Prediction of methotrexate efficacy and adverse events in patients with juvenile idiopathic arthritis: a systematic literature review

Clinical and laboratory features of juvenile idiopathic arthritis with wrist involvement: Results of a retrospective cohort study

BACKGROUND

Previous studies in the pre-biological era showed an association of wrist inflammation in juvenile idiopathic arthritis (JIA) with progressive disease course, polyarticular involvement and failure of methotrexate treatment.

AIM

To describe features of JIA, associated with wrist arthritis.

METHODS

Data from about 753 JIA patients were included in this retrospective cohort study. The clinical and laboratory features of patients with and without wrist involvement were analyzed.

RESULTS

Wrist involvement was found in oligoarthritis (5.8%), RF(-)/RF(+) polyarthritis (44.9%/15.0%), enthesitis-related arthritis (17.7%), and systemic (58.6%) JIA categories. Unilateral wrist involvement was typical for oligoarthritis patients, bilateral involvement was either equal to that of unilateral involvement or was more frequent in other categories. Wrist arthritis was found to be associated with female sex, a low incidence of uveitis, and more indications of systemic inflammation, including elevated levels of C-reactive protein, erythrocyte sedimentation rate, and platelets, as well as involvement of the cervical spine, temporomandibular, shoulder, elbow, metacarpophalangeal, proximal interphalangeal, distal interphalangeal, hip, ankle, and tarsus arthritis. The number of patients with hip osteoarthritis and hip replacement was also higher. Wrist arthritis was associated with a lower probability of achieving remission [hazard ratio (HR) = 1.3 (95%CI: 1.0-1.7), P = 0.055], and a higher probability of being treated with biologics [HR = 1.7 (95%CI: 1.3-2.10, P = 0.00009)].

CONCLUSION

Wrist arthritis in JIA patients is a marker of a severe disease course, characterized by more intensive inflammation, unfavorable outcomes, and. requiring more intensive treatment with early administration of biologics. Close monitoring of wrist inflammation with ultrasound and MR assessment with early biological treatment might improve the outcomes.

Methotrexate Intolerance in Juvenile Idiopathic Arthritis: Definition, Risks, and Management

Juvenile idiopathic arthritis is the most common rheumatic disorder in childhood and adolescence posing a significant threat of short-term and long-term disability if left untreated. Methotrexate is a folic acid analog with various immunomodulatory properties. It has demonstrated significant efficacy for the treatment of juvenile idiopathic arthritis, often considered the preferred first-line disease-modifying anti-rheumatic drug given as monotherapy or in combination with biological drugs. Despite this, there is a considerable risk for treatment disruptions owing to the high prevalence of methotrexate intolerance, with symptoms such as nausea, stomach ache, vomiting, and behavioral symptoms. Many different risk factors for the intolerance have been proposed including gender, age, disease activity, treatment duration, dosing and administration, and genetic and psychological factors. As the studies have shown contradictory results, many questions are left unanswered. Therefore, a consensus regarding outcome measures and reporting is crucial. In this review, we describe the identification and assessment of methotrexate intolerance and evaluate potential risk factors, genetic associations as well as management strategies.

Glutathione S-Transferase Gene Polymorphisms as Predictors of Methotrexate Efficacy in Juvenile Idiopathic Arthritis

Because of the unpredictable efficacy of methotrexate (MTX) in the treatment of juvenile idiopathic arthritis (JIA), the possibility of a favourable outcome is reduced in more than 30% of patients. To investigate the possible influence of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) gene deletion polymorphisms on MTX efficacy in patients with JIA, we determined these polymorphisms in 63 patients with JIA who did not achieve remission and 46 patients with JIA who achieved remission during MTX therapy. No significant differences were observed in the distribution of single GSTM1 or GSTT1 deletion polymorphisms or their combination between the two groups: 58.7% to 63.5%; p = 0.567, 17.4% to 22.2%; p = 0.502, and 13% to 12.7%; p = 0.966, respectively. Our results suggest that GSTM1 and GSTT1 deletion polymorphisms do not influence the efficacy of MTX in patients with JIA. Additional studies are required to determine the possible influence of GST deletion polymorphisms on MTX efficacy in patients with JIA.

Factors determining resistance to conventional disease-modifying anti-rheumatic drug treatment in oligoarticular juvenile idiopathic arthritis

OBJECTIVE

Our study was designed to investigate the reasons for starting the conventional disease-modifying anti-rheumatic drugs (DMARDs) and the variables that impact the response to DMARD treatment in oligoarticular juvenile idiopathic arthritis (JIA) patients.

METHODS

Oligoarticular JIA patients (n = 187) were categorized into two groups: Group A consisted of patients who achieved remission with DMARD, and Group B comprised those who did not respond to DMARD therapy.

RESULTS

DMARDs were initiated for various reasons: 68 (36.4%) due to active disease despite nonsteroidal anti-inflammatory drugs (± intra-articular corticosteroid) treatment, 59 (31.6%) due to uveitis, 49 (26.2%) due to extended oligoarticular JIA, and 11 (5.9%) due to inflammatory bowel disease. One hundred twenty-three patients (65.8%) achieved remission with DMARDs (Group A), while 64 patients (34.2%) did not respond to DMARD therapy (Group B). In Group B, patients had higher C-reactive protein (CRP) levels as well as higher Juvenile Idiopathic Arthritis Disease Activity Scores-71 (JADAS-71) at diagnosis (both p < 0.001). Moreover, extended oligoarticular JIA subtype (p = 0.017) and involvement of small joints at diagnosis (p = 0.043) were more prevalent among these patients. Group A exhibited a higher frequency of antinuclear antibody positivity (p = 0.014). Elevated CRP levels (> 1.1 mg/dL) (OR 1.308, 95% CI 1.203-3.574; p < 0.001) and high JADAS-71 at diagnosis (> 15.8) (OR 1.659, 95% CI 1.179-2.941; p < 0.001) were associated with DMARD resistance.

CONCLUSION

Elevated CRP and high JADAS-71 at diagnosis were the main factors associated with DMARD resistance in oligoarticular JIA. Prospective long-term studies may help verify the role of these factors associated with DMARD resistance in oligoarticular JIA. Key Points • Conventional DMARDs were most commonly started due to active disease despite NSAID (± intra-articular corticosteroids). • Remission was achieved with DMARD in 65.8% of oligoarticular JIA patients. • Elevated CRP and high JADAS-71 at diagnosis were associated with DMARD resistance.

Towards stratified treatment of JIA: machine learning identifies subtypes in response to methotrexate from four UK cohorts

BACKGROUND

Methotrexate (MTX) is the gold-standard first-line disease-modifying anti-rheumatic drug for juvenile idiopathic arthritis (JIA), despite only being either effective or tolerated in half of children and young people (CYP). To facilitate stratified treatment of early JIA, novel methods in machine learning were used to i) identify clusters with distinct disease patterns following MTX initiation; ii) predict cluster membership; and iii) compare clusters to existing treatment response measures.

METHODS

Discovery and verification cohorts included CYP who first initiated MTX before January 2018 in one of four UK multicentre prospective cohorts of JIA within the CLUSTER consortium. JADAS components (active joint count, physician (PGA) and parental (PGE) global assessments, ESR) were recorded at MTX start and over the following year. Clusters of MTX 'response' were uncovered using multivariate group-based trajectory modelling separately in discovery and verification cohorts. Clusters were compared descriptively to ACR Pedi 30/90 scores, and multivariate logistic regression models predicted cluster-group assignment.

FINDINGS

The discovery cohorts included 657 CYP and verification cohorts 1241 CYP. Six clusters were identified: Fast improvers (11%), Slow Improvers (16%), Improve-Relapse (7%), Persistent Disease (44%), Persistent PGA (8%) and Persistent PGE (13%), the latter two characterised by improvement in all features except one. Factors associated with clusters included ethnicity, ILAR category, age, PGE, and ESR scores at MTX start, with predictive model area under the curve values of 0.65-0.71. Singular ACR Pedi 30/90 scores at 6 and 12 months could not capture speeds of improvement, relapsing courses or diverging disease patterns.

INTERPRETATION

Six distinct patterns following initiation of MTX have been identified using methods in artificial intelligence. These clusters demonstrate the limitations in traditional yes/no treatment response assessment (e.g., ACRPedi30) and can form the basis of a stratified medicine programme in early JIA.

FUNDING

Medical Research Council, Versus Arthritis, Great Ormond Street Hospital Children's Charity, Olivia's Vision, and the National Institute for Health Research.

Abatacept as Monotherapy and in Combination With Methotrexate in Patients With Juvenile Idiopathic Arthritis: Analysis of 2 Phase III Trials

OBJECTIVE

To describe the efficacy and safety data of children with polyarticular-course juvenile idiopathic arthritis (pcJIA) treated with abatacept (ABA) + methotrexate (MTX) or ABA monotherapy when prior MTX use was either ineffective or not tolerated.

METHODS

Posthoc analysis of 2 phase III trials of subcutaneous (SC) and intravenous (IV) ABA over 2 years in patients with pcJIA (aged 2-17 years). Patients were stratified by treatment with ABA + MTX or ABA monotherapy and further by prior biologic use. Efficacy outcomes included JIA-American College of Rheumatology (JIA-ACR) responses, Juvenile Arthritis Disease Activity Score in 27 joints using C-reactive protein (JADAS27-CRP), and safety. Descriptive pharmacokinetic analyses were also performed.

RESULTS

Efficacy responses (JIA-ACR and JADAS27-CRP) were similar between patients receiving ABA + MTX (n = 310) or ABA monotherapy (n = 99) and persisted over 2 years. Clinical response rates were similar in biologic-naïve patients and prior biologic users; this was independent of MTX use. Across both studies, ABA + MTX and ABA monotherapy displayed similar safety profiles. Pharmacokinetic results revealed similar minimum steady-state trough ABA concentrations between studies. Further, baseline MTX did not influence ABA clearance and was not a significant predictor of JIA-ACR responses.

CONCLUSION

ABA monotherapy (SC and IV) was effective and well tolerated in children with pcJIA when prior MTX use was ineffective or not tolerated. Treatment effects of ABA appear to be independent of MTX coadministration. Consequently, ABA monotherapy can be considered for those with prior biologic therapy if MTX use is inappropriate. (ClinicalTrials.gov: NCT01844518 and NCT00095173).

Musculoskeletal Ultrasound in Childhood Arthritis Limited Examination: A Comprehensive, Reliable, Time-Efficient Assessment of Synovitis

OBJECTIVE

To develop and initially validate a comprehensive pediatric musculoskeletal ultrasound (MSUS) joint-specific scoring system, and to determine the minimum number of joints needed to identify active disease.

METHODS

A semiquantitative scoring system was developed by consensus and initially validated by interrater reliability using intraclass correlation coefficients (ICCs). Subsequently, newly diagnosed juvenile idiopathic arthritis patients with an active joint count of >4 had a 42-joint MSUS performed at baseline and 3 months using this protocol. A minimum set of joints needed to identify all patients with synovitis on MSUS was obtained through a data reduction process. Spearman's correlation (rs ) was calculated to determine the association between MSUS findings and clinical Juvenile Arthritis Disease Activity Score in 10 joints (cJADAS10). Standardized response means (SMRs) were used to assess change over time.

RESULTS

The final joint-specific scoring system revealed an excellent interrater reliability (ICC 0.81-0.96) for all joints. Thirty patients were enrolled. Scanning 5 joints bilaterally (wrists, second and third metacarpophalangeal joints, knees and ankles) captured 100% of children with B-mode synovitis and had moderate correlation with the cJADAS10 at baseline (rs  = 0.45). Mean ultrasound scores at baseline and follow-up were 28.3 and 22.3, with an SRM of 0.69 (P = 0.002) for 42 joints, and 36 and 27.7, with an SRM of 0.76 (P = 0.003) for the reduced joints, respectively.

CONCLUSION

A limited MSUS examination called musculoskeletal ultrasound in childhood arthritis limited examination (MUSICAL) captures all patients with active synovitis, and our new joint-specific scoring system is highly reliable and sensitive to change.

Clinical remission and subsequent relapse in patients with juvenile idiopathic arthritis: predictive factors according to therapeutic approach

BACKGROUND

Juvenile idiopathic arthritis constitutes a significant cause of disability and quality of life impairment in pediatric and adult patients. The aim of this study was to ascertain clinical remission (CR) and subsequent relapse in juvenile idiopathic arthritis (JIA) patients, according to therapeutic approach and JIA subtype. Evidence in literature regarding its predictors is scarce.

METHODS

We conducted an observational, ambispective study. Patients diagnosed of JIA, treated with synthetic and/or biologic disease modifying antirheumatic drugs (DMARD) were included and followed-up to December 31st, 2015. Primary outcome was clinical remission defined by Wallace criteria, both on and off medication. In order to ascertain CR according to therapeutic approach, DMARD treatments were divided in four groups: 1) synthetic DMARD (sDMARD) alone, 2) sDMARD combined with another sDMARD, 3) sDMARD combined with biologic DMARD (bDMARD), and 4) bDMARD alone.

RESULTS

A total of 206 patients who received DMARD treatment were included. At the time the follow-up was completed, 70% of the patients in the cohort had attained CR at least once (144 out of 206), and 29% were in clinical remission off medication (59 out of 206). According to treatment group, CR was more frequently observed in patients treated with synthetic DMARD alone (53%). Within this group, CR was associated with female sex, oligoarticular persistent subtypes, ANA positivity, Methotrexate treatment and absence of HLA B27, comorbidities and DMARD toxicity. 124 DMARD treatments (62%) were withdrawn, 64% of which relapsed. Lower relapse rates were observed in those patients with persistent oligoarticular JIA (93%) when DMARD dose was tapered before withdrawal (77%).

CONCLUSIONS

More than two thirds of JIA patients attained CR along the 9 years of follow-up, and nearly one third achieved CR off medication. Females with early JIA onset, lower active joint count and ANA positivity were the ones achieving and sustaining remission more frequently, especially when receiving synthetic DMARD alone and in the absence of HLA B27, comorbidities or previous DMARD toxicity.

Outcome of children with oligoarticular juvenile idiopathic arthritis compared to polyarthritis on methotrexate- data of the German BIKER registry

BACKGROUND

Oligoarticular juvenile idiopathic arthritis (oligoJIA) is the most commonly diagnosed category of chronic arthritis in children. Nevertheless, there are no evidence- based guidelines for its treatment, in particular for the use of methotrexate (MTX). The primary objective of this analysis is to evaluate the outcomes in patients with persistent oligoJIA compared to those with extended oligoJIA and rheumatoid factor (RF) negative polyarthritis treated with methotrexate.

METHODS

Patients with persistent or extended oligoJIA or RF negative PA recorded in the Biologics in Pediatric Rheumatology Registry (BiKeR), receiving methotrexate for the first time were included in the analyses. Efficacy was determined using the Juvenile Arthritis Disease Activity Score 10 (JADAS 10). Safety assessment included the documentation of adverse and serious adverse events.

RESULTS

From 2005 through 2011, 1056 patients were included: 370 patients with persistent oligoJIA, 221 patients with extended oligoJIA and 467 patients with RF negative PA. Therapeutic efficacy was observed following the start of methotrexate. Over a period of 24 months JADAS-minimal disease activity (JADAS ≤2) was reached in 44% of patients with persistent oligoJIA, 38% with extended oligoJIA, 46% with RF negative PA, JADAS-remission defined as JADAS ≤1 was reached in 33% of patients with persistent oligoJIA, 29% with extended oligoJIA and 35% (RF negative PA). Patients with extended oligoJIA achieved JADAS remission significantly later and received additional biologic disease-modifying drugs significantly more often than patients with persistent oligoJIA or RF negative PA (p < 0.001). Tolerability was comparable. New onset uveitis occurred in 0.3 to 2.2 per 100 patient years.

CONCLUSIONS

Patients with persistent oligoJIA taking methotrexate are at least as likely to enter remission as patients with extended oligo JIA or polyarticular JIA. Patients with extended oligoJIA achieved JADAS remission significantly later. Within 2 years, almost half of the patients with persistent oligoJIA achieved JADAS-minimal disease activity.

Adverse drug reactions associated with treatment in patients with chronic rheumatic diseases in childhood: a retrospective real life review of a single center cohort

BACKGROUND

Adverse drug reactions (ADRs) are the sixth leading causes of death worldwide; monitoring them is fundamental, especially in patients with disorders like chronic rheumatic diseases (CRDs). The study aimed to describe the ADRs investigating their severity and associated factors and resulting interventions in pediatric patients with CRDs.

METHODS

A retrospective, descriptive and analytical study was conducted on a cohort of children and adolescents with juvenile idiopathic arthritis (JIA), juvenile systemic lupus erythematosus (JSLE) and juvenile dermatomyositis (JDM). The study evaluated medical records of the patients to determine the causality and the management of ADRs. In order to investigate the risk factors that would increase the risk of ADRs, a logistic regression model was carried out on a group of patients treated with the main used drug.

RESULTS

We observed 949 ADRs in 547 patients studied. Methotrexate (MTX) was the most frequently used medication and also the cause of the most ADRs, which occurred in 63.3% of patients, followed by glucocorticoids (GCs). Comparing synthetic disease-modifying anti-rheumatic drugs (sDMARDs) vs biologic disease-modifying anti-rheumatic drugs (bDMARDs), the ADRs attributed to the former were by far higher than the latter. In general, the severity of ADRs was moderate and manageable. Drug withdrawal occurred in almost a quarter of the cases. In terms of risk factors, most patients who experienced ADRs due to MTX, were 16 years old or younger and received MTX in doses equal or higher than 0.6 mg/kg/week. Patients with JIA and JDM had a lower risk of ADRs than patients with JSLE. In the multiple regression model, the use of GCs for over 6 months led to an increase of 0.5% in the number of ADRs.

CONCLUSIONS

Although the ADRs highly likely affect a wide range of children and adolescents with CRDs they were considered moderate and manageable cases mostly. However, triggers of ADRs need further investigations.

Juvenile idiopathic arthritis in a center in the Western Anatolia region in Turkey

Aim:

To demonstrate the demographic data, subgroup distributions, responses to treatment and outcomes of long-term follow-up in patients who were followed up and treated in our clinics with a diagnosis of juvenile idiopathic arthritis, and to compare these data with national and international data.

Material and Methods:

The files of 116 patients who had been diagnosed as having juvenile idiopathic arthritis, were initiated on treatment and presented for regular follow-up visits between January 2012 and January 2018, were examined. Their demographic findings, treatments, active/inactive disease states (on-medication and off-medication) and treatment response states were evaluated.

Results:

According to the International League of Associations for Rheumatology criteria, the subtypes were specified as enthesitis-related arthritis (n=38), oligoarticular (n=37), rheumatoid factor (-) polyarticular (n=17), systemic (n=15), rheumatoid factor (+) polyarticular (n=5), and psoriatic juvenile idiopathic arthritis (n=4). In total, the female/male ratio was found to be 1.5. The mean delay time between the first complaint and the diagnosis was found to be 5.7±5.2 months. The patients with systemic type were diagnosed at the earliest, while the patients with polyarticular and enthesitis-related subtypes were diagnosed at the latest. Thirty-two percent of the patients were treated with methotrexate alone, and 38% were given additional biologic drugs. In both treatment groups, the time to achieve inactive disease was the shortest in the oligoarticular group and the longest in the enthesitis-related arthritis group. In the study period, 38 patients were in remission off-medication (the highest rate (53.3%) was observed in the systemic group) and 71 patients were in remission on-medication (the highest rate (70.2%) was observed in the oligoarticular group). Remission was obtained in 94% of the patients.

Conclusion:

Enthesitis which is the remarkable finding of enthesitis-related arthritis, should not be overlooked in routine physical examination. Awareness of enthesitis can contribute to the prevention of diagnostic delay in children with enthesitis-related arthritis.

DANILKO K, A. MALIEVSKY V, O. KARIMOV D, B. BAKIROV A, V. VIKTOROVA T. The relationship of the immune response mediator genes’ polymorphic variants with the methotrexate efficacy in juvenile idiopathic arthritis

Background/aim

The aim of the study was to analyze the relationship of the immune response mediator genes’ polymorphic loci (TNFA rs1800629, LTA rs909253, IL1B rs16944, IL2-IL21 rs6822844, IL2RA rs2104286, IL6 rs1800795, IL10 rs1800872, MIF rs755622, CTLA4 rs3087243, NFKB1 rs28362491, PTPN22 rs2476601, PADI4 rs2240336) variants with the methotrexate efficacy in juvenile idiopathic arthritis (JIA).

Materials and methods

The study included 274 JIA patients from the Republic of Bashkortostan, Russia. Achieving the American College of Rheumatology Pediatric 30 (ACR Pedi 30) response was regarded as the presence of the response to methotrexate (otherwise, as the absence), while achieving clinical remission on medication (Wallace et al., 2011) - as the sufficient response (otherwise, as the insufficient). Genotyping was conducted by the real-time polymerase chain reaction.

Results

Associations with an altered risk of the nonresponse to methotrexate in JIA were observed for the alleles/genotypes of the lociIL10 rs1800872 (in girls) and NFKB1 rs28362491 (in girls); with an altered risk of the insufficient response to methotrexate in JIA – for the alleles/genotypes of the loci IL1B rs16944 (in boys), CTLA4 rs3087243 (in boys), NFKB1 rs28362491 (in girls) and the haplotype TNFA rs1800629*A - LTA rs909253*G (in girls).

Conclusion

As a result of the study, the relationship of the alleles/genotypes of the IL1B rs16944, IL10 rs1800872, CTLA4 rs3087243, NFKB1 rs28362491 polymorphic lociand the TNFA rs1800629*A - LTA rs909253*G haplotype with the methotrexate efficacy in JIA was established (taking into account the differences by sex).

[Methotrexate in juvenile idiopathic arthritis. Adverse effects and associated factors]

INTRODUCTION

Methotrexate (MTX) is the drug of choice for juvenile idiopathic arthritis. Its clinical efficacy is limited due to the development of adverse effects (AEs).

PATIENTS AND METHODS

A retrospective observational study was conducted on the AEs associated with MTX therapy in children diagnosed with juvenile idiopathic arthritis followed-up in a tertiary hospital between 2008 and 2016.

RESULTS

The study included a total of 107 patients, of whom 71 (66.3%) were girls (66.3%). The median age at diagnosis was 6.4 years (IQR 3.1-12.4), with a median follow-up of 45.7 months (IQR 28.8-92.4). There were 48 patients (44.9%) with oligoarthritis, and 26 children (24.3%) with rheumatoid-factor negative polyarthritis. Of these, 52/107 (48.6%) developed AEs, with the most frequent being gastrointestinal symptoms (35.6%) and behavioural problems (35.6%). An age older than 6 years at the beginning of therapy increased the risk of developing AEs, both in the univariate (OR=3.5; 95% CI: 1.5-7.3) and multivariate (12% increase per year) analyses. The doses used, administration route, or International League of Associations for Rheumatology (ILAR) classification, were not associated with the development of AEs. Twenty children required a dosage or route of administration modification, which resolved the AE in 11 (55%) cases. MTX was interrupted due to the development of AEs in 37/107 patients (34.6%), mainly due to increased plasma transaminases (n=14, 37.8%), gastrointestinal symptoms (n=9, 24.3%) and behavioural problems (n=6, 16.3%).

CONCLUSIONS

MTX is the therapy of choice for patients with juvenile idiopathic arthritis, but 50% of the children develop some form of AE. Although the AEs are not severe, they lead to interruption of therapy in 35% of the children.

A prediction rule for lack of achievement of inactive disease with methotrexate as the sole disease-modifying antirheumatic therapy in juvenile idiopathic arthritis

BACKGROUND

To investigate the frequency of achievement of inactive disease (ID) in children with juvenile idiopathic arthritis (JIA) treated with methotrexate (MTX) as the sole disease-modifyng antirheumatic (DMARD) therapy and to develop a prediction model for lack of attainment of ID.

METHODS

The clinical charts of consecutive patients started with MTX as the sole DMARD between 2000 and 2013 were reviewed. Patient follow-up was censored at first episode of ID or, in case ID was not reached, at last follow-up visit or when a biologic DMARD was prescribed. The characteristic at MTX start of patients who achieved or did not achieve ID were compared with univariate and multivariable analyses. Regression coefficients (β) of variables that entered the best-fitting logistic regression model were converted and summed to obtain a "prediction score" for lack of achievement of ID.

RESULTS

A total of 375 patients were included in the study. During MTX administration, 8.8% were given systemic corticosteroids and 44.1% intra-articular corticosteroids. After MTX start, 229 (61%) patients achieved ID after a median of 1.7 years, whereas 146 patients (39%) did not reach ID after a median of 1.2 years. On multivariable analysis, independent correlations with lack of achievement of ID were identified for the disease categories of systemic arthritis, enthesitis-related arthritis (ERA) and polyarthritis and C-reactive protein (CRP) >  1.4 mg/dl. The prediction score ranged from 0 to 3 and its cutoff that discriminated best between patients who achieved or did not achieve ID was > 0.5. The categories of systemic arthritis or ERA, both of which had a score greater than 0.5, were sufficient alone to predict a lower likelihood to reach ID. Polyarthritis and increased CRP, whose score was 0.5, assumed a predictive value only when present in association.

CONCLUSION

A conventional treatment regimen based on MTX as the sole DMARD led to achievement of ID in a sizeable proportion of children with JIA. Our findings help to outline the characteristics of patients who may deserve a synthetic DMARD other than MTX or the introduction of a biologic DMARD from disease outset.

Efficacy of High-Dose Methotrexate in Pediatric Non-Infectious Uveitis

Purpose: To analyze the efficacy of high dose (≥ 15mg/m2/week) methotrexate (MTX) versus low dose (<15mg/m2/week) MTX in relation to time to remission on medication.Methods: Retrospective observational cohort study of pediatric patients with auto-immune uveitis with or without underlying systemic disease treated with MTX at the University Medical Center Groningen (the Netherlands) between 1990 and 2014. Primary outcome was time to remission on medication, which was defined as an observable inactive disease in the affected eye for longer than 3 months without the use of systemic corticosteroids.Results: A total of 42 patients were included. Mean age at uveitis diagnosis was 6.5 years (range 1.7 - 14.4), and 22 (52.4%) patients were male. Bilateral disease was found in 33 patients. Most patients (n=25) had anterior uveitis. JIA was the underlying systemic disease in 21 patients. Overall, 28 (66.7%) patients reached remission on medication in (median) 22.5 months (IQR 10.4- 45). Time to remission on medication in the low dose group (median 35.2, IQR 20.5 - 72.1 months) was significantly longer than in the high dose group (median 16.6, IQR 7.8 - 22.5 months) (p= 0.01). No statistically significant differences in ocular complications, steroid-sparing effect, cumulative dosage and side effects of MTX were found between the high and low dose groups.Conclusion: In this retrospective study on pediatric auto-immune uveitis, high dose MTX was associated with a shorter time to remission on medication as compared to low dose MTX, while side effects were comparable in both groups.

Management of Paediatric Ulcerative Colitis, Part 1: Ambulatory Care-An Evidence-based Guideline From European Crohn's and Colitis Organization and European Society of Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

The contemporary management of ambulatory ulcerative colitis (UC) continues to be challenging with ∼20% of children needing a colectomy within childhood years. We thus aimed to standardize daily treatment of pediatric UC and inflammatory bowel diseases (IBD)-unclassified through detailed recommendations and practice points.

METHODS

These guidelines are a joint effort of the European Crohn's and Colitis Organization (ECCO) and the Paediatric IBD Porto group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN). An extensive literature search with subsequent evidence appraisal using robust methodology was performed before 2 face-to-face meetings. All 40 included recommendations and 86 practice points were endorsed by 43 experts in Paediatric IBD with at least an 88% consensus rate.

RESULTS

These guidelines discuss how to optimize the use of mesalamine (including topical), systemic and locally active steroids, thiopurines and, for more severe disease, biologics. The use of other emerging therapies and the role of surgery are also covered. Algorithms are provided to aid therapeutic decision-making based on clinical assessment and the Paediatric UC Activity Index (PUCAI). Advice on contemporary therapeutic targets incorporating the use of calprotectin and the role of therapeutic drug monitoring are presented, as well as other management considerations around pouchitis, extraintestinal manifestations, nutrition, growth, psychology, and transition. A brief section on disease classification using the PIBD-classes criteria and IBD-unclassified is also part of these guidelines.

CONCLUSIONS

These guidelines provide a guide to clinicians managing children with UC and IBD-unclassified management to provide modern management strategies while maintaining vigilance around appropriate outcomes and safety issues.

Relationship Between Polymorphisms in Methotrexate Pathway Genes and Outcome of Methotrexate Treatment in a Cohort of 119 Patients with Juvenile Idiopathic Arthritis

OBJECTIVE

To identify clinical and pharmacogenetic determinants of efficacy and toxicity of methotrexate (MTX) in juvenile idiopathic arthritis (JIA) over time.

METHODS

A cohort of 119 consecutive patients with JIA treated with MTX was reviewed. The Juvenile Arthritis Disease Activity Score including 71 joints was used to measure disease activity. Nonresponders were patients who did not reach a minimum of 30% improvement after 6 months of treatment or were switched to biologic drugs in the first 6 months because of inefficacy. All adverse events (AE) were noted. Genotyping of single-nucleotide polymorphisms (SNP) in the genes coding for MTX transporters, folate pathway, and adenosine pathway was performed using real-time PCR methods. Univariate and multivariable penalized logistic and Cox regression were used to analyze data.

RESULTS

Thirty patients (25.8%) were defined as nonresponders and 55 (47.2%) were switched to biologics during the followup. Sixty-five patients (54.5%) reported AE in a total of 405 patient-years, and 10 patients (8.4%) discontinued MTX because of AE. AMPD1 rs17602729 and MTHFD1 rs2236225 were associated with gastrointestinal AE while the latter together with MTRR rs1801394 also demonstrated associations with developing hepatoxicity. MTHFR rs1801131, ABCG2 rs2231137, wild-type of MTR rs1805087, and wild-type of ABCC2 rs2273697 were identified as potential markers for discontinuing MTX treatment because of AE. MTHFR rs1801133, MTRR rs1801394, and ABCC2 rs2273697 were associated with switching to biologics.

CONCLUSION

SNP in different MTX metabolic pathways influence treatment with MTX. Genetic variability is a better marker for toxicity than efficacy.

Methotrexate efficacy, but not its intolerance, is associated with the dose and route of administration

BACKGROUND

There is a lack of published evidence on the importance of methotrexate (MTX) dose and route of administration on both its efficacy and adverse events in children with Juvenile Idiopathic Arthritis (JIA). We aimed to document our clinical practice based on the treat-to-target approach in order to support the concept that better therapeutic effect achieved with an optimal dose of parenteral MTX is associated with clinically acceptable adverse effects comparable to those reported for oral treatment.

METHODS

Study inclusion criteria were indication of new MTX therapy for active arthritis in confirmed JIA patients younger than 18 years. Eligible patients were evaluated prospectively every 3 months for 1 year using standardized instruments for treatment response (American College of Rheumatology Pediatric (ACRPedi) response, Juvenile Arthritis Disease Activity Score (JADAS) 71, Clinically Inactive Disease (CID)) and adverse events (laboratory monitoring, Methotrexate Intolerance Severity Score (MISS)). MTX responders had to achieve at least ACRPedi 70 response. MTX intolerance was defined by MISS ≥ 6.

RESULTS

In 45/55 patients (81.8 %) MTX was started as subcutaneous injection. The initial median weekly dose was 14.4 mg/m(2) in parenteral and 11.7 mg/m(2) in oral administration. MTX therapy was effective in the level of ACRpedi70 and CID in 50.9 % and 30.9 % of patients at month 6 and in 70.9 % and 56.4 % after 12 months of the treatment, respectively. MTX intolerance at 6 and 12 months was noted in 25.5 % and 30.6 %, respectively. Management of intolerance included change in the dose and/or route of administration, education and councelling. Adverse events led to MTX withdrawal in 5 patients (9 %) due to toxicity (n = 3) and intolerance (n = 2). We did not find any significant predictive factors for either MTX therapeutic response or intolerance.

CONCLUSION

Subcutaneous MTX weekly dose around 15 mg/m(2) is associated not only with a high response rate within the first 12 months of treatment, but also with a relatively low rate of significant adverse effects that would lead to the treatment termination. It allows early recognition of MTX non-responders and addition of biologic therapy. Sustainability of therapeutic effect and longer-term evolution of adverse events will be addressed by an ongoing extension of the study.

Prediction of methotrexate intolerance in juvenile idiopathic arthritis: a prospective, observational cohort study

BACKGROUND

Methotrexate (MTX) is an effective and safe drug in the treatment of juvenile idiopathic arthritis (JIA). Despite its safety, MTX-related gastrointestinal adverse effects before and after MTX administration, termed MTX intolerance, occur frequently, leading to non-compliance and potentially premature MTX termination. The aim of this study was to construct a risk model to predict MTX intolerance.

METHODS

In a prospective JIA cohort, clinical variables and single nucleotide polymorphisms were determined at MTX start. The Methotrexate Intolerance Severity Score was employed to measure MTX intolerance in the first year of treatment. MTX intolerance was most prevalent at 6 or 12 months after MTX start, which was defined as the outcome for the prediction model. The model was developed in 152 patients using multivariable logistic regression analysis and subsequently internally validated using bootstrapping.

RESULTS

The prediction model included the following predictors: JIA category, antinuclear antibody, parent/patient assessment of pain, Juvenile Arthritis Disease Activity Score-27, thrombocytes, alanine aminotransferase and creatinine. The model classified 77.5% of patients correctly, and 66.7% of patients after internal validation by bootstrapping. The lowest predicted risk of MTX intolerance was 18.9% and the highest predicted risk was 85.9%. The prediction model was transformed into a risk score (range 0-17). At a cut-off of ≥6, sensitivity was 82.0%, specificity 56.1%, positive predictive value was 58.7% and negative predictive value 80.4%.

CONCLUSIONS

This clinical prediction model showed moderate predictive power to detect MTX intolerance. To develop into a clinically usable tool, it should be validated in an independent cohort and updated with new predictors. Such an easy-to-use tool could then assist clinicians in identifying patients at risk to develop MTX intolerance, and in turn to monitor them closely and intervene timely in order to prevent the development of MTX intolerance.

TRIAL REGISTRATION

ISRCTN register, www.isrctn.com, ISRCTN13524271.