Phenotypic and genotypic characteristics of cryopyrin-associated periodic syndrome: a series of 136 patients from the Eurofever Registry

Muckle-Wells Syndrome Across Four Generations in One Czech Family: Natural Course of the Disease

Background: Muckle-Wells syndrome (MWS) represents a moderate phenotype of cryopyrinopathies. Sensorineural hearing loss and AA amyloidosis belong to the most severe manifestations of uncontrolled disease. Simultaneous discovery of MWS in four generations of one large kindred has enabled us to document natural evolution of untreated disease and their response to targeted therapy.

Methods: A retrospective case study, clinical assessment at the time of diagnosis and 2-year prospective follow-up using standardized disease assessments were combined.

Results: Collaborative effort of primary care physicians and pediatric and adult specialists led to identification of 11 individuals with MWS within one family. Presence of p.Ala441Val mutation was confirmed. The mildest phenotype of young children suffering with recurrent rash surprised by normal blood tests and absence of fevers. Young adults all presented with fevers, rash, conjunctivitis, and arthralgia/arthritis with raised inflammatory markers. Two patients aged over 50 years suffered with hearing loss and AA amyloidosis. IL-1 blockade induced disease remission in all individuals while hearing mildly improved or remained stable in affected patients as did renal function in one surviving individual with amyloidosis.

Conclusions: We have shown that severity of MWS symptoms gradually increased with age toward distinct generation-specific phenotypes. A uniform trajectory of disease evolution has encouraged us to postpone institution of IL-1 blockade in affected oligosymptomatic children. This report illustrates importance of close interdisciplinary collaboration.

State of care for patients with systemic autoinflammatory diseases - Results of a tertiary care survey

BACKGROUND

Systemic autoinflammatory diseases (SAIDs) are rare debilitating disorders of which there is limited awareness and a significant delay in diagnosis. There is no uniform approach in the diagnosis and treatment of these disorders and the real life state of SAID patient care is poorly characterized. The aim of this study was to obtain data on the epidemiology, state of care and the perception of physicians who are involved in the care of SAID patients.

METHODS

We performed a questionnaire-based survey and contacted 134 university departments of dermatology, pediatrics, rheumatology and other SAID departments of tertiary care in German-speaking countries.

RESULTS

A total of 37 departments participated in the survey. The majority of departments managed both adult and pediatric patients with a variety of monogenic and polygenic/acquired SAIDs. For monogenic SAIDs such as cryopyrin-associated periodic syndromes (CAPS) and familial Mediterranean fever (FMF), the diagnostic and treatment strategies were similar among the departments. The diagnostic work-up included inflammatory markers and genetic testing, the first line treatment interleukin-1 (IL-1) blockers for CAPS and colchicine for FMF. For polygenic/acquired SAIDs, we observed a significant heterogeneity in diagnostic and therapeutic approaches. As a major unmet need, diagnostic delay was identified with a median time to diagnosis of 2 (range 1-5) years. The overall state of care for SAID patients was rated to be excellent or good by only 12% of departments, and to be poor or non-sufficient by 40% of departments.

CONCLUSION

This study demonstrates a high need to improve the state of care and to harmonize diagnostic and treatment strategies for SAID patients.

Chronic urticaria in infants as the first manifestation of autoinflammatory disease

We report two unrelated infants in whom chronic urticaria was the first clinical manifestation of cryopyrin-associated periodic syndrome, which should be suspected in infants with early-onset chronic urticaria, especially if there is a neutrophil-rich infiltrate in the skin biopsy. Early diagnosis of cryopyrin-associated periodic syndrome may lead to early and successful treatment with anti-interleukin-1 medications.

Early canakinumab therapy for the sensorineural deafness in a family with Muckle-Wells syndrome due to a novel mutation of NLRP3 gene

Cryopyrin-associated periodic syndrome (CAPS) is one of the autoinflammatory disorders caused by mutations in NLRP3 gene. The over-production of interleukin (IL)-1β induced by NLRP3 gene mutations plays an important role in the pathophysiology of CAPS. We diagnosed 3 patients with CAPS, who were lineal family members having a novel mutation of NLRP3 gene. The objective of this report is to compare the characteristics of symptoms and differences in the therapeutic responses of them, who had the same mutation. In addition, we aimed to examine the usefulness of cytokine measurement for diagnosis or determination of treatment effect of CAPS. A 5-year-old Japanese boy (proband) came to our hospital because of short stature, reached the diagnosis of Muckle-Wells syndrome (MWS) due to a mutation in NLRP3 gene, which had not been reported so far (p.G328E, c.G983A). His mother and grandmother harbored the same mutation of NLRP3. We measured serum concentrations of cytokines in the proband assessed by flow-cytometric bead array. All of them had episodic skin eruptions with conjunctivitis, hearing loss, and arthralgia, but not periodic fever, cold-triggered episodes, and chronic aseptic meningitis. Only the proband had short stature. Canakinumab therapy led to a prompt relief of symptoms and normalized laboratory data in all patients. Audiograms demonstrated an improved hearing level in the proband, but not two others despite of the same mutation. All cytokines did not show any characteristic findings. Sensorineural hearing loss and itchless rash but not serum cytokine profile deserved attention to the diagnosis and treatment start of CAPS. The early intervention of IL-1β blockade may reduce the chance of complete deafness in patients with CAPS.

Cryopyrin-Associated Periodic Fever Syndrome and the Nervous System

PURPOSE OF REVIEW

The purpose of this review is to highlight the molecular and clinical characteristics of the cryopyrin-associated periodic fever syndrome (CAPS) and its management. CAPS is an autosomal dominantly inherited autoinflammatory disorder associated with mutations in the NLRP3 gene, which ultimately lead to excessive production of interleukin-1β (IL-1β) and systemic inflammation. Typical systemic features include fever, urticarial rash and arthralgia, and ultimately amyloidosis. There are also multiple neurological manifestations including, but not restricted to, headache, sensorineural hearing loss, aseptic meningitis, myalgia and optic nerve involvement.

RECENT FINDINGS

Since the recognition of CAPS as a single disease entity and discovery of the underlying causative gene, there has been a major breakthrough in terms of its treatment by pharmacological IL-1β inhibition. Highly targeted therapies against IL-1 have been shown to be remarkably effective in the treatment of CAPS and make early diagnosis of this condition crucial. It is hoped that starting pharmacological intervention in a timely manner will prove neuroprotective. There are three drugs licensed for treatment of CAPS; canakinumab, anakinra and rilonacept. The former two are widely used: canakinumab is a fully humanised anti-IL-1β monoclonal antibody administered as a subcutaneous injection once every 8 weeks starting at a dose of 150 mg in patients weighing more than 40 kg. Anakinra is a recombinant form of the IL-1 receptor antagonist and the adult daily dose is 100 mg subcutaneously. CAPS is a highly debilitating disorder characterised by unregulated IL-1β production driven by autosomal dominantly inherited mutations in the NLRP3 gene. Effective therapies targeted against IL-1 are now available and are vital to prevent long-term complications.

A clinical update on inflammasomopathies

Inflammasomes are important elements of the innate immune defense. The most common autoinflammatory syndromes, as well a number of rare ones, are due to hereditary defects in the inflammasomes, hence are called inflammasomopathies. The recent clinical advances in these diseases will be reviewed, with special emphasis on reflecting the international collaborative work in the field. Recent recommendations for familial Mediterranean fever, cryopyrin-associated periodic syndromes and hyper-IgD syndrome/mevalonate kinase deficiency will be presented and diagnostics tests, treatment alternatives and follow-up recommendations will be summarized. The other rare inflammasomopathies will be briefly discussed based on clinical features; these diseases are pyogenic arthritis, pyoderma gangrenosum and acne, NLRC4-related macrophage-activation syndrome of enterocolitis, mutations in NLRP12 that cause hereditary periodic fever syndromes (familial cold inflammatory syndrome 2) and NLRP1-associated autoinflammation with arthritis and dyskeratosis.

Mimickers of Urticaria: Urticarial Vasculitis and Autoinflammatory Diseases

A wide differential diagnosis must be considered in a patient presenting with urticarial plaques. Although acute and chronic urticaria are the commonest diagnoses, other differential diagnoses include polymorphous eruption of pregnancy, mast cell disorders, hypereosinophilic syndrome, urticarial vasculitis, pemphigoid, systemic lupus erythematosus, and autoinflammatory disease. This review will specifically address urticarial vasculitis and autoinflammatory syndromes. These entities represent contrasting examples of urticarial-like lesions resulting from either an adaptive immune complex-mediated mechanism (urticarial vasculitis) or an innate immune-mediated mechanism (autoinflammatory disorders), with differing therapeutic implications. In patients presenting with painful, persistent plaques that last more than 24 hours and resolve with bruising of the skin, consideration should be given to a diagnosis of urticarial vasculitis. A biopsy should be obtained to ascertain this diagnosis. In patients presenting with a persistent history of recurrent urticarial plaques associated with signs of systemic inflammation including fevers and elevated inflammatory markers (C-reactive protein [CRP]/serum amyloid A, leukocytosis, and negative connective tissue serologies), consideration should be given to autoinflammatory disorders: the 3 cryopyrin-associated periodic syndromes, Schnitzler syndrome, and familial cold autoinflammatory syndrome 2. Serum protein electrophoresis should be checked to rule out an underlying monoclonal gammopathy.

Cryopyrin-associated periodic syndrome in early childhood can be successfully treated with interleukin-1 blockades

Cryopyrin-associated periodic syndrome (CAPS) is caused by a mutation in the NLRP3 gene encoding cryopyrin production. Overproduction of interleukin-1 (IL-1) leads to symptoms that are associated with elevated inflammatory markers, including periodic fever and a rash. We provide a clinical overview of CAPS in children, including three Finnish case studies.

CONCLUSION

When CAPS has been diagnosed, an IL-1 blockade with biological should be introduced to lessen the symptoms and to prevent the progression of organ damage.

Periodic fever syndromes

Periodic fever syndromes are autoinflammatory diseases. The majority present in infancy or childhood and are characterised by recurrent episodes of fever and systemic inflammation that occur in the absence of autoantibody production or identifiable infection. The best recognised disorders include CAPS, FMF, TRAPS and MKD. Understanding the molecular pathogenesis of these disorders provides unique insights into the regulation of innate immunity. Diagnosis relies on clinical acumen and is supported by genetic testing. With the exception of FMF, which is prevalent in populations originating from the Mediterranean, these syndromes are rare and easily overlooked in the investigation of recurrent fevers. Disease severity varies from mild to life threatening, and one of the most feared complications is AA amyloidosis. Effective therapies are available for many of the syndromes, including colchicine, IL-1 blockade and anti-TNF therapies, and there is an increasing interest in blocking interferon pathways.

Gene mutations and clinical phenotypes in 15 Chinese children with cryopyrin-associated periodic syndrome (CAPS)

The aim of our study is to explore the features of clinical manifestations and genetic mutations in Chinese CAPS patients. Fifteen confirmed patients with CAPS were enrolled. The onset time ranges from 2 days after birth to 6 years and 1 month. Recurrent urticaria rash (93.3%) with fever (100%) were two dominant characteristics of these patients that were presented as either acute or chronic process. Systemic involvements were found in all patients except for one with only rash and fever. The top three symptoms were fever (100%), rash (93.3%) and myalgia (76%). Other clinical manifestations include arthritis (11 cases), lung involvement (seven cases), optical dysfunction (seven cases), nerve deafness (six cases), nervous system involvement (five cases), hepatomegaly, splenomegaly and lymphadenectasis (five cases). Also, four patients had heart involvement and one patient suffered kidney involvement. The laboratory inflammation index such as leukocyte counts, platelet counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum amyloid A (SAA) and fibrinogen (FIB) increased significantly at initial stage, but decreased after therapy. As for gene mutation detection, Twelve out of 15 patients were confirmed with mutation in NLRP3, including 11 mutant site: c1789A<G, c.1703T<A, c.913G<A, c.1710G<C, c.1057G<T, c.2335C<T, c.932TvC, c.296G<C, c.663C<T, t.1702T<A, 299G<A. Mutation sites c.1703T<A, c.2335C<T, c.296G<C, c.663C<T, and 299G<A were newly identified. The association between gene mutation and clinical manifestation shows that D305N was highly associated with severe organs involvements, and therefore, the time of therapy and regimen were critical for the prognosis of disease. As the largest cohort study of Chinese CAPS patients, we confirmed that all patients presented typical clinical manifestations, identified five new mutation sites on NLRP3 and analyzed the correlation between the genotypes and phenotypes. We also raise concerns for one case with serious conditions that only had two nonsense mutations (c.663C<T and t.1702T<A) detected.

[Cryopyrin-associated periodic syndromes]

Cryopyrin-associated periodic syndromes (CAPS) are linked to one single gene mutations, however they are associated with 3 syndromes, which are, from the mildest to the most severe phenotype familial cold urticaria, Muckle-Wells syndrome and chronic, infantile, neurologic, cutaneous, articular (CINCA) syndrome also called neonatal-onset multisystem inflammatory disease (NOMID). Autosomic dominant inheritance is present in most cases but in CINCA/NOMID syndrome where neomutations are more common. Mutations in the gene encoding cryopyrin, NLRP3, are associated with deregulation of caspase-1 activity, excessive interleukin-1 production and an autoinflammatory syndrome, which in familial cold urticaria and Muckle-Wells syndrome may be triggered or worsened by exposure to coldness. More and more mutations are described and even somatic mutations that can explain some clinical signs beginning in adulthood. Patients disclose a pseudo-urticarial rash, arthralgia, headaches, sometimes fever, biological inflammation but also, in severe forms of the disease, neurologic inflammation with central deafness, ophthalmologic inflammation, chronic meningitis. Some CINCA/NOMID patients also develop growth cartilage pseudo-tumoral hypertrophy. Natural disease history is usually benign in familial cold urticarial but severe in the other forms, particularly regarding neuro-sensorial involvement. In addition, secondary AA amyloidosis may develop in all forms in the absence of control of chronic inflammation. Anti-interleukin-1 treatment with anakinra, rilonacept or canakinumab induces in most cases complete remission, however sequelae may be present, particularly if central deafness or cartilage bone hypertrophy have already developed. This treatment is also important to prevent secondary amyloidosis or stabilize and even sometimes allow improvement of amyloidosis lesions.

A web-based collection of genotype-phenotype associations in hereditary recurrent fevers from the Eurofever registry

Background

Hereditary recurrent fevers (HRF) are a group of rare monogenic diseases leading to recurrent inflammatory flares. A large number of variants has been described for the four genes associated with the best known HRF, namely MEFV, NLRP3, MVK, TNFRSF1A. The Infevers database (http://fmf.igh.cnrs.fr/ISSAID/infevers) is a large international registry collecting variants reported in these genes. However, no genotype-phenotype associations are provided, but only the clinical phenotype of the first patient(s) described for each mutation. The aim of this study is to develop a registry of genotype-phenotype associations observed in patients with HRF, enrolled and validated in the Eurofever registry.

Results

Genotype-phenotype associations observed in all the patients with HRF enrolled in the Eurofever registry were retrospectively analyzed. For autosomal dominant diseases (CAPS and TRAPS), all mutations were individually analyzed. For autosomal recessive diseases (FMF and MKD), homozygous and heterozygous combinations were described. Mean age of onset, disease course (recurrent or chronic), mean duration of fever episodes, clinical manifestations associated with fever episodes, atypical manifestations, complications and response to treatment were also studied.

Data observed in 751 patients (346 FMF, 133 CAPS, 114 MKD, 158 TRAPS) included in the Eurofever registry and validated by experts were summarized in Tables. A total of 149 variants were described: 46 TNFRSF1A and 27 NLRP3 variants, as well as various combinations of 48 MVK and 28 MEFV variants were available.

Conclusions

We provide a potentially useful tool for physicians dealing with HRF, namely a registry of genotype-phenotype associations for patients enrolled in the Eurofever registry. This tool is complementary to the Infevers database and will be available at the Eurofever and Infevers websites.

Monogenic autoinflammatory diseases: General concepts and presentation in adult patients

Monogenic autoinflammatory diseases (AIFD) are rare disorders characterized by an uncontrolled increase of the systemic inflammatory response, which is caused by mutations in genes involved in inflammatory pathways. Over the last few years, new genes and proteins responsible for new monogenic AIFD have been identified and a substantial improvement in their treatment has been achieved. Monogenic AIFD manifestations typically begin during childhood, but they can also occur in adults. Compared to pediatric patients, adults usually present with a less severe disease and fewer long-term complications. In addition, patients with adult-onset disease carry low-penetrance mutations more often than pathogenic variants. A late-onset of AIFD may be occasionally associated with the presence of somatic mutations. In this study, we review the most frequent monogenic AIFD, and others recently described, which may occur during adulthood.

Real-World Experience and Impact of Canakinumab in Cryopyrin-Associated Periodic Syndrome: Results From a French Observational Study

OBJECTIVE

The ENVOL study was designed to assess the psychosocial impact of disease and therapy in a French cohort of cryopyrin-associated periodic syndromes (CAPS) patients (and caregivers) treated with canakinumab.

METHODS

The ENVOL study was a multicenter, observational study of CAPS patients given ≥1 canakinumab dose. Data were collected before treatment, at 6 and 12 months afterward, and at the last visit. Patients and caregivers completed questionnaires assessing changes from the 12 months of pretreatment to 12 months prior to interview. Data were analyzed retrospectively.

RESULTS

The study included 10 physicians and 68 patients (53 adults, 15 children). Sixty-five patients (95.6%) were still receiving canakinumab at the last visit (median 5 years after starting therapy). The mean ± SD score for patient-reported general health increased from 7 ± 2.9 before canakinumab to 2.7 ± 2.7 after treatment (P < 0.001). Physical and emotional symptoms resolved or improved in a substantial proportion of patients, including bodily pain (38 of 46 patients), fever (32 of 39), skin disease (35 of 41), fatigue (31 of 47), self-confidence (29 of 46), and energy (34 of 47). Social activity, relationships, sexuality, and energy measures improved in >40% of respondents. Caregivers spent a median of 3 versus 0.5 hours/week on care in the 12 months of pretreatment versus 12 months prior to interview (P < 0.001). Following treatment, patients required fewer consultations with general practitioners (mean ± SD per patient per year: 5.2 ± 7.4 versus 8.5 ± 7.2 pretreatment), internists/rheumatologists/dermatologists (2.0 ± 2.1 versus 3.7 ± 3.9), and pediatricians (1.8 ± 1.5 versus 4.4 ± 4.2).

CONCLUSION

Long-term treatment with canakinumab achieves a highly relevant improvement in the physical, emotional, and social lives of patients with CAPS, accompanied by a marked reduction in support required from caregivers and in health care consultations.

Brief Report: Late-Onset Cryopyrin-Associated Periodic Syndrome Due to Myeloid-Restricted Somatic NLRP3 Mosaicism

OBJECTIVE

Gain-of-function NLRP3 mutations cause cryopyrin-associated periodic syndrome (CAPS), with gene mosaicism playing a relevant role in the pathogenesis. This study was undertaken to characterize the genetic cause underlying late-onset but otherwise typical CAPS.

METHODS

We studied a 64-year-old patient who presented with recurrent episodes of urticaria-like rash, fever, conjunctivitis, and oligoarthritis at age 56 years. DNA was extracted from both unfractionated blood and isolated leukocyte and CD34+ subpopulations. Genetic studies were performed using both the Sanger method of DNA sequencing and next-generation sequencing (NGS) methods. In vitro and ex vivo analyses were performed to determine the consequences that the presence of the variant have in the normal structure or function of the protein of the detected variant.

RESULTS

NGS analyses revealed the novel p.Gln636Glu NLRP3 variant in unfractionated blood, with an allele frequency (18.4%) compatible with gene mosaicism. Sanger sequence chromatograms revealed a small peak corresponding to the variant allele. Amplicon-based deep sequencing revealed somatic NLRP3 mosaicism restricted to myeloid cells (31.8% in monocytes, 24.6% in neutrophils, and 11.2% in circulating CD34+ common myeloid progenitor cells) and its complete absence in lymphoid cells. Functional analyses confirmed the gain-of-function behavior of the gene variant and hyperactivity of the NLRP3 inflammasome in the patient. Treatment with anakinra resulted in good control of the disease.

CONCLUSION

We identified the novel gain-of-function p.Gln636Glu NLRP3 mutation, which was detected as a somatic mutation restricted to myeloid cells, as the cause of late-onset but otherwise typical CAPS. Our results expand the diversity of CAPS toward milder phenotypes than previously reported, including those starting during adulthood.

Muckle-Wells syndrome: clinical perspectives

Muckle–Wells syndrome (MWS) is a rare autoinflammatory disorder. It is due to NLRP3 gene mutations, responsible for excessive caspase-1 activation and interleukin 1β processing. MWS is the intermediate phenotype of severity of cryopyrin-associated periodic syndrome. Urticarial rash, conjunctivitis, recurrent fever, arthralgia, and fatigue are the main clinical manifestations of MWS. Yet, sensorineural hearing loss and renal amyloidosis can occur after long term evolution. Patients’ quality of life has been drastically improved with the advent of IL-1 inhibitors. This review reports recent findings in MWS, particularly genotype/phenotype correlation, and discusses the clinical perspectives of this disease in a time of efficient treatment.

No shortcuts: new findings reinforce why nuance is the rule in genetic autoinflammatory syndromes

PURPOSE OF REVIEW

Practitioners dazed by the evolving concept of autoinflammation are in good company. Despite the clinical challenges autoinflammatory patients present, their study has been fundamental to our understanding of basic human inflammation. This review will focus on the ways in which recent discoveries in genetically mediated autoinflammation broaden and refine the concept.

RECENT FINDINGS

Major developments in pyrin inflammasome biology, defective ubiquitination, and the hyperferritinemic syndromes will be highlighted.

SUMMARY

We offer a brief discussion of discordance, convergence, genotype, and phenotype in autoinflammation. Additionally, we introduce the concepts of mutation dose effect and hybrid nomenclature. Overall, we hope to provide an update on developments in the field of autoinflammation, some conceptual tools to help navigate the rising tide of discovery, and some encouragement that keeping up with developments in autoinflammation is both exciting and necessary.

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.

Autoinflammation in pyoderma gangrenosum and its syndromic form (pyoderma gangrenosum, acne and suppurative hidradenitis)

BACKGROUND

Pyoderma gangrenosum (PG) is a rare skin disease characterized clinically by ulcers with undermined borders, and histologically by neutrophil-rich infiltrates. PG may occur alone, in syndromic forms or associated with systemic diseases, such as inflammatory bowel disease and haematological or rheumatological disorders.

OBJECTIVES

To determine a specific genetic background related to autoinflammation for PG.

METHODS

We assessed autoinflammation by evaluating the cytokine profile and genes involved in classic autoinflammatory diseases in 13 patients with PG and in seven patients with the syndromic form, known as PASH (pyoderma gangrenosum, acne and suppurative hidradenitis).

RESULTS

In skin samples, the expression of interleukin (IL)-1β and its receptors, IL-17 and its receptor, and tumour necrosis factor-α and its receptors were significantly higher in both PG (P = 0·001) and in PASH (P < 0·001) than in controls. The chemokines IL-8; chemokine (C-X-C motif) ligand 1/2/3; chemokine (C-X-C motif) ligand 16; and RANTES (regulated on activation, normal T-cell-expressed and secreted) were also overexpressed. Cases of PG and PASH showed mutations in the autoinflammatory genes MEFV, NLRP3, NLRP12, NOD2, LPIN2 and PSTPIP1.

CONCLUSIONS

Overexpression of cytokines/chemokines, along with genetic changes, supports the hypothesis that PG and its syndromic form, PASH, are a spectrum of polygenic autoinflammatory conditions.

Monogenic Autoinflammatory Diseases with Mendelian Inheritance: Genes, Mutations, and Genotype/Phenotype Correlations

Autoinflammatory diseases (AIDs) are a genetically heterogeneous group of diseases caused by mutations of genes encoding proteins, which play a pivotal role in the regulation of the inflammatory response. In the pathogenesis of AIDs, the role of the genetic background is triggered by environmental factors through the modulation of the innate immune system. Monogenic AIDs are characterized by Mendelian inheritance and are caused by highly penetrant genetic variants in single genes. During the last years, remarkable progress has been made in the identification of disease-associated genes by using new technologies, such as next-generation sequencing, which has allowed the genetic characterization in undiagnosed patients and in sporadic cases by means of targeted resequencing of a gene panel and whole exome sequencing. In this review, we delineate the genetics of the monogenic AIDs, report the role of the most common gene mutations, and describe the evidences of the most sound genotype/phenotype correlations in AID.

Neurological outcome of patients with cryopyrin-associated periodic syndrome (CAPS)

Background

To assess the neurological involvement and outcome, including school and professional performances, of adults and children with cryopyrin-associated periodic syndrome (CAPS).

Methods

In this observational study, patients with genetically proven CAPS and followed in the national referral centre for autoinflammatory diseases at Bicêtre hospital were assessed. Neurological manifestations, CSF data and MRI results at diagnosis and during follow-up were analyzed.

Results

Twenty-four patients (15 adults and 9 children at diagnosis) with CAPS were included. The median age at disease onset was 0 year (birth) [range 0–14], the median age at diagnosis was 20 years [range 0–53] and the mean duration of follow-up was 10.4 ± 2 years. Neurological involvement at diagnosis, mostly headaches and hearing loss, was noted in 17 patients (71%). Two patients of the same family had abnormal brain MRI. A439V mutation is frequently associated with a non-neurological phenotype while R260W mutation tends to be associated with neurological involvement. Eleven adult patients (61%) and 3 children (50%) underwent school difficulties.

Conclusion

Neurological involvement is frequent in patients with CAPS and the majority of patients presented difficulties in school performances with consequences in the professional outcome during adulthood. Further studies in larger cohorts of children with CAPS focusing in intellectual efficiency and school performances are necessary.

The NLRP3 and Pyrin Inflammasomes: Implications in the Pathophysiology of Autoinflammatory Diseases

Inflammasomes are multiprotein complexes that critically control different aspects of innate and adaptive immunity. Among them we could highlight the release of pro-inflammatory cytokines that induce and maintain the inflammatory response. Usually, inflammasomes result from oligomerization of a nucleotide-binding domain-like receptor (NLR) after sensing different pathogenic or endogenous sterile dangerous signals; however, other proteins such as absent in melanoma 2, retinoic acid-inducible gene I, or pyrin could also form inflammasome platforms. Inflammasome oligomerization leads to caspase-1 activation and the processing and release of the pro-inflammatory cytokines, such as interleukin (IL)-1β and IL-18. Mutations in different inflammasomes are causative for multiple periodic hereditary syndromes or autoinflammatory diseases, characterized by acute systemic inflammatory flares not associated with infections, tumors, or autoimmunity. This review focuses on germline mutations that have been described in cryopyrin-associated periodic syndrome (CAPS) for NLRP3 or in familial Mediterranean fever (FMF) and pyrin-associated autoinflammation with neutrophilic dermatosis (PAAND) for MEFV. Besides the implication of inflammasomes in autoinflammatory syndromes, these molecular platforms are involved in the pathophysiology of different illnesses, including chronic inflammatory diseases, degenerative processes, fibrosis, or metabolic diseases. Therefore, drug development targeting inflammasome activation is a promising field in expansion.

Interleukin-1 as a mediator of fatigue in disease: a narrative review

Fatigue is commonly reported in a variety of illnesses, and it has major impact on quality of life. Previously, it was thought that fatigue originates in the skeletal muscles, leading to cessation of activity. However, more recently, it has become clear that the brain is the central regulator of fatigue perception. It has been suggested that pro-inflammatory cytokines, especially interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β), play a prominent role in the development of central fatigue, and several studies have been performed to elucidate the connection between inflammation and these central processes.In this narrative review, mechanisms of action of IL-1 are described, with special attention to its effect on the central nervous system. In addition, we present a summary of studies that (i) investigated the relationship between circulating IL-1α and IL-1β and fatigue severity and/or (ii) evaluated the effect of inhibiting IL-1 on fatigue. We aim to improve the understanding of fatigue in both inflammatory and non-inflammatory illnesses, which could help develop strategies to treat fatigue more effectively.Reviewing the studies that have been performed, it appears that there is a limited value of measuring circulating IL-1. However, inhibiting IL-1 has a positive effect on severe fatigue in most studies that have been conducted.

Muckle-Wells syndrome in Chinese patients: a single center case series

Muckle-Wells syndrome (MWS) is a rare autoinflammatory disease. This study aimed to report the clinical features and gene variations of the first case series of MWS patients in Chinese population. Four Han Chinese patients were diagnosed with MWS and followed up at our adult clinic for autoinflammatory diseases. All relevant phenotypes and genotypes were collected. All patients were adult male. The median age of disease onset was 4.5 years, and one patient had adult-onset disease. No positive family history was observed. All patients had a remittent disease course. The duration of fever attacks ranged from 0.5 to 7 days. Skin rashes were present in all patients. The other manifestations included polyarthralgia/arthritis (n = 3), oral ulcers (n = 2), conjunctivitis (n = 2), myalgia (n = 2), headache (n = 2), pharyngitis (n = 1), abdominal pain (n = 1), severe sensorineural hearing loss (n = 1), and chronic meningitis with communicating hydrocephalus (n = 1). None of the patients showed evidence of renal amyloidosis. Each patient carried a heterozygous mutation in an NLRP3 gene, including D29V, V70M, T348M, and Q703K, respectively. D29V and V70M variants were novel mutations in exon 1 of NLRP3. All patients had good response to corticosteroids. Our study suggests that MWS could be identified in Chinese population. Our finding of novel mutations in NLRP3 may expand the diversity of MWS.

Chronic Infantile Neurological Cutaneous and Articular (CINCA) syndrome: a review

Introduction

The Chronic Infantile Neurological Cutaneous and Articular (CINCA, or Neonatal-onset multisystem inflammatory disease NOMID) is a rare autoinflammatory disease identified in 1987 by Prieur et al., typically characterized by the triad of skin rash, arthropathy and central nervous system manifestations. It represents the most severe phenotype of the cryopyrin-associated periodic syndrome (CAPS).

Clinical description and etiology

The syndrome is due to autosomal dominant gain of function mutations in NLRP3, which encodes a key component of the innate immunity that regulates the activation and secretion of interleukin (IL)-1β. From the first days of life, patients display an urticarial rash in association with chronic inflammation with a typical facies featured by frontal bossing and saddle back nose. The CNS manifestations include chronic aseptic meningitis leading to brain atrophy, mental delay and sensorineural hearing loss. Chronic polyarthritis and alteration of the growth cartilage also may be present. CINCA/NOMID diagnosis is made clinically, based on the presence of characteristic features. The detection of NLRP3 mutations is diagnostic in 65–70% of cases. Indeed, up to 40% of affected patients are negative for germline NLRP3 mutations and several subjects are carriers of somatic mosaicism. Due to the pivotal role of Cryopyrin in the control of Caspase-1 activation and the massive secretion of active IL-1β observed in cryopyrin-mutated individuals, anti-IL1 treatment represents the standard therapy.

Conclusion

Prognosis of CINCA/NOMID syndrome has been changed by the availability of anti-IL1 drugs. Nowadays, the use of anti-IL-1 drugs has sensibly reduced the risk of developing main complications such as severe intellectual disability, hearing-loss and amyloidosis, if treatment is started early on.

Autoinflammatory diseases in adults. Clinical characteristics and prognostic implications

Autoinflammatory diseases are clinical conditions with inflammatory manifestations that present in a periodic or persistent manner and are caused by acquired or hereditary disorders of the innate immune response. In general, these diseases are more common in childhood, but cases have been reported in adults and are therefore important for all specialists. There are few references on these diseases in adults due to their low prevalence and underdiagnosis. The aim of this study is to review the scientific literature on these disorders to systematise their clinical, prognostic and treatment response characteristics in adults.

AAO: Autoimmune and Autoinflammatory (Disease) in Otology: What is New in Immune-Mediated Hearing Loss

OBJECTIVES

Autoinflammatory diseases are a family of immune-mediated, rare diseases, some of which, exhibit sensorineural hearing loss (SNHL), suggesting potentially similar mechanisms of molecular pathogenesis between autoinflammatory-mediated hearing loss and autoimmune inner ear disease (AIED) may exist. The purpose of this review is to compare the clinical features of autoimmune and autoinflammatory diseases that affect hearing, discuss the limitations of our knowledge, and highlight potential new disease mechanisms and therapeutics.

DATA SOURCES

Pubmed Literature Review; Google Scholar Literature review.

REVIEW METHODS

A focused comparison of AIED with a number of autoinflammatory diseases that manifest with sensorineural hearing loss was performed. The pathogenesis of these diseases is reviewed in the context of the innate and adaptive immune system, cytokine expression and genetic polymorphisms.

RESULTS

AIED, since first described by Cogan and Lehnhardt and first clinically characterized by McCabe, has remained an enigmatic disease, with limited advances in both new diagnostics and new therapeutics. Since the discovery of autoinflammatory diseases, a number of systemic autoimmune diseases have either been re-classed as autoinflammatory diseases or identified to have features of autoinflammatory disease.

CONCLUSION

AIED has clinical features of both autoimmune and autoinflammatory disease. It is critical that autoinflammatory diseases be correctly identified, as failure to do so may result in systemic amyloidosis and kidney damage.

Systemic and organ involvement in monogenic autoinflammatory disorders: a global review filtered through internists' lens

Monogenic autoinflammatory disorders (AIDs) are rare diseases driven by cytokine-mediated extraordinary sterile inflammation that results from the activation of innate immune pathways. The clinical hallmark of these diseases is the recurrence of stereotyped episodes of systemic- and organ-specific inflammation; the most common systems involved being the skin, musculoskeletal system, gastrointestinal tract, and central nervous system. The autoinflammatory disorders may have a profound impact on the quality of life of the affected patients, and a delayed diagnosis may lead to severe complications, the most dreadful of which is AA-Amyloidosis. This review gives an overview on the four main AIDs, namely familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, cryopyrinopathies, and mevalonate kinase deficiency, focusing on their clinical phenotype in adults and differential diagnosis, suggesting a diagnostic algorithm, and reviewing the available treatments.

Muckle-Wells Syndrome: A Case Report with an NLRP3 T348M Mutation

Autoinflammatory syndromes are a recently described group of conditions caused by mutations in multiple genes that code for proteins of the innate immune system. Cryopyrin-associated periodic syndromes are autoinflammatory diseases comprising three clinically overlapping disorders: familial cold urticaria syndrome, Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease. MWS is characterized by a moderate phenotype with fever, rash, arthralgia, conjunctivitis, sensorineural deafness, and potentially life-threatening amyloidosis. We report a 5-year-old girl with MWS that manifested as a recurrent skin rash without fever episodes or intracranial hypertension with papilledema. Genetic analysis revealed a T348M mutation of the NLRPR 3 gene in the patient and her mother. She was successfully treated with the interleukin-1β antagonist receptor anakinra.

Cryopyrin-associated periodic syndrome in Australian children and adults: Epidemiological, clinical and treatment characteristics

AIM

Cryopyrin-associated periodic syndromes (CAPS) encapsulate three auto-inflammatory conditions, ranging in severity from mild (familial cold auto-inflammatory syndrome: FCAS), moderate (Muckle-Wells syndrome: MWS) and severe (neonatal onset multi-inflammatory disorder: NOMID). We aimed to describe the epidemiology, clinical features and outcomes of Australian children and adults with CAPS.

METHODS

Patients were identified and clinical data collected through a questionnaire sent during 2012-2013 to clinicians reporting to the Australian Paediatric Surveillance Unit and subscribing to the Australasian Societies for Allergy/Immunology, Rheumatology and Dermatology.

RESULTS

Eighteen cases of CAPS were identified (8 NOMID; 8 MWS, 2 FCAS); 12 in children <18 years of age. The estimated population prevalence of CAPS was 1 per million persons. Diagnostic delay was frequent, particularly in those with milder phenotypes (median diagnostic delay in MWS/FCAS 20.6 years compared with NOMID 2.1 years; P = 0.04). Common presenting features included urticaria (100%), periodic fever (78%), arthralgia (72%) and sensorineural hearing loss (61%). Almost all (90%) MWS patients had a family member similarly affected compared with none in the NOMID group (P = 0.004). A significant proportion of patients on anti-interleukin (IL)-1 therapy (n = 13) no longer had systemic inflammation. Only 50% with sensorineural hearing loss had hearing restored on anti-IL-1 therapy.

CONCLUSIONS

Although CAPS are rare, patients often endured prolonged periods of systemic inflammation. This is despite almost all MWS patients having family members with similar symptoms and children with NOMID presenting with chronic infantile urticaria associated with multi-system inflammation. Hearing loss in NOMID/MWS was frequent, and reversible in only 50% of cases.

Induction of Myeloid-Derived Suppressor Cells in Cryopyrin-Associated Periodic Syndromes

Cryopyrin-associated periodic syndromes (CAPS) are caused by mutations in the NLRP3 gene leading to overproduction of IL-1β and other NLRP3 inflammasome products. Myeloid-derived suppressor cells (MDSCs) represent a novel innate immune cell subset capable of suppressing T-cell responses. As inflammasome products were previously found to induce MDSCs, we hypothesized that NLRP3 inflammasome-dependent factors induce the generation of MDSCs in CAPS. We studied neutrophilic MDSCs, their clinical relevance, and MDSC-inducing factors in a unique cohort of CAPS patients under anti-IL-1 therapy. Despite anti-IL-1 therapy and low clinical disease activity, CAPS patients showed significantly elevated MDSCs compared to healthy controls. MDSCs were functionally competent, as they suppressed polyclonal T-cell proliferation, as well as Th1 and Th17 responses. In addition, MDSCs decreased monocytic IL-1β secretion. Multiplex assays revealed a distinct pattern of MDSC-inducing cytokines, chemokines, and growth factors. Experimental analyses demonstrated that IL-1 cytokine family members and autoinflammation-associated alarmins differentially induced human MDSCs. Increased MDSCs might represent a novel autologous anti-inflammatory mechanism in autoinflammatory conditions and may serve as a future therapeutic target.

Genetically defined autoinflammatory diseases

Autoinflammatory diseases are hyperinflammatory, immune dysregulatory conditions that typically present in early childhood with fever and rashes and disease-specific patterns of organ inflammation. This review provides a historic background of autoinflammatory disease research, an overview of the currently genetically defined autoinflammatory diseases, and insights into treatment strategies derived from understanding of the disease pathogenesis. The integrative assessment of autoinflammatory conditions led to the identification of innate pro-inflammatory cytokine 'amplification loops' as the cause of the systemic and organ-specific disease manifestations, which initially centered around increased IL-1 production and signaling. More recently, additional innate pro-inflammatory cytokine amplification loops resulting in increased Type I IFN, IL-17, IL-18, or IL-36 signaling or production have led to the successful use of targeted therapies in some of these conditions. Clinical findings such as fever patterns, type of skin lesions, genetic mutation testing, and the prevalent cytokine abnormalities can be used to group autoinflammatory diseases.

Clinical Characteristics of Patients Carrying the Q703K Variant of the NLRP3 Gene: A 10-year Multicentric National Study

Objective.

The aim of our study was to analyze the clinical and functional effect of the p.Q703K (p. Q705K, c. 2107C>A) variant of the NLRP3 gene in a population of patients screened for suspected cryopyrin-associated periodic syndrome (CAPS).

Methods.

Since 2002, 580 patients underwent molecular analysis for NLRP3. Data on clinical presentation, response to treatment, and longterm followup were collected using a uniform questionnaire. The pattern of cytokine secretion after lipopolysaccharide stimulation from isolated monocytes was analyzed in 3 patients carrying the p.Q703K variant and 1 patient with a chronic infantile neurologic, cutaneous, articular syndrome phenotype carrying both the p.M406I and p.Q703K, and compared with 7 patients with CAPS with sure pathogenic variants and 6 healthy controls.

Results.

The p.Q703K variant was found in 57 screened patients with an overall allelic frequency of 5%. The frequency in normal controls was 5.5%. Clinical data at the moment of molecular analysis and at followup were available in 36 patients. Two patients displayed additional mutations of NLRP3. The mean followup was 2.5 years. Thirteen patients (39%) had a final diagnosis different from the original suspicion of CAPS. The remaining 21 patients displayed a mild phenotype mainly characterized by recurrent episodes of urticarial rash and arthralgia. Only 8 patients were treated with anti-interleukin (IL)-1 treatment, with a complete response in 5 patients. The pattern of secretion of IL-1β and other cytokines (IL-6 and IL-1 receptor antagonist) in patients did not display the aberrancies observed in patients with CAPS and was similar to that observed in healthy controls.

Conclusion.

The present study confirms the weak clinical and functional effect of the p.Q703K variant.

Neurology of the cryopyrin-associated periodic fever syndrome

BACKGROUND AND PURPOSE

The cryopyrin-associated periodic fever syndrome (CAPS) is an autosomal dominant autoinflammatory disorder caused by mutations in the NLRP3 gene and is typified by recurrent episodes of systemic inflammation resulting in fever, urticarial rash and arthralgia. In addition to these systemic aspects, CAPS has multiple neurological manifestations. The largest case series to date is presented focusing on the neurological features of this disorder.

METHODS

The case histories of a cohort of 38 UK patients with genetically proven CAPS who were treated with interleukin 1β (IL-1β) inhibition as part of a national treatment programme and underwent detailed neurological assessment were reviewed.

RESULTS

Across the entire disease course neurological manifestations were present in 95% of patients; 84% had some form of headache; 66% sensorineural hearing loss; 60% myalgia; 34% papilloedema and 26% optic atrophy. Patients with the T348M mutation tended to have a more severe neurological phenotype with an earlier age of onset. Four patients had cerebrospinal fluid examination, three of whom had evidence of aseptic meningitis. There was a marked response to IL-1β inhibition, which has revolutionized management of these patients (29/32 patients with headache responding).

CONCLUSION

Neurological symptoms are extremely common in CAPS and these results highlight the importance of increasing awareness amongst neurologists, particularly as highly effective therapies are available.

Autoinflammatory Syndromes in Children

Systemic autoinflammatory diseases are rare disorders of innate immunity which usually present in childhood with recurrent or continuous attacks of fever and systemic inflammation. The discovery of the genetic defect underlying Familial Mediterranean fever in 1997 has proved exceptionally informative about the innate immune system and the regulation of pro inflammatory cytokines particularly IL-1. Although extremely rare, systemic autoinflammatory diseases are important to recognise as many can now be completely controlled by long term drug therapies. Diagnosis relies on clinical suspicion followed by genetic testing. This review will focus on the main systemic autoinflammatory diseases.

Basic Characteristics of Adults with Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Adenopathy Syndrome in Comparison with the Typical Pediatric Expression of Disease

Autoinflammatory diseases are caused by inflammasome dysregulation leading to overproduction of proinflammatory cytokines and a pathological delay in the inflammation switching off. The progress of cellular biology has partially clarified pathogenic mechanisms behind monogenic autoinflammatory diseases, whereas little is known about the polygenic ones. Although the genetic susceptibility of periodic fever, aphthous stomatitis, pharyngitis, and adenopathy (PFAPA) syndrome is still obscure, the presence of overlapping symptoms with monogenic periodic fevers, the recurrence in family members, the important role played by dysregulated interleukin- (IL-) 1β secretion during flares, the overexpression of inflammasome-associated genes during attacks, and, last but not least, the therapeutic efficacy of IL-1β blockade strongly indicate a potential genetic involvement in its pathogenesis, probably linked with environmental factors. PFAPA syndrome has a typical inception in the pediatric age, but a delayed onset during adulthood has been described as well. Treatments required as well as effectiveness of tonsillectomy remain controversial, even if the disease seems to have a self-limited course mostly in children. The purpose of this review is to provide an overview of this complex polygenic/multifactorial autoinflammatory disorder in which the innate immune system undoubtedly plays a basic role.

The protean ocular involvement in monogenic autoinflammatory diseases: state of the art

Ocular involvement is frequent in the monogenic autoinflammatory disorders and generally occurs as spontaneously recurring inflammatory events at different ocular sites caused by the aberrant release of proinflammatory cytokines, mainly IL-1β. Over the past decade, we witnessed a significant growth of eye abnormalities associated with idiopathic granulomatous disorders, familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, mevalonate kinase deficiency, and cryopyrin-associated periodic syndrome. The pathogenetic mechanisms of these disorders have shown the evidence of disrupted cytokine signaling, but the explanation for the heterogeneous ocular involvement remains to be elucidated. We herein review the monogenic autoinflammatory disorders affecting the eye, describing their main clinical features with specific regard to the ocular involvement, which can lead to decreased visual acuity and even blindness, if the primary disorder is undetected or left untreated.

Autoinflammatory syndromes as causes of fever of unknown origin

The systemic autoinflammatory syndromes often present with recurrent fevers. They have proved exceptionally informative about the innate immune system. Although extremely rare, they are important to recognise, as many can now be completely controlled by long-term drug therapies. Diagnosis relies on clinical suspicion followed by genetic testing.

Expanding spectrum of neurologic manifestations in patients with NLRP3 low-penetrance mutations

Objective:

To evaluate the frequency of the cryoporin/NLRP3 low-penetrance mutations V198M and Q703K in patients who reported at least 2 symptoms compatible with cryopyrin-associated periodic syndromes (CAPS) and to characterize the phenotype in mutation-positive patients.

Methods:

The frequency of the V198M and Q703K mutations was investigated in a selected cohort of 108 patients from our neuroimmunology department. We describe the clinical, neurologic, immunologic, and neuroradiologic features of the mutation carriers.

Results:

Seventeen patients (16%) tested positive for either of the 2 mutations (V198M: n = 2; Q703K: n = 15). Eleven patients (65%) had severe headache syndromes. Six of these 11 patients were diagnosed with migraine. Nine patients (53%) had a concomitant diagnosis of multiple sclerosis (MS). In 3 patients, we identified additional family members with the respective mutation as well as the diagnosis of MS. Severe recurrent cranial nerve (CN) affection was the hallmark feature in 7 of the 8 (88%) non-MS mutation carriers. Brain MRI showed abnormalities in all but 2 patients (88%) and detected CN inflammation in 4 patients. Interleukin-6 was elevated in the CSF of 2 patients in the non-MS cohort during acute CAPS episodes with severe CNS inflammation. 5 of 9 treated patients (56%) responded to anti–interleukin-1 therapy.

Conclusion:

CAPS constitute rare but treatable and commonly misdiagnosed autoinflammatory syndromes. Our data expand the spectrum of CAPS-associated neurologic manifestations. They also broaden our concept of autoimmunity and autoinflammation by linking CAPS and MS.