In silico validation of the Autoinflammatory Disease Damage Index.

INTRODUCTION: Autoinflammatory diseases can cause irreversible tissue damage due to systemic inflammation. Recently, the Autoinflammatory Disease Damage Index (ADDI) was developed. The ADDI is the first instrument to quantify damage in familial Mediterranean fever, cryopyrin-associated periodic syndromes, mevalonate kinase deficiency and tumour necrosis factor receptor-associated periodic syndrome. The aim of this study was to validate this tool for its intended use in a clinical/research setting. METHODS: The ADDI was scored on paper clinical cases by at least three physicians per case, independently of each other. Face and content validity were assessed by requesting comments on the ADDI. Reliability was tested by calculating the intraclass correlation coefficient (ICC) using an 'observer-nested-within-subject' design. Construct validity was determined by correlating the ADDI score to the Physician Global Assessment (PGA) of damage and disease activity. Redundancy of individual items was determined with Cronbach's alpha. RESULTS: The ADDI was validated on a total of 110 paper clinical cases by 37 experts in autoinflammatory diseases. This yielded an ICC of 0.84 (95% CI 0.78 to 0.89). The ADDI score correlated strongly with PGA-damage (r=0.92, 95% CI 0.88 to 0.95) and was not strongly influenced by disease activity (r=0.395, 95% CI 0.21 to 0.55). After comments from disease experts, some item definitions were refined. The interitem correlation in all different categories was lower than 0.7, indicating that there was no redundancy between individual damage items. CONCLUSION: The ADDI is a reliable and valid instrument to quantify damage in individual patients and can be used to compare disease outcomes in clinical studies.

The safety of live-attenuated vaccines in patients using IL-1 or IL-6 blockade: an international survey.

BACKGROUND: Withholding live-attenuated vaccines in patients using interleukin (IL)-1 or IL-6 blocking agents is recommended by guidelines for both pediatric and adult rheumatic diseases, since there is a risk of infection in an immune suppressed host. However, this has never been studied. This retrospective, multicenter survey aimed to evaluate the safety of live-attenuated vaccines in patients using IL-1 or IL-6 blockade. METHODS: We contacted physicians involved in the treatment of autoinflammatory diseases to investigate potential cases. Patients were included if a live-attenuated vaccine had been administered while they were on IL-1 or IL-6 blockade. RESULTS: Seventeen patients were included in this survey (7 systemic juvenile idiopathic arthritis (sJIA), 5 cryopyrin associated periodic syndrome (CAPS), 4 mevalonate kinase deficiency (MKD) and 1 familial Mediterranean fever (FMF). Three patients experienced an adverse event, of which two were serious adverse events (a varicella zoster infection after varicella zoster booster vaccination, and a pneumonia after MMR booster). One additional patient had diarrhea after oral polio vaccine. Further, seven patients experienced a flare of their disease, which were generally mild. Eight patients did not experience an adverse event or a flare. CONCLUSION: We have described a case series of seventeen patients who received a live-attenuated vaccine while using IL-1 or IL-6 blocking medication. The findings of this survey are not a reason to adapt the existing guidelines. Prospective trials are needed in order to acquire more evidence about the safety and efficacy before considering adaptation of guidelines.

Diagnostic criteria for cryopyrin-associated periodic syndrome (CAPS).

Cryopyrin-associated periodic syndrome (CAPS) is a rare, heterogeneous disease entity associated with NLRP3 gene mutations and increased interleukin-1 (IL-1) secretion. Early diagnosis and rapid initiation of IL-1 inhibition prevent organ damage. The aim of the study was to develop and validate diagnostic criteria for CAPS. An innovative process was followed including interdisciplinary team building, item generation: review of CAPS registries, systematic literature review, expert surveys, consensus conferences for item refinement, item reduction and weighting using 1000Minds decision software. Resulting CAPS criteria were tested in large cohorts of CAPS cases and controls using correspondence analysis. Diagnostic models were explored using sensitivity analyses. The international team included 16 experts. Systematic literature and registry review identified 33 CAPS-typical items; the consensus conferences reduced these to 14. 1000Minds exercises ranked variables based on importance for the diagnosis. Correspondence analysis determined variables consistently associated with the diagnosis of CAPS using 284 cases and 837 controls. Seven variables were significantly associated with CAPS (p<0.001). The best diagnosis model included: Raised inflammatory markers (C-reactive protein/serum amyloid A) plus ≥two of six CAPS-typical symptoms: urticaria-like rash, cold-triggered episodes, sensorineural hearing loss, musculoskeletal symptoms, chronic aseptic meningitis and skeletal abnormalities. Sensitivity was 81%, specificity 94%. It performed well for all CAPS subtypes and regardless of NLRP3 mutation. The novel approach integrated traditional methods of evidence synthesis with expert consensus, web-based decision tools and innovative statistical methods and may serve as model for other rare diseases. These criteria will enable a rapid diagnosis for children and adults with CAPS.

Development of the autoinflammatory disease damage index (ADDI).

OBJECTIVES: Autoinflammatory diseases cause systemic inflammation that can result in damage to multiple organs. A validated instrument is essential to quantify damage in individual patients and to compare disease outcomes in clinical studies. Currently, there is no such tool. Our objective was to develop a common autoinflammatory disease damage index (ADDI) for familial Mediterranean fever, cryopyrin-associated periodic syndromes, tumour necrosis factor receptor-associated periodic fever syndrome and mevalonate kinase deficiency. METHODS: We developed the ADDI by consensus building. The top 40 enrollers of patients in the Eurofever Registry and 9 experts from the Americas participated in multiple rounds of online surveys to select items and definitions. Further, 22 (parents of) patients rated damage items and suggested new items. A consensus meeting was held to refine the items and definitions, which were then formally weighted in a scoring system derived using decision-making software, known as 1000minds. RESULTS: More than 80% of the experts and patients completed the online surveys. The preliminary ADDI contains 18 items, categorised in the following eight organ systems: reproductive, renal/amyloidosis, developmental, serosal, neurological, ears, ocular and musculoskeletal damage. The categories renal/amyloidosis and neurological damage were assigned the highest number of points, serosal damage the lowest number of points. The involvement of (parents of) patients resulted in the inclusion of, for example, chronic musculoskeletal pain. CONCLUSIONS: An instrument to measure damage caused by autoinflammatory diseases is developed based on consensus building. Patients fulfilled a significant role in this process.

The Phenotype and Genotype of Mevalonate Kinase Deficiency: A Series of 114 Cases From the Eurofever Registry.

OBJECTIVE: Mevalonate kinase deficiency (MKD) is a rare metabolic disease characterized by recurrent inflammatory episodes. This study was undertaken to describe the genotype, phenotype, and response to treatment in an international cohort of MKD patients. METHODS: All MKD cases were extracted from the Eurofever registry (Executive Agency for Health and Consumers project no. 2007332), an international, multicenter registry that retrospectively collects data on children and adults with autoinflammatory diseases. RESULTS: The study included 114 MKD patients. The median age at onset was 0.5 years. Patients had on average 12 episodes per year. Most patients had gastrointestinal symptoms (n = 112), mucocutaneous involvement (n = 99), lymphadenopathy (n = 102), or musculoskeletal symptoms (n = 89). Neurologic symptoms included headache (n = 43), cerebellar syndrome (n = 2), and mental retardation (n = 4). AA amyloidosis was noted in 5 patients, almost twice as many as expected from findings in previous cohorts. Macrophage activation syndrome occurred in 1 patient. Patients were generally well between attacks, but 10-20% of the patients had constitutional symptoms, such as fatigue, between fever episodes. Patients with p.V377I/p.I268T compound heterozygosity had AA amyloidosis significantly more often. Patients without a p.V377I mutation more often had severe musculoskeletal involvement. Treatment with nonsteroidal antiinflammatory drugs relieved symptoms. Steroids given during attacks, anakinra, and etanercept appeared to improve symptoms and could induce complete remission in patients with MKD. CONCLUSION: We describe the clinical and genetic characteristics of 114 MKD patients, which is the largest cohort studied so far. The clinical manifestations confirm earlier reports. However, the prevalence of AA amyloidosis is far higher than expected.

Recommendations for the management of autoinflammatory diseases.

: Autoinflammatory diseases are characterised by fever and systemic inflammation, with potentially serious complications. Owing to the rarity of these diseases, evidence-based guidelines are lacking. In 2012, the European project Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) was launched to optimise and disseminate regimens for the management of children and young adults with rheumatic diseases, facilitating the clinical practice of paediatricians and (paediatric) rheumatologists. One of the aims of SHARE was to provide evidence-based recommendations for the management of the autoinflammatory diseases cryopyrin-associated periodic syndromes (CAPS), tumour necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) and mevalonate kinase deficiency (MKD). These recommendations were developed using the European League Against Rheumatism standard operating procedure. An expert committee of paediatric and adult rheumatologists was convened. Recommendations derived from the systematic literature review were evaluated by an online survey and subsequently discussed at a consensus meeting using Nominal Group Technique. Recommendations were accepted if more than 80% agreement was reached. In total, four overarching principles, 20 recommendations on therapy and 14 recommendations on monitoring were accepted with ≥80% agreement among the experts. Topics included (but were not limited to) validated disease activity scores, therapy and items to assess in monitoring of a patient. By developing these recommendations, we aim to optimise the management of patients with CAPS, TRAPS and MKD.

Evidence-based recommendations for genetic diagnosis of familial Mediterranean fever.

Familial Mediterranean fever (FMF) is a disease of early onset which can lead to significant morbidity. In 2012, Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) was launched with the aim of optimising and disseminating diagnostic and management regimens for children and young adults with rheumatic diseases. The objective was to establish recommendations for FMF focusing on provision of diagnostic tools for inexperienced clinicians particularly regarding interpretation of MEFV mutations. Evidence-based recommendations were developed using the European League against Rheumatism standard operating procedure. An expert committee of paediatric rheumatologists defined search terms for the systematic literature review. Two independent experts scored articles for validity and level of evidence. Recommendations derived from the literature were evaluated by an online survey and statements with less than 80% agreement were reformulated. Subsequently, all recommendations were discussed at a consensus meeting using the nominal group technique and were accepted if more than 80% agreement was reached. The literature search yielded 3386 articles, of which 25 were considered relevant and scored for validity and level of evidence. In total, 17 articles were scored valid and used to formulate the recommendations. Eight recommendations were accepted with 100% agreement after the consensus meeting. Topics covered were clinical versus genetic diagnosis of FMF, genotype-phenotype correlation, genotype-age at onset correlation, silent carriers and risk of amyloid A (AA) amyloidosis, and role of the specialist in FMF diagnosis. The SHARE initiative provides recommendations for diagnosing FMF aimed at facilitating improved and uniform care throughout Europe.

Treatment of hereditary autoinflammatory diseases.

PURPOSE OF REVIEW: The purpose of this review is to summarize recent advances in the treatment of the hereditary autoinflammatory diseases, focusing on Familial Mediterranean fever (FMF), tumor necrosis factor receptor-associated periodic syndrome (TRAPS), cryopyrin-associated periodic syndromes (CAPS) and mevalonate kinase deficiency (MKD). We discuss recently published studies and their implications for current patient care and future clinical research. RECENT FINDINGS: Interleukin (IL)-1 blockade is effective in most autoinflammatory conditions. Younger patients require a higher dose per kg of body weight. In FMF, colchicine remains the treatment of choice. Single daily dosing appears adequate. When colchicine fails, IL-1 blockade is effective. In CAPS, the beneficial effect of IL-1 blockade is sustained, and side-effects are limited. There is no evidence that one IL-1 blocker is superior to the other. In TRAPS and MKD, IL-1 blockade appears effective. Some patients have sufficient suppression of inflammatory symptoms with NSAIDs or corticosteroids. SUMMARY: Apart from CAPS and FMF, therapy of autoinflammatory diseases is based on small and retrospective studies. IL-1 blockade appears effective, but larger prospective trials are needed, especially in MKD, TRAPS and colchicine-resistant FMF patients.

Treatment of autoinflammatory diseases: results from the Eurofever Registry and a literature review.

OBJECTIVE: To evaluate the response to treatment of autoinflammatory diseases from an international registry and an up-to-date literature review. METHODS: The response to treatment was studied in a web-based registry in which clinical information on anonymised patients with autoinflammatory diseases was collected retrospectively as part of the Eurofever initiative. Participating hospitals included paediatric rheumatology centres of the Paediatric Rheumatology International Trial Organisation network and adult centres with a specific interest in autoinflammatory diseases. The following diseases were included: familial Mediterranean fever (FMF), cryopyrin-associated periodic syndromes (CAPS), tumour necrosis factor (TNF)-receptor associated periodic syndrome (TRAPS), mevalonate kinase deficiency (MKD), pyogenic arthritis pustulosis acne (PAPA) syndrome, deficiency of interleukin-1 receptor antagonist (DIRA), NLRP12-related periodic fever and periodic fever aphthosis pharyngitis adenitis (PFAPA) syndrome. Cases were independently validated by experts for each disease. A literature search regarding treatment of the abovementioned diseases was also performed using Medline and Embase. RESULTS: 22 months from the beginning of the enrolment, complete information on 496 validated patients was available. Data from the registry in combination with evidence from the literature confirmed that colchicine is the treatment of choice for FMF and IL-1 blockade for DIRA and CAPS. Corticosteroids on demand probably represent a valid therapeutic strategy for PFAPA, but also for MKD and TRAPS. Patients with poorly controlled MKD, TRAPS, PAPA or FMF may benefit from IL-1 blockade; anti-TNF treatment may represent a possible valuable alternative. CONCLUSIONS: In the absence of high-grade evidence, these results could serve as a basis for therapeutic guidelines and to identify candidate drugs for future therapeutic trials.

Mevalonate kinase deficiency, a metabolic autoinflammatory disease.

Mevalonate kinase deficiency is a rare autosomal recessive inborn error of metabolism with an autoinflammatory phenotype. In this review we discuss its pathogenesis, clinical presentation and treatment. Mutations in both copies of the MVK-gene lead to a block in the mevalonate pathway. Interleukin-1beta mediates the inflammatory phenotype. Shortage of a non-sterol isoprenoid product of the mevalonate pathway, Geranylgeranylpyrophosphate leads to aberrant activation of the small GTPase Rac1, and inflammasome activation. The clinical phenotype ranges widely, depending on the severity of the enzyme defect. All patients show recurrent fevers, lymphadenopathy and high acute phase proteins. Severely affected patients have antenatal disease onset, dysmorphic features, growth retardation, cognitive impairment and progressive ataxia. Diagnosis relies on mutation analysis of the MVK-gene. There is no evidence based therapy. IL-1 blockade is usually effective. Severe cases require allogeneic stem cell transplantation. Targeted therapies are needed.