthritis (ERA) and juvenile psoriatic arthritis (JPsA) in the African context. The recommendations for ERA and JPsA were combined into a single document. The steering committee and task force identified 15 key questions and formulated 35 research questions. A comprehensive literature review, utilizing Medline and a manual search for African local data, was conducted to gather evidence. Following this synthesis, the task force developed draft recommendations and engaged in a Delphi process with an expert panel, including 17 African and three international experts, to reach a consensus and ensure alignment with global standards. The final recommendations were assigned a level of evidence and subsequently approved by the task force members, the expert panel, and the PAFLAR Board. Fifteen recommendations on the diagnosis and management of ERA and JPsA were developed, covering the role of the pediatric rheumatologist in multiple aspects of disease management, including diagnosis, monitoring of disease and extra-articular manifestations, determining treatment strategies, and guiding interventions. The level of evidence supporting these recommendations was variable, leading to the identification of a research agenda to address African particularities and answer pending questions. The final recommendations achieved a high level of agreement, with consensus ranging from 90 to 100%. These recommendations represent an important achievement for pediatric rheumatology in Africa, being the first of their kind, tailored specifically to the region. Developed through a rigorous methodology and collaboration between international and African experts, they aim to standardize care and address the unique challenges faced in African setting.

Do the features of juvenile psoriatic arthritis change according to age? A comprehensive evaluation of the PeRA Research Group Registry

OBJECTIVES

To describe the clinical features and treatment outcomes of children with juvenile psoriatic arthritis (JPsA) and compare the distinct patterns of the disease between early-onset and late-onset age groups.

METHODS

Patients with JPsA followed regularly for at least 6 months between 2010 and 2020 in seven paediatric rheumatology centres in Turkey were included in the study. The demographic features, clinical manifestations, treatment strategies and outcomes of the patients were evaluated retrospectively.

RESULTS

A total of 87 (46 male/41 female) patients were included in the study. The mean age at diagnosis was 11.9 years (s.d. 4.5). Fifty-seven (65.5%) patients had psoriasis at the time of diagnosis and arthritis preceded psoriasis in 10 (11.5%) patients. Thirty (34.5%) patients had dactylitis, 28 (32.2%) had nail pitting, 36 (41.4%) had involvement of the small joints and 20 (23%) had enthesitis. Sacroiliitis was detected in 11 (12.6%) patients by MRI. ANA was positive in 35 (40.2%) patients. Twelve children (13.8%) were in the early-onset (<5 years) group. Uveitis and ANA positivity were more common in the early-onset group. Active joint counts and activity scores of our patients showed significant improvement at month 6 and at the last control compared with baseline.

CONCLUSION

About one-third of patients with JPsA do not have psoriasis at the time of diagnosis. In some patients, no skin lesion is seen during the course of the disease. Children with PsA seem to display two different phenotypes. Younger children have a female predominance, ANA positivity and uveitis, while older children have more axial involvement.

Existing and Emerging Targeted Therapies in Juvenile Psoriatic Arthritis: Challenges and Unmet Needs

Juvenile psoriatic arthritis (JPsA) is a heterogeneous type of non-systemic chronic inflammatory arthritis affecting children and young people. This review focuses on highlighting challenges in harmonising recommendations for the use of available therapies in JPsA, according to its distinct clinical phenotypes, and explores the similarities and differences between the disease classification and management across age. We further explore the emerging therapeutic landscape, summarising the recently completed clinical trials in JPsA, and ongoing studies in both JPsA and adults with psoriatic arthritis, highlighting unmet needs and barriers for translational research in JPsA. The novel therapeutic agents in clinical development in JPsA range from monoclonal antibodies targeting interleukin (IL)-17, IL-12/23 and IL-23 blockades to synthetic small molecules targeting Janus kinase and tyrosine kinase and phosphodiesterase-4 inhibition. In addition, there are head-to-head clinical trials comparing tumour necrosis factor-α blockade with both IL-17 and IL-23 inhibition. Most of these new therapies have been tested in adults with psoriatic arthritis and have advanced to the phase III stage of drug development or received license for use, suggesting promising signals for efficacy and potentially acceptable safety and tolerability for JPsA. Further translational research in JPsA is required to improve our understanding of the impact of age at onset on treatment efficacy, as well as to provide opportunities for better management of refractory disease and improved long-term outcomes in JPsA, for ultimate patient benefit.

The epidemiology of pediatric psoriasis: A nationwide cohort study in Taiwan

Psoriasis can affect individuals of all age groups. While the epidemiology of psoriasis in adults has been extensively studied, there is limited research specifically investigating pediatric cases. This study aimed to investigate the prevalence and incidence of skin psoriasis (PsO) and psoriatic arthritis (PsA) among pediatric patients in Taiwan. A nationwide cohort of 17 535 patients with psoriatic diseases under the age of 18 was enrolled from the National Health Insurance Research Database for the period 2000-2013, including 16 129 PsO patients and 2022 PsA patients. The age- and sex-standardized prevalence and incidence of pediatric PsO and PsA were calculated. The 2007 yearly reports of age- and sex-specific distribution of the general population was adopted as a standard. The results showed that between 2000 and 2013, the prevalence for pediatric PsO increased from 0.03% to 0.07%, and from 0.003% to 0.014% for pediatric PsA. During the same period, the incidence slightly decreased from 19.81 to 17.55 per 100 000 for pediatric PsO but increased from 1.02 to 5.06 per 100 000 for pediatric PsA. Adolescents (12 to <18 years) had higher prevalence and incidence rates of PsO and PsA than children (aged ≤ 12 years), with no sex difference observed in either age group. PsA preceding PsO was more common among children than adolescents (27.07% vs. 13.46%). This study provides important insights into the prevalence and incidence of psoriatic diseases in the pediatric population. Further research is needed to identify risk factors for pediatric psoriasis and to investigate its long-term health outcomes.

Juvenile idiopathic arthritis in the young adult. Methodology, objectives, and initial data from the JUVENSER registry

OBJECTIVES

To describe the methodology, objectives, and initial data of the registry of young adult patients diagnosed with Juvenile Idiopathic Arthritis (JIA), JUVENSER. The main objective of the project is to know the sociodemographic and clinical characteristics, and disease activity of patients with JIA reaching the transition to adulthood.

MATERIAL AND METHOD

Longitudinal, prospective, multicentre study, including patients between 16 and 25 years old, with a diagnosis of JIA in any of its categories. The main objective is to determine the characteristics and activity of JIA in the young adult. It includes sociodemographic variables, clinical variables, disease activity and joint damage rates, data on the use of health resources, and treatments used. The total duration of the project will be 3 years. A cohort of 534 young adult patients was obtained.

CONCLUSIONS

The JUVENSER registry will constitute a cohort of young adults with JIA, which will allow the evaluation of the clinical characteristics and response to treatment of patients with disease onset in childhood, moving to adult clinics.

Arthritis remission with partial cartilage restoration in a 9-year-old female with hip chondrolysis following treatment with adalimumab

Hip chondrolysis is observed primarily or secondary to other diseases and is a rare but yet debilitating disease, characterised by loss of cartilage of the femoral epiphysis and significant restriction of motion. We present the case of a 9-year-old female diagnosed with hip chondrolysis associated with probable juvenile psoriatic arthritis. Avoidance of weight-bearing activities and treatment with corticosteroids, methotrexate, and adalimumab followed by aquatic therapy resulted in clinical and radiographic improvement as well as partial cartilage regeneration.

Juvenile Psoriatic Arthritis: Myth or Reality? An Unending Debate

Juvenile psoriatic arthritis (JPsA) accounts for 1-7% of all cases of juvenile idiopathic arthritis (JIA) and its definition has been a matter of controversy among pediatric rheumatologists for many years. The traditional attribution of JPsA to the spondyloarthropathy group was challenged in the early 1990s, whereas the recent demonstrations of its heterogenous nature have led to questions about its identification as a distinct category in JIA classification. It has been shown that children with the phenotype of JPsA can be divided in two subgroups, one presenting with the features of early-onset ANA-positive JIA, and another that belongs to the spectrum of spondyloarthropathies. The few studies that have compared the clinical characteristics and genetic determinants of JPsA with those of the other JIA categories have obtained contrasting findings. The debate on the categorization of JPsA as a distinct entity within JIA classification is still ongoing and has prompted the revision of its current classification.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is an umbrella term for arthritis of unknown origin, lasting for >6 weeks with onset before 16 years of age. JIA is the most common chronic inflammatory rheumatic condition of childhood. According to the International League Against Rheumatism (ILAR) classification, seven mutually exclusive categories of JIA exist based on disease manifestations during the first 6 months of disease. Although the ILAR classification has been useful to foster research, it has been criticized mainly as it does not distinguish those forms of chronic arthritis observed in adults and in children from those that may be unique to childhood. Hence, efforts to provide a new evidence-based classification are ongoing. Similar to arthritis observed in adults, pathogenesis involves autoimmune and autoinflammatory mechanisms. The field has witnessed a remarkable improvement in therapeutic possibilities of JIA owing to the availability of new potent drugs and the possibility to perform controlled trials with support from legislative interventions and large networks availability. The goal of drug therapy in JIA is to rapidly reduce disease activity to inactive disease or clinical remission, minimize drug side effects and achieve a quality of life comparable to that of healthy peers. As JIA can influence all aspects of a child's and their family's life, researchers increasingly recognize improvement of health-related quality of life as a key treatment goal.

Occurrence and risk factors of uveitis in juvenile psoriatic arthritis: Data from a population-based nationwide study in Germany

OBJECTIVE

Data on uveitis in juvenile psoriatic arthritis (JPsA), a category of juvenile idiopathic arthritis (JIA), are scarce. We describe prevalence and risk factors for JPsA-associated uveitis (JPsA-U).

METHODS

Cross-sectional data from the National Pediatric Rheumatological Database (from 2002 to 2014) were used to characterize JPsA-U and assess risk factors for uveitis development.

RESULTS

Uveitis developed in 6.6% of 1862 JPsA patients. JPsA-U patients were more frequently female (73.0 vs 62.9%, p=0.031), ANA positive (60.3 vs 37.0%, p<0.001), younger at JPsA onset (5.3 ± 4.1 vs 9.3 ± 4.4 years, p<0.001), and received DMARD (disease modifying antirheumatic drug) treatment significantly more frequently than JPsA patients without uveitis. On multivariable analysis of a subgroup of 655 patients, mean cJADAS during study documentation was significantly associated with uveitis development. Children with early onset of JPsA were significantly more frequently ANA positive (48.4% vs 35.7% for those younger than 5 years at JPsA onset versus those aged 5 years and older, p<0.001), less often affected by skin disease (55.3% vs 61.0%, p=0.032), but more frequently by uveitis (17.3% vs 3.8%, p<0.001), and required DMARD treatment more frequently (52.9% vs 43.8%, p<0.001).

CONCLUSION

The characteristics of JPsA patients developing uveitis are similar to those of patients with uveitis in other JIA categories, such as oligoarticular JIA. Especially those children with early onset of JPsA seem to be at a higher risk for ocular involvement. Our data support the notion of a major clinical difference between those patients with early versus late onset of JPsA.

New Insights on Juvenile Psoriatic Arthritis

Juvenile psoriatic arthritis (JPsA) is a relatively rare condition in childhood as it represents approximately 5% of the whole Juvenile Idiopathic Arthritis (JIA) population. According to International League of Associations of Rheumatology (ILAR) classification, JPsA is defined by the association of arthritis and psoriasis or, in the absence of typical psoriatic lesions, with at least two of the following: dactylitis, nail pitting, onycholysis or family history of psoriasis in a first-degree relative. However, recent studies have shown that this classification system could conceal more homogeneous subgroups of patients differing by age of onset, clinical characteristics and prognosis. Little is known about genetic factors and pathogenetic mechanisms which distinguish JPsA from other JIA subtypes or from isolated psoriasis without joint involvement, especially in the pediatric population. Specific clinical trials testing the efficacy of biological agents are lacking for JPsA, while in recent years novel therapeutic agents are emerging in adults. In this review, we summarize the clinical features and the current evidence on pathogenesis and therapeutic options for JPsA in order to provide a comprehensive overview on the clinical management of this complex and overlapping entity in childhood.

Psoriatic arthritis

Psoriatic arthritis (PsA) is a complex inflammatory disease with heterogeneous clinical features, which complicates psoriasis in 30% of patients. There are no diagnostic criteria or tests available. Diagnosis is most commonly made by identifying inflammatory musculoskeletal features in joints, entheses or the spine in the presence of skin and/or nail psoriasis and in the usual absence of rheumatoid factor and anti-cyclic citrullinated peptide. The evolution of psoriasis to PsA may occur in stages, although the mechanisms are unclear. In many patients, there may be little or no relationship between severity of musculoskeletal inflammation and severity of skin or nail psoriasis. The reason for this disease heterogeneity may be explained by differences in genotype, especially in the HLA region. New targeted therapies for PsA have been approved with additional therapies in development. These developments have substantially improved both short-term and long-term outcomes including a reduction in musculoskeletal and skin manifestations and in radiographic damage. With efforts underway aimed at improving our understanding of the molecular basis for the heterogeneity of PsA, a personalized approach to treating PsA may become possible.

Biological classification of childhood arthritis: roadmap to a molecular nomenclature

Chronic inflammatory arthritis in childhood is heterogeneous in presentation and course. Most forms exhibit clinical and genetic similarity to arthritis of adult onset, although at least one phenotype might be restricted to children. Nevertheless, paediatric and adult rheumatologists have historically addressed disease classification separately, yielding a juvenile idiopathic arthritis (JIA) nomenclature that exhibits no terminological overlap with adult-onset arthritis. Accumulating clinical, genetic and mechanistic data reveal the critical limitations of this strategy, necessitating a new approach to defining biological categories within JIA. In this Review, we provide an overview of the current evidence for biological subgroups of arthritis in children, delineate forms that seem contiguous with adult-onset arthritis, and consider integrative genetic and bioinformatic strategies to identify discrete entities within inflammatory arthritis across all ages.

Pediatric psoriatic arthritis: a population-based cohort study of risk factors for onset and subsequent risk of inflammatory comorbidities

Background

Relatively little is known about the epidemiology of juvenile psoriatic arthritis (PsA), including clinical features associated with the development of arthritis among children with psoriasis and subsequent risk of inflammatory comorbidities.

Objective

To identify the overall risk of arthritis among children with psoriasis and subsequent risk of inflammatory comorbidities.

Methods

Using Clinformatics™ DataMart (OptumInsight, Eden Prairie, MN) de-identified US administrative claims data from 2000-2013, we identified children 0-16 years with an incident diagnosis of psoriasis or PsA using ICD-9-CM diagnostic, procedure and pharmacy billing codes. Cox proportional hazard regression was performed to assess clinical features associated with development of arthritis in children with psoriasis. Incidence rate ratios were used to compare the relative frequency of co-morbid diagnoses.

Results

We identified 212 children with PsA, 4,312 with psoriasis-only, and 45,240 controls. Approximately 33% of children with PsA received a diagnostic code for psoriasis before arthritis. Median time to index code for arthritis after index code for psoriasis was 17.6 months (IQR 4.1-38.1). Older age and uveitis were associated with a significantly increased risk of developing arthritis in children with psoriasis. Children with PsA had a significantly increased risk of uveitis, diabetes, and depressive disorder when compared to patients with psoriasis and inflammatory bowel disease, uveitis, diabetes, and depressive disorder when compared to controls.

Conclusion

Most children with PsA developed arthritis first. Older age and uveitis were risk factors for arthritis among children with psoriasis. PsA was associated with increased risk of several clinically relevant inflammatory comorbidities.

Psoriasis and associated variables in classification and outcome of juvenile idiopathic arthritis - an eight-year follow-up study

BACKGROUND

To study the impact of psoriasis and features associated with psoriasis on classification and outcome in a population-based follow-up cohort of children with juvenile idiopathic arthritis (JIA).

METHODS

In all, 440 children with JIA were followed for a median of 8 years in a prospective Nordic population-based cohort study. Data for remission was available for 427 of these children. The presence of psoriasis, psoriasis-like rash, dactylitis, nail pitting, enthesitis, tenosynovitis and heredity was assessed in relation to ILAR classification and remission.

RESULTS

Clinical findings associated with psoriasis developed consecutively during the 8-year period. Six of 14 children with psoriasis were not classified as juvenile psoriatic arthritis according to the ILAR criteria at 8 year follow-up. Dactylitis was more common in children with early onset of JIA. After 8 years we found a cumulative median number of eleven arthritic joints in children with psoriasis or psoriasis-like rash compared with six in the rest of the cohort (p = 0.02). Also, the chance for not being in remission after 8 years increased significantly in patients with psoriasis, psoriasis-like rash or at least two of: 1) first-degree heredity for psoriasis or psoriatic arthritis, 2) dactylitis or 3) nail pitting, compared with the rest of the group (OR 3.32, p = 0.010).

CONCLUSIONS

Our results indicate a more severe disease over time in psoriasis-associated JIA, as features of psoriasis develop during the disease course. This group is a major challenge to encompass in a future JIA classification in order to facilitate early tailored treatment.

A better understanding of juvenile idiopathic arthritis with classification criteria

Juvenile idiopathic arthritis, JIA, is a novel rheumatic disease in childhood introduced by the International League of Associations for Rheumatology. It is defined as a chronic, inflammatory disorder of unknown etiology, which is classified into seven categories; systemic-onset type, persistent and extended oligoarthritis, polyarthritis with rheumatoid factor negative, polyarthritis with rheumatoid factor positive, psoriatic arthritis, enthesitis-related arthritis and undifferentiated arthritis. As each category of JIA has different features in clinical phenotypes, precise subtyping is required for research and management. However, some modifications to the criteria might be helpful for getting better answers in diagnosis because of ethnical difference in prevalence and subtype distribution. Actually in Japanese population, a unique subset "B27-negative polyenthesitis" termed by Shichikawa should be included in enthesitis-related arthritis of JIA as a different type of enthesitis from B27-positive counterpart of spondyloarthritis in adulthood. Deep insights into the classification criteria will be needed for the better understanding of JIA.

Obesity and Pediatric Psoriatic Arthritis

Objective

Studies in adults have shown a significant association between obesity and psoriatic arthritis, however the association of obesity with pediatric psoriatic arthritis is unknown. We aimed to evaluate obesity in pediatric psoriatic arthritis.

Methods

We conducted a cross-sectional study of children with psoriasis and psoriatic arthritis evaluated at a single center between 6/2010 and 9/2014. Two healthy reference populations were utilized: 1) local reference population from the surrounding community and 2) a national reference population derived from NHANES. Age and sex-specific z-scores for weight, height, and body mass index (BMI) were calculated. Differences in clinical and demographic characteristics between groups were assessed.

Results

During the study period, 48 children with psoriatic arthritis and 231 patients with psoriasis were evaluated. Three (6.2%) and 5 (10.4%) of the children with psoriatic arthritis were overweight or obese, respectively. In comparison to the reference healthy groups and psoriasis patients, the mean BMI z-score of children with psoriatic arthritis was not statistically different. However, patients with psoriasis were more likely to be obese than the community reference population (p-value <0.001).

Conclusions

Children with psoriasis were more obese than the healthy reference population, however there was no statistically significant difference in obesity between children with psoriatic arthritis and psoriasis or psoriatic arthritis and the reference population. This lack of association may be reflective of true differences in pediatric and adult-onset disease and warrants further investigation.

A Family History of Psoriasis in a First-degree Relative in Children with JIA: to Include or Exclude?

OBJECTIVE

To determine the consequences of disregarding first-degree relatives with psoriasis (FRP) as a classification criterion in juvenile idiopathic arthritis (JIA).

METHODS

Criteria were examined in children from a prospective cohort with unclassified and psoriatic JIA.

RESULTS

FRP was the most common reason children were unclassified (57/85, 67%); all 57 children could be classified if FRP were disregarded as an exclusion criterion. FRP was a necessary inclusion criterion to classify 11/77 (14.3%) children with psoriatic JIA.

CONCLUSION

Eliminating FRP as an exclusion criterion, but keeping it as an inclusion criterion in psoriatic JIA simplifies classification, though it is unclear whether the resulting classification would be better.

Psoriasis: Epidemiology, clinical features, co-morbidities, and clinical scoring

On the basis of current evidence derived from hospital-based studies, mostly from North India, the prevalence of psoriasis in adults varies from 0.44 to 2.8%, with a much lower prevalence in children. The peak age at onset in adults is in the third and fourth decade of life, with a slight male preponderance. It is recommended that population-based large epidemiologic studies should be undertaken in different parts of the country for estimating the correct prevalence of psoriasis in general population. Chronic plaque-type psoriasis is the most common morphologic presentation of psoriasis, accounting for more than 90% of all cases. Other morphologic variants that deserve special mention include palmoplantar psoriasis, pustular psoriasis, and recalcitrant psoriasis. For epidemiologic purposes, psoriasis can be classified into early and late onset psoriasis. Psoriasis can be classified on the basis of morphology and extent of involvement into localized and widespread disease. For the purpose of clinical trials, psoriasis may be classified as mild psoriasis, moderate psoriasis, and severe psoriasis. The literature shows that there is a significant risk of psoriatic arthritis (7-48%) in patients with plaque-type psoriasis. Hence, it is recommended to evaluate for its presence by detailed history taking and clinical examination, and if necessary, by appropriate radiological investigations. Evidence on the association between plaque-type psoriasis and cardiovascular disease risk factors and ischemic heart disease isinconsistent. On the basis ofavailable evidence, it is prudent to proactively look for metabolic syndrome, dyslipidemia, and obesity, especially in patientswith severe psoriasis (Level 1+ evidence based on systematic reviews and meta-analysis). Based on the current evidence, the psoriasis area severity index appears to be the most valid and reproducible clinical severity score in the management of adult patients with plaque-type psoriasis.

The Epidemiology of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic systemic inflammatory disorder characterized by joint and entheseal inflammation with a prevalence of 0.05% to 0.25% of the population and 6% to 41% of patients with psoriasis. PsA is a highly heterogeneous inflammatory arthritis. In this review, current knowledge is discussed regarding the epidemiology of PsA, including disease manifestations, classification criteria for adult and juvenile PsA, methods for recognizing early PsA, including use of screening tools and knowledge of risk factors for PsA, and medical comorbidities associated with PsA.

Enthesitis as a component of dactylitis in psoriatic juvenile idiopathic arthritis: histology of an established clinical entity

CONTEXT

Imaging of dactylitis in adult psoriatic arthritis suggests a pathophysiological role for enthesitis. However, histological definition of the dactylitic digit is unavailable.

OBJECTIVE

We evaluated the role of enthesitis in dactylitis associated with psoriatic juvenile idiopathic arthritis (psJIA) in a child who underwent detailed imaging and histologic evaluation.

DESIGN

Radiographs, ultrasound and high-resolution magnetic resonance imaging were employed to define the locus of disease in two dactylitic digits from a 14-year-old girl with psJIA. Biopsies were stained with hematoxylin and eosin, CD3, CD20, CD4, CD8 and CD117 and examined via light microscopy.

RESULTS

Radiologic features of dactylitis included enhanced signal at digital entheses without accompanying synovitis or tenosynovitis. Histologically, finger and toe tissue exhibited hypervascular tenosynovium with a fibromyxoid expansion of fibrous tissue. This was accompanied by sparse to moderate perivascular lymphocytic inflammation consisting predominantly of T cells, with occasional admixed B cells and mast cells. Neutrophils and plasma cells were absent. Fibrocartilage exhibited reactive features including increased extracellular myxoid matrix, binucleation, and focal necrosis, without cellular inflammation. Fibrinous synovitis and mild reactive synoviocyte hyperplasia were seen.

CONCLUSIONS

Dactylitis in psJIA bears a radiographic resemblance to the condition in adult psoriatic arthritis. Histologic hallmarks include an expanded mast cell-populated extracellular myxoid matrix, cartilage degeneration, and a T cell-rich perivascular inflammatory infiltrate. These findings help to define enthesitis as a clinicopathologic entity.

Disease of the year: juvenile idiopathic arthritis-associated uveitis--classification and diagnostic approach

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease and the most common systemic association of uveitis in children. JIA is subdivided into seven clinically more homogeneous subtypes, using the International League of Associations for Rheumatology (ILAR) classification system: systemic arthritis, oligoarthritis, rheumatoid factor (RF)-negative polyarthritis, RF-positive polyarthritis, psoriatic arthritis, enthesitis-related arthritis, and undifferentiated arthritis. Uveitis is very rare in patients with systemic onset JIA and in patients with juvenile-onset rheumatoid arthritis. Patients with early-onset antinuclear antibody (ANA)-positive oligoarticular JIA have the highest risk of developing chronic iridocyclitis. Ocular involvement in enthesitis-related arthritis is characterized by recurrent acute symptomatic iridocyclitis. The diagnosis and differential diagnosis of JIA are based on history, physical examination, and laboratory investigations, including complete blood count, acute-phase reactants, ANA, RF, HLA-B27, and musculoskeletal imaging studies. Recent studies have revealed distinct gene expression profiles that may be useful in the diagnosis, classification, and follow-up of JIA patients.

Juvenile Psoriatic Arthritis (JPsA): juvenile arthritis with psoriasis?

BACKGROUND

Following the introduction of the ILAR criteria for juvenile idiopathic arthritis, juvenile psoriatic arthritis (JPsA) has become a better recognized category within the inflammatory arthritides of childhood. There are fewer reports describing the characteristics and long-term outcome of patients with JPsA than other subtypes of JIA.The aim of our study was to determine the long-term outcome and clinical course of patients with juvenile psoriatic arthritis (JPsA) and to define subgroups of JPsA.

METHODS

Clinical records of all patients meeting criteria for JPsA were reviewed and divided into 4 groups depending on their clinical features and onset type. Patient characteristics and clinical features at onset and during follow-up were determined.

RESULTS

The cohort consisted of 119 patients: 65 with oligoarticular-onset (55%; persistent 44 and extended 21), 34 (29%) with RF(-) and 4 (3%) RF(+) polyarticular and 16 (13%) enthesitis-related arthritis (ERA). At diagnosis patients with ERA were oldest and more commonly male (p=0.001 and =0.01 respectively). Patients with a polyarticular course had more involvement of small joints of the hands and wrist when compared to patients with persistent oligoarticular and ERA (p<0.001) while patients with ERA had more hip and sacroiliac arthritis (p<0.001 for both). Nail changes were seen in 66 patients (57%) and were associated with DIP involvement (p=0.0034).

OUTCOME

Time to first inactive disease on, but not off, therapy was significantly longer among patients with polyarticular course when compared to oligoarticular and ERA (p=0.016 and p=0.48 respectively). Patients with polyarticular course more frequently had contractures during follow-up than other groups (p=0.01).

CONCLUSION

The long-term outcome of with JPsA was generally good. Patients with JPsA did not appear to form distinct sub-group of patients but rather resembled JIA patients with onset types without psoriasis.

Multiple juvenile idiopathic arthritis subtypes demonstrate proinflammatory IgG glycosylation

OBJECTIVE

Rheumatoid arthritis is associated with an excess of agalactosylated (G0) IgG that is considered relatively proinflammatory. Assessment of this association in juvenile idiopathic arthritis (JIA) is complicated by age-dependent IgG glycan variation. The aim of this study was to conduct the first large-scale survey of IgG glycans in healthy children and patients with JIA, with a focus on early childhood, the time of peak JIA incidence.

METHODS

IgG glycans from healthy children and disease-modifying antirheumatic drug-naive patients with JIA were characterized using high-performance liquid chromatography. Agalactosylated glycans were quantitated with reference to monogalactosylated (G1) species. Associations were sought between the G0:G1 ratio and disease characteristics.

RESULTS

Among healthy children ages 9 months to 16 years (n = 165), the G0:G1 ratio was highly age dependent, with the ratio peaking to 1.19 in children younger than age 3 years and declining to a nadir of 0.83 after age 10 years (Spearman's ρ = 0.60, P < 0.0001). In patients with JIA (n = 141), the G0:G1 ratio was elevated compared with that in control subjects (1.32 versus 1.02; P < 0.0001). The G0:G1 ratio corrected for age was abnormally high in all JIA subtypes (enthesitis-related arthritis was not assessed), most strikingly in systemic JIA. Glycosylation aberrancy was comparable in patients with and those without antinuclear antibodies and in both early- and late-onset disease and exhibited at most a weak correlation with markers of inflammation.

CONCLUSION

IgG glycosylation is skewed toward proinflammatory G0 variants in healthy children, in particular during the first few years of life. This deviation is exaggerated in patients with JIA. The role for IgG glycan variation in immune function in children, including the predilection of JIA for early childhood, remains to be defined.

It is time to rethink juvenile idiopathic arthritis classification and nomenclature

Juvenile idiopathic arthritis (JIA) is not a disease, but an exclusion diagnosis that encompasses all forms of arthritis that begin before the age of 16 years, persist for more than 6 weeks, and are of unknown origin. This heterogeneous group of chronic arthritides has been classified on clinical and laboratory grounds to try to identify homogeneous, mutually exclusives categories suitable for etiopathogenic studies . Recent advances have shown that while some JIA categories identify quite definite disease entities, others still include heterogeneous conditions. Some aspects of JIA classification and nomenclature need therefore to be reconsidered.

Current medical treatments for juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) differs markedly from adult rheumatoid arthritis. It is not a single disease, but an exclusion diagnosis that gather together all forms of arthritis that begin before the age of 16 years, persist for more than 6 weeks, and are of unknown origin. The advent of the new biological treatments has dramatically changed both the observed responses to treatment and the expectations of therapies. The implementation of an adequate legislation as well as the presence of international research networks of pediatric rheumatology have contributed to foster the conduct of controlled clinical trials and the development of validated outcome measures. This review will currently describe the methodological approach for performing clinical trials in JIA as well as the current available drug treatment.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis is a heterogeneous group of diseases characterised by arthritis of unknown origin with onset before age of 16 years. Pivotal studies in the past 5 years have led to substantial progress in various areas, ranging from disease classification to new treatments. Gene expression profiling studies have identified different immune mechanisms in distinct subtypes of the disease, and can help to redefine disease classification criteria. Moreover, immunological studies have shown that systemic juvenile idiopathic arthritis is an acquired autoinflammatory disease, and have led to successful studies of both interleukin-1 and interleukin-6 blockade. In other forms of the disease, synovial inflammation is the consequence of a disturbed balance between proinflammatory effector cells (such as T-helper-17 cells), and anti-inflammatory regulatory cells (such as FOXP3-positive regulatory T cells). Moreover, specific soluble biomarkers (S100 proteins) can guide individual treatment. Altogether these new developments in genetics, immunology, and imaging are instrumental to better define, classify, and treat patients with juvenile idiopathic arthritis.

Classification of juvenile spondyloarthritis: Enthesitis-related arthritis and beyond

Spondyloarthritis (SpA) refers to a spectrum of immune-mediated inflammatory diseases with overlapping features, which differ from other types of inflammatory arthritis in genetic predisposition, pathogenesis and outcome. SpA frequently involves the axial skeleton, and can result in abnormal bone formation with eventual ankylosis of the spine, resulting in substantial disability. SpA often begins as an 'undifferentiated' disease, the presentation of which differs in children and adults; most notably, spinal involvement is uncommon, while hip arthritis and enthesitis are frequently seen in juvenile-onset disease. Currently, the classification of SpA in adults and children is approached differently. Using the International League of Associations for Rheumatology (ILAR) system for juvenile idiopathic arthritis, most childhood SpA is classified as enthesitis-related arthritis. However, in contrast to adult SpA classification, the presence of, or a family history of, psoriasis dictates a separate category of juvenile idiopathic arthritis. More importantly, the ILAR system does not specifically recognize the presence of axial disease in juvenile SpA. Resolution of these issues will improve communication and the transitioning of patients from pediatric to adult clinics, will facilitate research in genetics and pathogenesis, and will be particularly important in the evaluation of tumor necrosis factor inhibitors and other biologic agents for early, axial SpA.

Profile of Indian patients with juvenile onset chronic inflammatory joint disease using the ILAR classification criteria for JIA: a community-based cohort study

OBJECTIVE

To assess the current International League of Associations for Rheumatology (ILAR) classification criteria (Edmonton, 2001) for juvenile idiopathic arthritis (JIA) in Indian patients.

METHODS

Out of 441 children, 330 with chronic joint pains were diagnosed with juvenile onset chronic inflammatory arthritis and followed in an observational cohort. Our study was carried out from 1994 to 2006 in a community rheumatology clinic. Emphasis was placed on obtaining data required by the ILAR system. Of the original group, 235 children were eventually classified as having JIA; 108 were examined during the first year of illness.

RESULTS

We assigned 224 children (95%) to discrete JIA categories: enthesitis-related arthritis (ERA; 36%), oligoarthritis (OLA-persistent; 17%), polyarthritis rheumatoid factor (RF)-negative (17%), polyarthritis RF-positive (12%), systemic arthritis (8%), OLA-extended (4%), and psoriatic arthritis (1%). The remaining 11 children (5%) were classified with undifferentiated arthritis (mostly an overlap due to seropositive RF and/or HLA-B27). The prevalence of ERA (89% HLA-B27-positive) and seropositive RF was unexpectedly high. Although agreement (kappa > 0.79) with the American College of Rheumatology criteria and the European Spondylarthropathy Study Group criteria was good to excellent, the ILAR system was found to be more comprehensive and clinically homogeneous. However, some problems appear unique in our scenario.

CONCLUSION

A wide-spectrum phenotype of JIA is demonstrated by an Indian cohort. Although useful, RF and HLA-B27 in this population proved problematic to the ILAR classification.

Approach to knee effusions

The presence of an intra-articular knee effusion requires an extensive differential diagnosis and a systematic diagnostic approach. Pediatric knee effusions occur most commonly as acute hemarthroses after traumatic injury. However, the knee joint is susceptible to effusions secondary to a wide variety of atraumatic causes. Special attention is required in the atraumatic effusion to distinguish features of infectious, postinfectious, rheumatologic, hematologic, vasculitic, and malignant disease. This review discusses the various etiologies of both traumatic and atraumatic pediatric knee effusions highlighting the historical, physical examination, and laboratory characteristics to aid the emergency provider in diagnosis and initial management.

Oligoarticular and polyarticular JIA: epidemiology and pathogenesis

Juvenile idiopathic arthritis (JIA) refers to a group of chronic childhood arthropathies of unknown etiology, currently classified into subtypes primarily on the basis of clinical features. Research has focused on the hypothesis that these subtypes arise through distinct etiologic pathways. In this Review, we discuss four subtypes of JIA: persistent oligoarticular, extended oligoarticular, rheumatoid-factor-positive polyarticular and rheumatoid-factor-negative polyarticular. These subtypes differ in prevalence between ethnic groups and are associated with different HLA alleles. Non-HLA genetic risk factors have also been identified, some of which reveal further molecular differences between these subtypes, while others suggest mechanistic overlap. Investigations of immunophenotypes also provide insights into subtype differences: adaptive immunity seems to have a prominent role in both polyarticular and oligoarticular JIA, and the more-limited arthritis observed in persistent oligoarticular JIA as compared with extended oligoarticular JIA may reflect more-potent immunoregulatory T-cell activity in the former. Tumor necrosis factor seems to be a key mediator of both polyarticular and oligoarticular JIA, especially in the extended oligoarticular subtype, although elevated levels of other cytokines are also observed. Limited data on monocytes, dendritic cells, B cells, natural killer T cells and neutrophils suggest that the contributions of these cells differ across subtypes of JIA. Within each subtype, however, common pathways seem to drive joint damage.

Comparison of patients with juvenile psoriatic arthritis and nonpsoriatic juvenile idiopathic arthritis: how different are they?

OBJECTIVE

To compare the clinical features and outcome between patients with juvenile psoriatic arthritis (JPsA) and non-JPsA juvenile idiopathic arthritis (JIA).

METHODS

Fifty-three children with JPsA, 32 with < 5 joints in the first 6 months of disease (oligo-JPsA) and 21 (> or = 5 joints) polyarticular-onset (poly-JPsA) were compared to 53 patients with JIA who were matched by sex, age, date of diagnosis, and articular onset pattern.

RESULTS

There was no difference in the percentage of patients between the oligoarticular groups who developed extended oligoarthritis or in the percentage of patients who were positive for antinuclear antibodies. The only differences were that 25% of patients with oligo-JPsA had dactylitis compared to 0% of patients with oligo-JIA (p < 0.01) and 50% had nail pitting as compared to 18.7% (p < 0.05). In polyarticular patients the percentages with dactylitis were similar (19% vs 38%; p = 0.25). The frequency of uveitis was identical in the oligoarticular patients but a higher rate was seen in poly-JPsA compared to poly-JIA (23.8% vs 0%; p = 0.02), while contractures were more frequent in poly-JIA compared to poly-JPsA during the course of the illness (47.6% vs 14.3%; p = 0.03) but not at last followup (14.3% vs 4.7%; p = 0.6). At last followup the mean Childhood Health Assessment Questionnaire scores were similar in both the polyarticular and oligoarticular groups.

CONCLUSION

There were only a few differences between patients with JPsA and JIA regarding disease onset, disease course, and outcome. We suggest that large, longterm prospective studies are required to accurately determine whether subdividing JIA according to psoriasis is worthwhile.

Management of childhood psoriasis

Treating children with psoriasis represents one of the most rewarding yet constantly challenging endeavors in dermatology. These patients require time, energy, enthusiasm, empathy, and current, comprehensive knowledge of the unique clinical presentations in children and available therapies, including clinical action spectrum, mechanism of action, potential toxicity, and monitoring. Longitudinal trials examining the epidemiology and natural history of psoriasis, as well as the safety and efficacy of current and emerging treatments, are desperately needed in the pediatric population. Partner with the patient, family, and other multidisciplinary providers to form an educational and therapeutic alliance. Early in the course of disease, schedule frequent visits for reinforcement of the therapeutic plan, education, clinical and treatment monitoring, and support. As the disease and the patient's physical, psychosocial and emotional level of functioning evolve, so too will the requirement for follow-up and monitoring. Patient advocacy and education groups, such as the National Psoriasis Foundation (www.psoriasis.org; 800-723-9166) are excellent resources and can serve as an extension of your comprehensive care.

Juvenile psoriatic arthritis: longterm outcome and differentiation from other subtypes of juvenile idiopathic arthritis

OBJECTIVE

To compare outcomes in patients with juvenile psoriatic arthritis (PsA) with those in patients with other juvenile idiopathic arthritis (JIA) subtypes, and to evaluate characteristics and genetic markers that may differentiate PsA from other subtypes of JIA.

METHODS

JIA patients first admitted between 1980 and 1985 were clinically examined after a median of 15 years. Health status was reassessed by the Short Form-36 Health Survey (SF-36) after a median of 23 years. Of 336 JIA patients, 31 (9%) had PsA.

RESULTS

Predictors of PsA were psoriasis in the patient (OR 12.06, p = 0.004) or first-degree relative (OR 30.86, p < 0.001), dactylitis (OR 10.97, p < 0.001), and ankle/toe arthritis (OR 3.04, p = 0.038) within the first 6 months. HLA-DRB1*11/12 status (OR 2.69, p = 0.040) and onset after age 6 years (OR 4.41, p = 0.004) differentiated PsA from either oligoarthritis or polyarthritis. After 15 years, PsA patients had poorer physical health than healthy population controls (p = 0.001). After 23 years, the SF-36 physical scores were poorer in PsA patients than in those with either oligoarthritis or polyarthritis (p < 0.045). The need for disease-modifying antirheumatic drugs and/or anti-tumor necrosis factor agents was present in 33% of PsA versus 8% in oligoarthritis and 13% in either oligoarthritis or polyarthritis patients (p < 0.001 and p = 0.002, respectively).

CONCLUSION

In addition to a history of psoriasis, dactylitis, ankle or toe arthritis, and DRB1*11/12 in children with JIA indicate the likelihood of PsA, a subtype associated with unfavorable outcome.