Recovery from deafness in a patient with Muckle-Wells syndrome treated with anakinra

Cytokines and Inflammation in Meniere Disease

Meniere disease (MD) is a rare set of conditions associated with the accumulation of endolymph in the cochlear duct and the vestibular labyrinth with a decrease of endocochlear potential. It is considered a chronic inflammatory disorder of the inner ear with a multifactorial origin. The clinical syndrome includes several groups of patients with a core phenotype: sensorineural hearing loss, episodes of vertigo, and tinnitus with a non-predictable course. Genetic factors and the innate immune response seem to play a central role in the pathophysiology of the condition. Autoimmune MD should be diagnosed if a patient fulfills the diagnostic criteria for MD and one of the following autoimmune disorders: autoimmune thyroid disease, psoriasis, autoimmune arthritis, ankylosing spondylitis, or systemic lupus erythematosus. We summarize the evidence to support autoimmune MD as an endophenotype in bilateral MD associated with the allelic variant rs4947296 and nuclear factor-kappa B (NF-κB)-mediated inflammation, the role of cytokines (particularly interleukin-1β and tumor necrosis factor-α) in defining a subset of patients with autoinflammation, and the potential role of cytokines as biomarkers to distinguish between patients with MD and vestibular migraine. Finally, we also introduce a list of potential drugs that could regulate the immune response in MD with potential for repurposing in clinical trials.

Biologics for Immune-Mediated Sensorineural Hearing Loss

Immune-mediated hearing losses include autoimmune inner ear disease, sudden sensorineural hearing loss, and Meniere's disease. Standard therapy for an acute decline in hearing is timely use of corticosteroids. Although 60% to 70% of patients are initially corticosteroid-responsive, that responsiveness is lost over time. In corticosteroid-resistant patients, increased expression of interleukin (IL)-1 is observed, and these patients may benefit from IL-1 inhibition. Autoinflammatory diseases are characterized by dysregulation of the innate immune response, clinically include sensorineural hearing loss, and benefit from IL-1 inhibition, thereby further establishing the relationship of IL-1 with immune-mediated sensorineural hearing loss.

Computational Modeling of NLRP3 Identifies Enhanced ATP Binding and Multimerization in Cryopyrin-Associated Periodic Syndromes

Cyropyrin-associated periodic syndromes (CAPS) are clinically distinct syndromes that encompass a phenotypic spectrum yet are caused by alterations in the same gene, NLRP3. Many CAPS cases and other NLRP3-autoinflammatory diseases (NLRP3-AIDs) are directly attributed to protein-coding alterations in NLRP3 and the subsequent dysregulation of the NLRP3 inflammasome leading to IL-1β-mediated inflammatory states. Here, we used bioinformatics tools, computational modeling, and computational assessments to explore the proteomic consequences of NLRP3 mutations, which potentially drive NLRP3 inflammasome dysregulation. We analyzed 177 mutations derived from familial cold autoinflammatory syndrome (FCAS), Muckle-Wells Syndrome (MWS), and the non-hereditary chronic infantile neurologic cutaneous and articular syndrome, also known as neonatal-onset multisystem inflammatory disease (CINCA/NOMID), as well as other NLRP3-AIDs. We found an inverse relationship between clinical severity and the severity of predicted structure changes resulting from mutations in NLRP3. Bioinformatics tools and computational modeling revealed that NLRP3 mutations that are predicted to be structurally severely-disruptive localize around the ATP binding pocket and that specific proteo-structural changes to the ATP binding pocket lead to enhanced ATP binding affinity by altering hydrogen-bond and charge interactions. Furthermore, we demonstrated that NLRP3 mutations that are predicted to be structurally mildly- or moderately-disruptive affect protein-protein interactions, such as NLRP3-ASC binding and NLRP3-NLRP3 multimerization, enhancing inflammasome formation and complex stability. Taken together, we provide evidence that proteo-structural mechanisms can explain multiple mechanisms of inflammasome activation in NLRP3-AID.

Novel mutation in the NRLP3 manifesting as an intermediate phenotype of cryopyrinopathies

Cryopyrin-associated periodic syndromes (CAPS) are a group of autoinflammatory diseases associated with NLRP3 gain of function mutations. CAPS associated mutations are found predominantly in exon 3. The objective of this study is to describe a new variant on NRLP3 gene and its phenotype. Case report description of a new NRLP3 pathogenic variant and literature case-based search through INFEVERS database. A 21-year old male who presented multiple tonic-clonic seizures on his 3rd day of life. At age 2, he had recurrent central facial palsy, high fever (40 °C), painful and persistent oral ulcers, abdominal pain, nausea and vomiting, and delayed neuropsychomotor development, with polyarthritis in wrists and knees. Over the years, several symptoms were observed: livedo reticularis, Raynaud's phenomenon, positive pathergy test, heat allodynia, extremely painful genital ulcers, and sporadic conjunctivitis. Laboratory studies revealed persistently elevated inflammatory markers and serum amyloid protein A (30 μg/l). The genetic panel for autoinflammatory diseases revealed heterozygous mutation in the NLRP3, (c.2068G > C, p.E690Q) with 0% of frequency in the general population. The patient denies rash and did not have frontal bossing or patellar overgrowth. We found a positive familial history on mother and brother, who carried the same mutation. The patient was started on canakinumab which controlled his symptoms. Currently, 241 missense variants in the NLRP3 have been described. We presented a new mutation in exon 3 of the NRLP3 gene in a patient that fulfills clinical criteria for CAPS who had complete clinical response to Canakinumab, supporting the idea that this mutation is pathogenic.

Off-Label studies on anakinra in dermatology: a review

Purpose: Anakinra (Kineret^®) is an interleukin-1 receptor antagonist (IL-1Ra) FDA approved for use in rheumatoid arthritis and in neonatal-onset multisystem inflammatory disease (NOMID). It has been used off-label for a variety of dermatologic conditions. A review of the available studies and cases of these off-label uses would be valuable to the dermatologist considering alternative treatments for these oftentimes poorly studied conditions.Materials and methods: The PubMed/MEDLINE, EMBASE, Scopus, and ClinicalTrials.gov databases were searched with the term 'anakinra.' Results were manually screened to identify published data on off-label uses of anakinra in dermatologic conditions and systemic conditions with prominent dermatologic manifestations.Results: Anakinra appears to show efficacy for numerous dermatologic conditions, with the strongest evidence for hidradenitis suppurativa, Bechet's disease, Muckle-Wells syndrome, and SAPHO syndrome. Case reports and case series data are available for numerous other dermatologic conditions.Conclusion: Anakinra is a potential option for patients with certain difficult-to-treat dermatologic diseases, given its relatively benign adverse effect profile and its effectiveness in a wide array of conditions. Overall, anakinra appears to be a promising option in the treatment of numerous dermatologic inflammatory conditions refractory to first line therapies, but further and higher-quality data is needed to clarify its therapeutic role.

Oxidative Stress and Inflammation Induced by Environmental and Psychological Stressors: A Biomarker Perspective

SIGNIFICANCE

The environment can elicit biological responses such as oxidative stress (OS) and inflammation as a consequence of chemical, physical, or psychological changes. As population studies are essential for establishing these environment-organism interactions, biomarkers of OS or inflammation are critical in formulating mechanistic hypotheses. Recent Advances: By using examples of stress induced by various mechanisms, we focus on the biomarkers that have been used to assess OS and inflammation in these conditions. We discuss the difference between biomarkers that are the result of a chemical reaction (such as lipid peroxides or oxidized proteins that are a result of the reaction of molecules with reactive oxygen species) and those that represent the biological response to stress, such as the transcription factor NRF2 or inflammation and inflammatory cytokines.

CRITICAL ISSUES

The high-throughput and holistic approaches to biomarker discovery used extensively in large-scale molecular epidemiological exposome are also discussed in the context of human exposure to environmental stressors.

FUTURE DIRECTIONS

We propose to consider the role of biomarkers as signs and to distinguish between signs that are just indicators of biological processes and proxies that one can interact with and modify the disease process. Antioxid. Redox Signal. 28, 852-872.

Resolution of unilateral sensorineural hearing loss in a pediatric patient with a severe phenotype of Muckle-Wells syndrome treated with Anakinra: a case report and review of the literature

Background

Muckle-Wells syndrome (MWS) is a rare auto-inflammatory disease characterized by the presence of recurrent urticaria, deafness and amyloidosis. Progressive sensorineural hearing loss (SNHL) is reported to occur in up to 85% of patients occurring in the second and third decades and as early as the first decade in patients with a more severe phenotype, thus potentially having a significant impact on a child’s development. IL-1 inhibitors, such as Anakinra, have been described to improve systemic inflammation, and stabilize or improve hearing status as well. However, complete resolution of hearing loss has been rarely reported. The objective of this article is to highlight the clinical presentation of a pediatric patient with a severe form of MWS and report on the complete resolution of SNHL with the use of Anakinra.

Case presentation

A 3-year-old boy was referred to our hospital to assess for the possibility of MWS given a history of hives and recurrent episodes of fever with a family history of MWS in his mother. Of note, the patient’s history was significant for conductive hearing loss, speech delay, as well as recurrent acute otitis media episodes. Genetic analysis was performed and diagnosis of MWS was confirmed due to the presence of a NLRP3 gene mutation. Further work-up demonstrated the presence of papilledema and elevation of systemic inflammatory markers for which Canakinumab was initiated. Despite initiation of this treatment, audiogram evaluation demonstrated a new right-sided SNHL. Lumbar puncture also revealed aseptic meningitis. Canakinumab was eventually discontinued and Anakinra initiated. Within 7 months of treatment with Anakinra at 5 mg/kg sc daily, resolution of the SNHL was observed. With further escalation of the Anakinra dose, there was also complete resolution of the aseptic meningitis.

Conclusions

Progressive hearing loss is a significant finding in patients with MWS. Early screening as well as initiation of Anakinra can lead to complete resolution of SNHL even in a patient with a severe spectrum of MWS. However, as this case demonstrates, longer treatment duration and higher doses of Anakinra may be required to achieve this.

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.

Current understanding of the pathogenesis of autoimmune inner ear disease: a review

BACKGROUND

Autoimmune inner ear disease (AIED) is a poorly understood form of sensorineural hearing loss that causes bilateral, asymmetric, progressive hearing loss, sometimes with vestibular symptoms, often associated with a systemic autoimmune disease, which is noteworthy as the only sensorineural loss responsive to medical therapy. Despite much research interest of the past 25 years, its aetiopathogenesis is still unproven.

OBJECTIVE OF REVIEW

To succinctly consolidate research and opinion regarding the pathogenesis of autoimmune inner ear disease, in ongoing efforts to elucidate the molecular and intracellular pathways that lead to inner ear damage, which may identify new targets for pharmacotherapy.

TYPE OF REVIEW

Systematic review

SEARCH STRATEGY

PubMed/MEDLINE search using key terms to identify articles published between January 1980 and Apr 2014. Additionally, any landmark works discussed in this body of literature were obtained and relevant information extracted as necessary.

EVALUATION METHOD

Inclusion criterion was any information from animal or human studies with information relevant to possible aetiopathogenesis of AIED. Studies that focused on diagnosis, ameliorating symptoms or treatment, without specific information relevant to mechanisms of immune-mediated injury were excluded from this work. Articles meeting the inclusion criteria were digested and summarised.

RESULTS

A proposed pathogenic mechanism of AIED involves inflammation and immune-mediated attack of specific inner ear structures, leading to an excessive Th1 immune response with vascular changes and tissue damage in the cochlea. Studies have identified self-reactive T cells and immunoglobulins, and have variously implicated immune-complex deposition, microthrombosis and electrochemical disturbances causing impaired neurosignalling in the pathogenesis of AIED. Research has also demonstrated abnormalities in the cytokine milieu in subjects with AIED, which may prove a target for therapy in the future.

CONCLUSION

Ongoing research is needed to further elucidate the aetiopathogenesis of AIED and discern between various mechanisms of tissue injury. Large-cohort clinical studies employing IL-1 receptor blockade are warranted to determine its potential for future therapy.

Musculoskeletal symptoms in patients with cryopyrin-associated periodic syndromes: a large database study

OBJECTIVE

To determine the type and frequency of musculoskeletal symptoms at onset and during followup of cryopyrin-associated periodic syndromes (CAPS).

METHODS

We retrospectively recorded the articular and muscular symptoms of patients with CAPS followed up in French hospitals. Data were presented as frequencies or the median (range), and patient groups were compared using chi-square test, Fisher's exact test, and Mann-Whitney test.

RESULTS

The study included 133 patients (33 children), 20 with familial cold autoinflammatory syndrome, 88 with Muckle-Wells syndrome, 22 with chronic infantile neurologic, cutaneous, articular syndrome, and 3 with unclassified CAPS. The median age was 35 years (range 0-78 years) at the time of the study, 1 year (range 0-41 years) at symptom onset, and 23 years (range 0-58 years) at diagnosis. The disease was sporadic in 17% of the patients. Cutaneous symptoms predominated at onset (77%), followed by articular symptoms (30%). The p.Thr348Met and p.Arg260Trp NLRP3 mutations were significantly associated with the presence and absence of articular symptoms at onset, respectively. During followup, 86% of the patients had musculoskeletal symptoms, 88% had arthralgia, and 58% had arthritis, but only 9% had joint destruction. Tendinopathies occurred in 21.5% of the patients, tender points in 16.5%, and myalgia in 33%. Only 3 patients had typical knee deformities. Radiographs were rarely obtained. Except for bone deformities, osteoarticular symptoms occurred at similar frequencies in the different CAPS phenotypes.

CONCLUSION

Joint manifestations were frequent in all CAPS phenotypes. Bone deformities were rare. Musculoskeletal manifestations varied within given families but tended to worsen over time.

The interleukin (IL)-1 cytokine family--Balance between agonists and antagonists in inflammatory diseases

The interleukin (IL)-1 family of cytokines comprises 11 members, including 7 pro-inflammatory agonists (IL-1α, IL-1β, IL-18, IL-33, IL-36α, IL-36β, IL-36γ) and 4 defined or putative antagonists (IL-1R antagonist (IL-1Ra), IL-36Ra, IL-37, and IL-38) exerting anti-inflammatory activities. Except for IL-1Ra, IL-1 cytokines do not possess a leader sequence and are secreted via an unconventional pathway. In addition, IL-1β and IL-18 are produced as biologically inert pro-peptides that require cleavage by caspase-1 in their N-terminal region to generate active proteins. N-terminal processing is also required for full activity of IL-36 cytokines. The IL-1 receptor (IL-1R) family comprises 10 members and includes cytokine-specific receptors, co-receptors and inhibitory receptors. The signaling IL-1Rs share a common structure with three extracellular immunoglobulin (Ig) domains and an intracellular Toll-like/IL-1R (TIR) domain. IL-1 cytokines bind to their specific receptor, which leads to the recruitment of a co-receptor and intracellular signaling. IL-1 cytokines induce potent inflammatory responses and their activity is tightly controlled at the level of production, protein processing and maturation, receptor binding and post-receptor signaling by naturally occurring inhibitors. Some of these inhibitors are IL-1 family antagonists, while others are IL-1R family members acting as membrane-bound or soluble decoy receptors. An imbalance between agonist and antagonist levels can lead to exaggerated inflammatory responses. Several genetic modifications or mutations associated with dysregulated IL-1 activity and autoinflammatory disorders were identified in mouse models and in patients. These findings paved the road to the successful use of IL-1 inhibitors in diseases that were previously considered as untreatable.

Targeting the NLRP3 inflammasome in chronic inflammatory diseases: current perspectives

The inflammasome is a molecular platform formed by activation of an innate immune pattern recognition receptor seed, such as NLRP3. Once activated, NLRP3 recruits the adapter ASC (apoptosis-related speck-like protein containing a caspase recruitment domain), which in turn recruits procaspase-1. Procaspase-1 autocatalyzes its cleavage and activation, resulting in maturation of the precursor forms of interleukin (IL)-1β and IL-18 into active proinflammatory cytokines and initiation of pyroptotic cell death. The NLRP3 inflammasome has been implicated in the pathogenesis of a wide variety of diseases, including genetically inherited autoinflammatory conditions as well as chronic diseases in which NLRP3 is abnormally activated. The NLRP3 inflammasome has been linked to diseases such as Alzheimer’s disease, atherosclerosis, metabolic syndrome, and age-related macular degeneration. In this review, we describe the NLRP3 inflammasome complex and its activation in disease, and detail the current therapies that modulate either the NLRP3 inflammasome complex itself or the two cytokines it is responsible for activating, ie, IL-1β and IL-18.

Muckle-Wells cryopyrinopathy: complex phenotyping and response to therapy in a new multiplex kindred

Muckle-Wells syndrome (MWS) is a member of the cryopyrin-associated periodic syndrome family of auto-inflammatory diseases, originally described as a triad of urticaria, sensorineural deafness and amyloidosis. IL-1 blockade is a proven therapy for MWS. The clinical, laboratory and genotypic characteristics of a novel kindred of five individuals with Muckle-Wells syndrome are described. Response to IL-1 blockade therapy in the proband was evaluated. All five affected family members experienced symptoms of multi-organ inflammation. Lead time between symptom onset and diagnosis was approximately 30 years in the proband. Fever was not a universal feature in all affected family members. Anti-IL-1 therapy in the proband resulted in improvements in patient-reported symptoms, inflammatory markers, auditory acuity and reversal of her infertility. Muckle-Wells syndrome is a rare, multisystem, auto-inflammatory syndrome. Delay in diagnosis prevents effective treatment. We propose reversal of infertility to be among the potential benefits of IL-1 inhibition in this disease.

Early efficacy trial of anakinra in corticosteroid-resistant autoimmune inner ear disease

BACKGROUND

Autoimmune inner ear disease (AIED) is a rare disease that results in progressive sensorineural hearing loss. Patients with AIED initially respond to corticosteroids; however, many patients become unresponsive to this treatment over time, and there is no effective alternative therapy for these individuals.

METHODS

We performed a phase I/II open-label, single-arm clinical trial of the IL-1 receptor antagonist anakinra in corticosteroid-resistant AIED patients. Given that the etiology of corticosteroid resistance is likely heterogeneous, we used a Simon 2-stage design to distinguish between an unacceptable (≤10%) and an acceptable (≥30%) response rate to anakinra therapy. Subjects received 100 mg anakinra by subcutaneous injection for 84 days, followed by a 180-day observational period.

RESULTS

Based on patient responses, the Simon 2-stage rule permitted premature termination of the trial after 10 subjects completed the 84-day drug period, as the target efficacy for the entire trial had been achieved. Of these 10 patients, 7 demonstrated audiometric improvement, as assessed by pure tone average (PTA) and word recognition score (WRS). In these 7 responders, reduced IL-1β plasma levels correlated with clinical response. Upon discontinuation of treatment, 3 subjects relapsed, which correlated with increased IL-1β plasma levels.

CONCLUSION

We demonstrated that IL-1β inhibition in corticosteroid-resistant AIED patients was effective in a small cohort of patients and that IL-1β plasma levels associated with both clinical hearing response and disease relapse. These results suggest that a larger phase II randomized clinical trial of IL-1β inhibition is warranted.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01267994.

FUNDING

NIH, Merrill & Phoebe Goodman Otology Research Center, and Long Island Hearing & Speech Society.

Somatic NLRP3 mosaicism in Muckle-Wells syndrome. A genetic mechanism shared by different phenotypes of cryopyrin-associated periodic syndromes

: Familial cold autoinflammatory syndrome, Muckle-Wells syndrome (MWS), and chronic, infantile, neurological, cutaneous and articular (CINCA) syndrome are dominantly inherited autoinflammatory diseases associated to gain-of-function NLRP3 mutations and included in the cryopyrin-associated periodic syndromes (CAPS). A variable degree of somatic NLRP3 mosaicism has been detected in ≈35% of patients with CINCA. However, no data are currently available regarding the relevance of this mechanism in other CAPS phenotypes.

OBJECTIVE

To evaluate somatic NLRP3 mosaicism as the disease-causing mechanism in patients with clinical CAPS phenotypes other than CINCA and NLRP3 mutation-negative.

METHODS

NLRP3 analyses were performed by Sanger sequencing and by massively parallel sequencing. Apoptosis-associated Speck-like protein containing a CARD (ASC)-dependent nuclear factor kappa-light chain-enhancer of activated B cells (NF-κB) activation and transfection-induced THP-1 cell death assays determined the functional consequences of the detected variants.

RESULTS

A variable degree (5.5-34.9%) of somatic NLRP3 mosaicism was detected in 12.5% of enrolled patients, all of them with a MWS phenotype. Six different missense variants, three novel (p.D303A, p.K355T and p.L411F), were identified. Bioinformatics and functional analyses confirmed that they were disease-causing, gain-of-function NLRP3 mutations. All patients treated with anti-interleukin1 drugs showed long-lasting positive responses.

CONCLUSIONS

We herein show somatic NLRP3 mosaicism underlying MWS, probably representing a shared genetic mechanism in CAPS not restricted to CINCA syndrome. The data here described allowed definitive diagnoses of these patients, which had serious implications for gaining access to anti-interleukin 1 treatments under legal indication and for genetic counselling. The detection of somatic mosaicism is difficult when using conventional methods. Potential candidates should benefit from the use of modern genetic tools.

A Retrospective Patient Chart Review and Survey in Patients with Cryopyrin-associated Periodic Syndromes Treated with Anakinra

Background: Cryopyrin-associated periodic syndromes (CAPS) is a group of rare autoinflammatory diseases. Little is known about the burden of disease, patients' views on treatment, and adverse events (AEs) with current therapy. Objectives: The main study objective was to quantify the patients' burden of disease in terms of flares and resource use and to characterize patient symptomatology and tolerability of treatment with anakinra. A secondary objective included comparing chart review and patient recall of symptoms and AEs. Methods: A retrospective medical chart review and concurrent online patient survey was conducted in four European countries. Data 12 months prior to initiation of/during anakinra treatment were entered into web-based case report forms by study groups. Results: Forty-two patients received/were receiving anakinra as primary treatment for at least 12 months. Patients experienced a 79.5% reduction in flares after commencing anakinra treatment. During the past 12 months on anakinra, four of five (80%) patients who recalled experiencing flares reported cancelling social activities and staying home as the most common courses of action. Most common AEs were injection site pain upon treatment initiation and weight gain. According to patient recall, 12 of 21 patients (57.1%) discontinued anakinra to enter another clinical trial; of the 12, eight (38%) specifically discontinued anakinra only for that reason, and four patients cited entering a clinical trial as one of many reasons for discontinuing anakinra. Conclusions: To our knowledge, this is the most comprehensive survey of patient experience with CAPS. Although improved, CAPS treatment remains suboptimal and a significant burden is placed upon patients, caregivers, and the healthcare system. With new agents available, it will be important to compare outcomes in patients using all therapeutic options.

Hearing loss in Muckle-Wells syndrome

OBJECTIVE

Muckle-Wells syndrome (MWS) is an inherited autoinflammatory disease characterized by fevers, rashes, arthralgia, conjunctivitis, and sensorineural hearing loss. In MWS, NLRP3 gene mutations are associated with excessive interleukin-1 release. The aims of this study were to determine the otologic characteristics of MWS, define trajectories of hearing loss, and explore the association with distinct NLRP3 genotypes.

METHODS

A prospective observational cohort study of children and adults diagnosed as having MWS was conducted at a single center. NLRP3 gene mutations were determined. Patients underwent standardized clinical, laboratory, and otologic assessments, including pure tone audiometry, vestibular organ testing, and tinnitus evaluation. Trajectories of hearing loss were defined for each genotype. The genotype-specific risk of progression of hearing loss was determined.

RESULTS

A total of 33 patients ages 3-75 years who were members of 5 families with 4 different NLRP3 gene mutations were included. The majority of patients (67%) experienced bilateral sensorineural hearing loss. Even in cases of profound hearing loss vestibular reactivity remained normal. Fourteen adult patients reported nondebilitating tinnitus. Overall, hearing impairment progressed with age. Patients with the T348M mutation were at highest risk of rapid progression of sensorineural hearing loss.

CONCLUSION

Patients with MWS are at risk of developing progressive sensorineural hearing loss without vestibular involvement. Hearing impairment starts at high frequencies and can subsequently progress to profound hearing loss. Progression is age dependent. Patients with different NLRP3 mutations had distinctly different trajectories of hearing loss, suggesting a mutation-specific risk that should be considered when making treatment decisions.

Effect of in vitro and in vivo anakinra on cytokines production in Schnitzler syndrome

IL-1 receptor antagonist anakinra is usually highly efficient in Schnitzler syndrome (SS), a rare inflammatory condition associating urticaria, fever, and IgM monoclonal gammopathy. In this study, we aimed to assess lipopolysaccharide (LPS)-induced production of inflammatory cytokines by peripheral blood mononuclear cells (PBMCs) before and after 1 month of anakinra in patients with SS. LPS-induced production of IL-1β, IL-6 and TNFα was assessed by enzyme-linked immunosorbent assay with and without anakinra in vitro, and before and after 1 month (in vivo condition) of treatment in 2 patients with SS. Spontaneous production of IL-1β, IL-6 and TNF-α by PBMCs was similar in the patients and the healthy controls and was almost undetectable. Stimulation with LPS caused a higher release of cytokines from the patients than from the healthy controls. Before in vivo anakinra start, in vitro adjunction of anakinra reduced the high LPS-induced production of IL-1β and TNFα in both patients and of IL-6 in one patient. After 1 month of treatment with anakinra, while the patients had dramatically improved, there was also a marked reduction in LPS-induced cytokines production, which was almost normalized in one patient. This study shows an abnormal LPS-induced inflammatory cytokines production in SS, which can be decreased or even normalized by in vitro and in vivo anakinra.

Efficacy and safety of anakinra therapy in pediatric and adult patients with the autoinflammatory Muckle-Wells syndrome

OBJECTIVE

Muckle-Wells syndrome (MWS) is an inherited autoinflammatory disease caused by mutations in the NLRP3 gene that result in excessive interleukin-1 (IL-1) release. It is characterized by severe fevers, rashes, arthralgia, and conjunctivitis, leading to sensorineural deafness and amyloidosis. The recombinant IL-1 receptor antagonist anakinra blocks the biologic activity of IL-1. The aim of this study was to determine the short- and long-term efficacy and safety of anakinra therapy in children and adults with severe MWS.

METHODS

A single-center observational study was performed. Standardized assessments included clinical features, the Disease Activity Score (DAS) for MWS, classic and novel markers of inflammation, and patient-derived measures of health status. The primary outcome was a score of <10 on the DAS for MWS at 2 weeks and at the last followup visit. Measures of MWS disease activity were investigated using descriptive statistics and paired comparative analysis.

RESULTS

A total of 12 patients with severe MWS (5 children and 7 adults) received anakinra for a median of 11 months (range 5-14 months). The median followup was 11 months (range 5-14 months). Disease activity was significantly lower in all patients at 2 weeks (P = 0.0005). Organ manifestations of MWS improved, as did all patient-derived measures of health status, markers of inflammation, and hearing loss in 2 of the patients. Levels of the novel neutrophil activation biomarker S100A12 followed clinical disease activity. Treatment was well tolerated, and no serious adverse events were observed.

CONCLUSION

Anakinra was found to be a safe and effective treatment of severe MWS, leading to a significant improvement in disease activity at 2 weeks as well as long-term. Anakinra therapy should therefore be considered in children and adults with severe MWS disease requiring IL-1 blockade.

Progressive familial hearing loss in Muckle-Wells syndrome

CONCLUSION

The age-dependent disease progression requires accelerating diagnosis of Muckle-Wells syndrome (MWS) in order to start treatment as early as possible. The most frequent, but not obligate symptoms are familial fatigue, hearing loss, and arthralgia. The design of further clinical trials should focus on hearing in order to document the long-term effect of anti-interleukin (IL)-1 drugs on hearing preservation.

OBJECTIVES

This paper describes the otologic features of a genetically defined syndrome causing progressive hearing loss by cochlear degeneration. This is the first study reporting the pretreatment otologic presentation of a selected population with familial MWS.

METHODS

A single-center cohort was examined by audiologic and neurotologic methods including pure tone audiograms, vestibular testing, and tinnitus questionnaire. The audiograms of members of the same family were compared to describe the family-specific risk of hearing loss progression.

RESULTS

Nineteen patients (aged 3-72 years) belonging to four families with three different mutations of the NLRP3 gene were examined. Almost all patients (89%, 17/19) demonstrated bilateral sensorineural hearing loss. Hearing loss started in the high frequencies and led to profound deafness in the most severe cases. Even in cases of profound hearing loss the vestibular caloric reactivity was normal. Nearly half of the adults reported intermittent or permanent tinnitus.

Neonatal autoimmune diseases: a critical review

Neonatal autoimmune diseases are distinctly rare. Most neonatal autoimmune diseases result from the transplacental transfer of maternal antibodies directed against fetal or neonatal antigens in various tissues. In neonatal lupus, the heart seems to be particularly susceptible. Primary autoimmunity in newborns, with the exception of familial autoinflammatory diseases, is virtually non-existent. The pathophysiologic basis for the development of neonatal autoimmunity is not entirely clear, but differences in the neonatal immune system compared with the adult immune system, as well as unique characteristics of target antigens in the newborn period may be important factors. Neonatal lupus is the most common presentation of autoimmunity in the newborn. But the characteristics defining neonatal lupus are not well defined and the presentation of neonatal lupus differs from that of classical lupus. Other neonatal autoimmune diseases involving the interaction between maternal antibodies and fetal/neonatal antigens include neonatal anti-phospholipid syndrome, Behcet's disease, neonatal autoimmune thyroid disease, neonatal polymyositis and dermatomyositis, neonatal scleroderma and neonatal type I diabetes mellitus. While autoantibodies have been detected in patients with neonatal autoimmune disease, the pathogenic role of autoantibodies has not been well defined. Other mechanisms may play a role in the development of neonatal autoimmunity, including fetal/maternal microchimerism and aberrant apoptosis of fetal cells. The autoinflammatory syndromes are a completely different category, but are also included in discussion of neonatal autoimmune diseases. The autoinflammatory syndromes include the cryopyrin associated periodic syndromes (CAPS) - familial cold autoinflammatory syndrome (FCAS), neonatal onset multisystem inflammatory disease (NOMID) and Muckle-Wells syndrome, which all share a common pathophysiologic mechanism.

Bridging the gap between the clinician and the patient with cryopyrin-associated periodic syndromes

Cryopyrin-associated periodic syndromes are categorized as a spectrum of three autoinflammatory diseases, namely familial cold auto-inflammatory syndrome, Muckle-Wells syndrome and chronic infantile neurological cutaneous articular syndrome. All are caused by mutations in the NLRP3 gene coding for cryopyrin and result in active interleukin-1 release: their rarity and shared clinical indicators involving skin, joints, central nervous system and eyes often mean that correct diagnosis is delayed. Onset occurs early in childhood, and life-long therapy with interleukin-1 blocking agents usually leads to tangible clinical remission and inflammatory marker normalization in a large number of patients, justifying the need to facilitate early diagnosis and thus avoid irreversible negative consequences for tissues and organs.

Evaluation of cochlear function using transient evoked otoacoustic emission in children with Familial Mediterranean Fever

OBJECTIVE

The aim of this study was to investigate cochlear functions in children with Familial Mediterranean Fever (FMF).

METHODS

Fifty-six FMF patients (112 ears) and 30 healthy control subjects (60 ears) were included in the study. Transient evoked otoacoustic emission (TEOAE) was investigated. Numerical measurements of TEOAE, except the correlation percentage (%), included response amplitude (dB) and signal/noise (SN) ratio.

RESULTS

There was no statistically significant difference in age and sex in the two groups. Mean TEOAE correlation percentage, signal/noise ratio, TEOAE amplitudes in 1, 1.5, 2, 3 and 4 Hz frequency values were not different between the two groups (p>0.05).

CONCLUSIONS

In this study using the TEOAE test, we found that FMF did not cause outer cell hair damage in children. In the literature, there is no study on outer cell hair damage in children or adults with FMF, so this is the first investigational study.

NLRP3 E311K mutation in a large family with Muckle-Wells syndrome--description of a heterogeneous phenotype and response to treatment

Introduction

Muckle-Wells syndrome (MWS) is an inherited autoinflammatory disease characterized by fever, rash, arthralgia, conjunctivitis, sensorineural deafness and potentially life-threatening amyloidosis. The NLRP3/CIAS1 E311K mutation caused a heterogeneous phenotype of MWS in a large family. This study analyzes the clinical spectrum, patterns of inflammatory parameters and reports on response to treatment.

Methods

A total of 42 patients and family members were screened for the presence of the NLRP3 mutation. Clinical symptoms were reviewed in all family members. Classical (erythrocyte sedimentation rate (ESR, C-reactive protein (CRP)) and novel MWS inflammatory markers (serum amyloid A (SAA), cytokines, cytokine receptor levels) were determined. Patients were treated with the IL-1 inhibitors Anakinra or Canakinumab.

Results

All 13 clinically affected patients were heterozygous carriers of the amino acid substitution p.Glu311Lys/E311K encoded by exon 3 of the NLRP3 gene, but none of the healthy family members. Disease manifestations varied widely. Except for one child, all carriers suffered from hearing loss and severe fatigue. TNF-α, IL-6, TNF-RI, and TNF-RII levels as well as SAA were elevated in three, two, one, six and ten patients, respectively. Both clinical and laboratory parameters responded quickly and sustainedly to treatment with Anakinra or Canakinumab.

Conclusion

The NLRP3 E311K mutation is associated with a heterogeneous clinical spectrum, which may expand the view on MWS presentation. The leading symptom was hearing loss. Pericarditis, a rare but severe clinical feature of MWS, was diagnosed in three patients. One patient had a severe course, which led to renal failure secondary to amyloidosis. IL-1 inhibition leads to rapid and sustained improvement of symptoms.

Cryopyrin-associated periodic syndromes: otolaryngologic and audiologic manifestations

OBJECTIVE

Cryopyrin-associated periodic syndromes (CAPS) represent a spectrum of CIAS1 gene-mediated autoinflammatory diseases characterized by recurrent systemic inflammation. The clinical spectrum of CAPS varies from mild to severe and includes the syndromes historically described as familial cold autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease (NOMID). This article presents the largest cohort of patients with CAPS. The objective is to describe the pathogenesis, otolaryngologic, and audiologic manifestations of CAPS.

STUDY DESIGN

Prospective (2003-2009).

SETTING

National Institutes of Health.

SUBJECTS AND METHODS

Fifty-seven patients with a diagnosis of CAPS were identified (31 NOMID, 11 NOMID/MWS, 9 MWS, and 6 FCAS). Comprehensive data regarding clinical manifestations, audiologic phenotype, and fluid attenuation inversion recovery MRI (FLAIR-MRI) of the brain and inner ear were obtained.

RESULTS

Complete audiologic data obtained on 70% of ears revealed conductive hearing loss in 4 (11%) NOMID ears and mixed hearing loss in 5 (13%) NOMID and 2 (14%) NOMID/MWS ears. Sensorineural hearing loss (SNHL), worse in higher frequencies, was the most common type of hearing loss and was present in 23 (61%) NOMID, 10 (71%) NOMID/MWS, and 4 (33%) MWS ears. All of the patients with FCAS had normal hearing except 2, who had SNHL from 4 to 8 kHz. On FLAIR-MRI sequence, cochlear enhancement was noted in 26 of 29 (90%) NOMID, 6 of 11 (55%) NOMID/MWS, 3 of 9 (33%) MWS, and 1 of 6 (17%) FCAS patients and was significantly associated with the presence of hearing loss. Maxillary sinus hypoplasia and mucosal thickening were found in 39% and 86% of the cohort, respectively.

CONCLUSION

CIAS1 pathway–mediated CAPS is associated with unregulated autoinflammation mediated by interleukin-1 in the cochlea and hearing loss. Timely diagnosis is crucial to initiate early treatment with interleukin-1 receptor antagonists.

NLRs in immune privileged sites

Innate immune receptors such as the nucleotide-binding domain, leucine-rich repeat-containing (NBD-LRR) receptors, referred to as NLRs, are known to serve as a critical component of host defense. However, their participation in inflammatory responses within immune privileged sites such as the brain and eye is less understood. The potential importance of NLRs in regulation of inflammation within these particular sites is further underscored by their association with autoinflammatory disorders, wherein localized inflammation can occur within the brain or eye as neuroinflammation or uveitis, respectively. Many NLRs are expressed within the brain and eye and in this review, we discuss their roles in the inflammation of the central nervous system (CNS) and uveitis.

Long term management of patients with cryopyrin-associated periodic syndromes (CAPS): focus on rilonacept (IL-1 Trap)

Cryopyrin-associated periodic syndromes (CAPS) are a group of inherited inflammatory disorders consisting of familial cold-induced autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease (NOMID; also known as chronic infantile neurologic, cutaneous, articular [CINCA] syndrome). These rare disorders are associated with heterozygous mutations in the NLRP3 (CIAS1) gene, which encodes the protein NALP3 or cryopyrin, and inflammation driven by excessive production of the cytokine interleukin-1β (IL-1β). Amyloidosis is a serious complication with 25% of MWS patients developing amyloidosis, with occasional fatal consequences, whilst up to 20% of CINCA/NOMID patients die from various complications, before reaching the early adulthood. In some CINCA/NOMID adult survivors amyloidosis can also occur. Prior to the discovery of the CIAS1 gene mutations and the advent of IL-1 targeted therapy, treatment was aimed at suppressing inflammation, with limited success. The selective blockade of IL-1β, with anakinra (IL-1 receptor antagonist), not only provided supportive evidence for the role of IL-1β in CAPS, but also demonstrated the efficacy of targeting IL-1β for treatment of these conditions. In February, 2008, ‘Orphan Drug’ approval from the Food and Drug Administration (FDA) for rilonacept (IL-1 Trap/Arcalyst^™, Regeneron Pharmaceuticals, Inc) was given for the treatment of two CAPS disorders, FCAS and MWS in adults and children 12 years and older, making rilonacept the first therapy approved for the treatment of CAPS.

Canakinumab: a human anti-IL-1β monoclonal antibody for the treatment of cryopyrin-associated periodic syndromes

The cryopyrin-associated periodic syndromes (CAPS) are a group of rare inherited inflammatory diseases associated with overproduction of IL-1β. Canakinumab, developed by Novartis AG (Basel, Switzerland), is an intravenously or subcutaneously administered, fully human monoclonal antibody that neutralizes the bioactivity of human IL-1β. Canakinumab has promising clinical safety and pharmacokinetic properties, and has demonstrated potential for the treatment of CAPS. Canakinumab was recently granted EU orphan drug status for systemic-onset juvenile idiopathic arthritis, and early clinical trials have established that administration of canakinumab every 2 weeks is both safe and effective. Subcutaneous canakinumab (approved formulation) offers some advantages over the existing IL-1β-blocking treatment, anakinra, which must be injected daily and is often not well tolerated by patients. The long-term safety of all targeted anti-IL-1 therapies in CAPS remains an unanswered question owing to the relatively short clinical experience with these agents; as canakinumab produces sustained IL-1 suppression, vigilance is necessary to diagnose the development of adverse events, especially any associated infections.

Cryopyrin-associated periodic syndrome: an update on diagnosis and treatment response

Cryopyrin-associated periodic syndrome (CAPS) is a rare hereditary inflammatory disorder encompassing a continuum of three phenotypes: familial cold autoinflammatory syndrome, Muckle-Wells syndrome, and neonatal-onset multisystem inflammatory disease. Distinguishing features include cutaneous, neurological, ophthalmologic, and rheumatologic manifestations. CAPS results from a gain-of-function mutation of the NLRP3 gene coding for cryopyrin, which forms intracellular protein complexes known as inflammasomes. Defects of the inflammasomes lead to overproduction of interleukin-1, resulting in inflammatory symptoms seen in CAPS. Diagnosis is often delayed and requires a thorough review of clinical symptoms. Remarkable advances in our understanding of the genetics and the molecular pathway that is responsible for the clinical phenotype of CAPS has led to the development of effective treatments. It also has become clear that the NLRP3 inflammasome plays a critical role in innate immune defense and therefore has wider implications for other inflammatory disease states.

Risk factors for severe Muckle-Wells syndrome

OBJECTIVE

Muckle-Wells syndrome (MWS) is an inherited autoinflammatory disease resulting in excessive interleukin-1 release. It is unknown whether demographic, clinical, or laboratory characteristics at the time of diagnosis may identify patients who are at high risk for severe disease activity. This study was undertaken to analyze clinical and laboratory features of MWS, compare genetically defined subcohorts, and identify risk factors for severe MWS.

METHODS

A multicenter cohort study of consecutive MWS patients was performed. Parameters assessed included clinical features, MWS Disease Activity Score (MWS-DAS), inflammation markers, and cytokine levels. E311K mutation-positive patients were compared with E311K mutation-negative patients. Putative risk factors for severe MWS (defined as an MWS-DAS score of ≥10) were assessed in univariate analyses, and significant predictors were entered into a multivariate model.

RESULTS

Thirty-two patients (15 male and 17 female) were studied. The most frequent organ manifestations were musculoskeletal symptoms and eye and skin disorders. Renal disease and hearing loss were seen in >50% of the patients. Genetically defined subcohorts had distinct phenotypes. Severe disease activity was documented in 19 patients (59%). Predictors of severe MWS identified at the time of diagnosis were female sex, hearing loss, musculoskeletal disease, increased erythrocyte sedimentation rate, and low hemoglobin level. Female sex and hearing loss remained significant after adjustment for age in a multivariate model (relative risk 1.8 and 2.6, respectively).

CONCLUSION

MWS patients at high risk for severe disease can be identified at the time of diagnosis. Female patients presenting with hearing loss have the highest likelihood of manifesting severe MWS and should be considered a high-risk group.

Interleukin-1β inhibitors for the treatment of cryopyrin-associated periodic syndrome

Cryopyrin-associated periodic syndrome (CAPS) comprises a group of rare, but severe, inherited autoinflammatory disorders associated with aberrant secretion of interleukin (IL)-1. These distinct conditions of autoinflammatory origin include Muckle–Wells syndrome, familial cold autoinflammatory syndrome, and neonatal-onset multisystem inflammatory disease (NOMID), which is also referred to as chronic infantile neurologic cutaneous and articular syndrome. Recently, this group of diseases has been associated with mutations in the NLRP3 gene that encodes for the protein cryopyrin, a component of the inflammasome complex that regulates the maturation and secretion of inflammatory cytokine IL-1β. Immune cells from patients with NOMID secrete higher levels of active IL-1β compared with monocytes from healthy subjects. Overproduction of IL-1 is believed to promote aberrant inflammatory response in CAPS patients. Evidence supporting the clinical value of IL-1β in CAPS has been provided from the complete response of patients after treatment with IL-1 blocking agents.

Periodic Fever syndromes

The periodic syndromes represent a heterogeneous group of disorders that can be very difficult for practicing physicians to diagnosis and treat. This article presents an orderly approach to hyperimmunoglobulin D syndrome; tumor necrosis factor receptor-1 periodic syndrome; familial Mediterranean fever; periodic fever with aphthous stomatitis, pharyngitis, and adenitis syndrome; and cryopyrin-associated periodic syndromes by highlighting the disease presentation, diagnosis, pathogenesis, and treatment. Recent advances are also discussed.

IL-1β is overexpressed and aberrantly regulated in corticosteroid nonresponders with autoimmune inner ear disease

Autoimmune inner ear disease is an enigmatic disorder characterized by recurring episodes of sudden or progressive sensorineural hearing loss. Hearing loss can be improved by timely corticosteroid administration, but only half of those treated respond, and for many responders, that response is lost over time. The mechanisms that control corticosteroid responsiveness in this disorder are largely uncharacterized. We have previously identified that the induction by dexamethasone of IL-1R type II (IL-1R2) expression in PBMC predicts corticosteroid responsiveness in this disorder. In this study, we asked whether IL-1β was overexpressed, and whether clinical corticosteroid responders differentially regulated IL-1β expression or release in response to dexamethasone, as compared with nonresponders. IL-1β has been reported to induce matrix metalloproteinase-9 (MMP-9) expression. Given that metalloproteinases can cleave IL-1R2, we also asked whether MMP-9 expression was altered in this disorder. In this study, we demonstrate that corticosteroid nonresponders have elevated plasma levels of IL-1β and MMP-9 as compared with clinically responsive patients (p = 0.0008 and p = 0.037, respectively). Increasing MMP-9 expression correlated with increasing IL-1β concentration, suggesting that IL-1β expression regulates MMP-9 expression. As expected, monocytes were the predominant producers of IL-1β. In vitro exposure of PBMC to dexamethasone from clinical corticosteroid responders suppressed IL-1β release. PBMC of corticosteroid nonresponders have substantially higher release of IL-1β into the conditioned media, and when exposed to dexamethasone, failed to repress IL-1β release (p = 0.05). Treatment of PBMC from clinical corticosteroid nonresponders with anakinra resulted in repression of IL-1β release, suggesting that IL-1β blockade may be a viable therapy for these patients.

Intra-articular Anakinra for the Treatment of Persistent Inflammation and Arthrofibrosis following Anterior Cruciate Ligament Reconstruction

Purpose

Postoperative inflammation and arthrofibrosis remain difficult problems following ACL reconstruction. Interleukin-1 (IL-1) is a potent driver of intra-articular inflammation and arthrofibrosis following injury and surgery. Anakinra (Kineret, Amgen, Thousand Oaks, CA) is an IL-1 receptor antagonist. We hypothesize that postoperative intra-articular anakinra use decreases inflammation and subsequent arthrofibrosis, reducing the need for arthroscopic debridement and manipulation under anesthesia.

Methods

Four patients (ages 15-56) who were treated with anakinra for persistent postoperative inflammation and scarring within 4 months of ACL reconstruction were retrospectively reviewed. Anakinra was utilized when patients were unable to obtain full extension and at least 90° of flexion 1 month postoperatively in association with persistent effusions or decreased patellar mobility.

Results

Anakinra injection was performed between 36 and 97 days postsurgery. All four reported improvements in range of motion and decreased pain and effusions within 10 days of injection. One patient, who did not receive anakinra until more than 3 months postsurgery, required eventual arthroscopic debridement of a cyclops lesion but none of the patients required frank lysis of adhesions or manipulation under anesthesia. No adverse reactions to anakinra occurred.

Conclusion

Based on previous experience, we believe that all of these patients would have required arthroscopic debridement of scar tissue and manipulation under anesthesia to regain motion were not for the anakinra treatment. Clearly, the concept of IL-1 inhibition in the postoperative knee requires further research, but early results are promising for this unique treatment of a difficult clinical problem.

[CAPS treatment]

Non-steroidal anti-inflammatories, corticoids and antihistamines, as well as a great many other molecules, have classically been used to control the symptoms of cryopyrin-associated periodic syndromes (CAPS), with very few encouraging results. Knowledge of its genetic character, and its aetiopathogenesis associated with inflammasome and the production of interleukin-1 (IL-1) has led to the development of new therapeutic weapons that have not just obtained improvements of the symptoms and quality of life of the patients, but also managed to control the underlying inflammation. Results show that anakinra, an IL-1 receptor antagonist molecule, improved the clinical symptoms and the inflammatory markers of patients with CAPS has motivated research with other molecules directed against IL-1: rilonacept and canakinumab. It is likely that the use of these molecules could prevent the development of the late complications associated with chronic inflammation.

[Cutaneous amyloidosis]

Amyloids are common protein aggregates in nature. Some amyloids fulfill important biological tasks while others are known to cause diseases. Despite the fact that the ultrastructure of amyloid is highly conserved, the mechanism of amyloidogenesis remains a challenging research topic. In humans, amyloidoses may develop in the skin or lead to skin signs due to secondary cutaneous involvement. An accurate diagnostic procedure is crucial for planning the therapy of this heterogeneous group of diseases. Therefore, the aim of this paper is to give an overview on the different kinds of amyloidoses as well as on diagnostic and therapeutic approaches. Furthermore, the discrimination between functional and disease-causing amyloid is briefly presented.

An inflammasome-independent role for epithelial-expressed Nlrp3 in renal ischemia-reperfusion injury

Cytoplasmic innate immune receptors are important therapeutic targets for diseases associated with overproduction of proinflammatory cytokines. One cytoplasmic receptor complex, the Nlrp3 inflammasome, responds to an extensive array of molecules associated with cellular stress. Under normal conditions, Nlrp3 is autorepressed, but in the presence of its ligands, it oligomerizes, recruits apoptosis-associated speck-like protein containing a caspase recruitment domain (Asc), and triggers caspase 1 activation and the maturation of proinflammatory cytokines such as IL-1β and IL-18. Because ischemic tissue injury provides a potential source for Nlrp3 ligands, our study compared and contrasted the effects of renal ischemia in wild-type mice and mice deficient in components of the Nlrp3 inflammasome (Nlrp3(-/-) and Asc(-/-) mice). To examine the role of the inflammasome in renal ischemia-reperfusion injury (IRI) we also tested its downstream targets caspase 1, IL-1β, and IL-18. Both Nlrp3 and Asc were highly expressed in renal tubular epithelium of humans and mice, and the absence of Nlrp3, but not Asc or the downstream inflammasome targets, dramatically protected from kidney IRI. We conclude that Nlrp3 contributes to renal IRI by a direct effect on renal tubular epithelium and that this effect is independent of inflammasome-induced proinflammatory cytokine production.

Critical appraisal of canakinumab in the treatment of adults and children with cryopyrin-associated periodic syndrome (CAPS)

The cryopyrin-associated syndromes (CAPS) include three autosomal-dominant syndromes, that are caused by a mutation in the NLRP3 gene on chromosome 1, encoding the cryopyrin protein. These syndromes, familial cold autoinflammatory syndrome, Muckle-Wells syndrome and neonatal-onset multisystem inflammatory disease, are characterized by urticaria-like rash, fever, central nervous system inflammation, an arthropathy and a risk of the development of amyloidosis in a respectively escalating degree of severity between the various syndromes. Recently the role of cryopyrin in the regulation of interleukin (IL)-1 production and activation was described and anti IL-1 therapies were found to be very effective in treating these syndromes. There are several types of anti IL-1 medications based on different mechanisms of antagonizing IL-1. This paper focuses on the efficacy and safety of canakinumab, a long-acting humanized anti IL-1 antibody, in treating these syndromes.

Otolaryngological manifestations of 'Muckle-Wells syndrome'

We present a follow-up of a cohort of three cases of Muckle-Wells syndrome (MWS). The aim of this report is to characterise the symptoms of this rare autosomal dominant condition with respect to the ENT practice. A retrospective analysis of the clinical features of MWS from our outpatient follow-up record of the three patients diagnosed with MWS. An extensive literature search was performed, using Medline through Pub Med (1950-2010), EMBASE (1980-2009) and Ovid (1958-2009). Retrospective case note study. In the present cohort, progressive sensorineural hearing loss was the main presentation and has been followed up over 10 years (median). The spectrum of head and neck presentation from the world literature was reviewed and includes hypothyroidism, amyloid goitre, cervical lymphadenopathy, and facial rash. This is the first documented report of the Otolaryngological features of the MWS in the English ENT literature. An awareness of this rare syndrome is essential in order to diagnose this uncommon syndrome and thus to plan for a long-term follow-up.

Cryopyrin-associated periodic syndromes: background and therapeutics

Cryopyrin-associated periodic syndromes (CAPS) are caused by mutations of the gene encoding the NLR family protein NLRP3, which together with caspase-1 and adaptor proteins constitutes a protein complex termed the inflammasome. In innate immune reactions, a variety of stimuli activate the NLRP3 inflammasome, triggering caspase-1 to process proIL-1 and thus to produce mature IL-1. Excessive production of IL-1 by monocytes/macrophages is the central pathophysiology of CAPS, and daily injection of the IL-1 receptor antagonist anakinra rapidly ameliorates the inflammatory symptoms in most cases. Furthermore, double-blind, placebo-controlled clinical trials have recently confirmed the efficacy and safety of rilonacept, a fusion protein of the IL-1 receptor and IgG Fc, and canakinumab, a human anti-IL-1 monoclonal antibody, as novel long-lasting agents for treating CAPS.

Unleashing the therapeutic potential of NOD-like receptors

Nucleotide-binding and oligomerization domain (NOD)-like receptors (NLRs) are a family of intracellular sensors that have key roles in innate immunity and inflammation. Whereas some NLRs - including NOD1, NOD2, NAIP (NLR family, apoptosis inhibitory protein) and NLRC4 - detect conserved bacterial molecular signatures within the host cytosol, other members of this family sense 'danger signals', that is, xenocompounds or molecules that when recognized alert the immune system of hazardous environments, perhaps independently of a microbial trigger. In the past few years, remarkable progress has been made towards deciphering the role and the biology of NLRs, which has shown that these innate immune sensors have pivotal roles in providing immunity to infection, adjuvanticity and inflammation. Furthermore, several inflammatory disorders have been associated with mutations in human NLRgenes. Here, we discuss the effect that research on NLRs will have on vaccination, treatment of chronic inflammatory disorders and acute bacterial infections.