Developments in the scientific and clinical understanding of autoinflammatory disorders

Familial Mediterranean Fever Gene Mutations and Gout as an Auto-Inflammatory Arthropathy

Introduction:

The auto-inflammatory diseases (AID) are a heterogeneous group of multi-system disorders of innate immunity dysregulation. MEFV gene has major role in AID.

Aim:

The aim of this study is to investigate the frequency of MEFV variant alleles in gout patients as an AID and their genotype-phenotype relationship.

Methods:

Total amount of 224 of the healthy people as a control group (113 male and 111 female) and 24 gouty arthritis patients (20 male and 4 female) entered this study. Blood samples screened for the 12 common pathogenic mutations according to manufacturer’s instructions.

Results:

The mean age of patients was 54 years. MTP joint was the most involved joint (91.66%). Mutations were shown in 5 patients (20.83%) that were not different from healthy population (25%). Five patients carry one mutated MEFV allele, E148Q in 4 patients and V726A in 1 patient. Control group showed 25% mutations as E148Q (18.3%), P369S (3.1%), V726A (2.2%), A744S (1.3%) respectively. The most common mutation detected in patients was E148Q (16.66%) and all of them were males. No significant and meaningful associations were detected between the MEFV gene mutations and gouty arthritis patients.

Conclusion:

There was not any correlation between MEFV gene mutations carriage with age, sex, the number of joint involvement and the course of disease in gouty arthritis. MEFV gene mutations were more frequent in men than women, but this is not statistically significant.

Recognising and understanding cryopyrin-associated periodic syndrome in adults

Cryopyrin-associated periodic syndrome (CAPS) is a group of rare hereditary autoinflammatory diseases characterised by recurrent flares of mild to severe systemic inflammation and fever. CAPS is the umbrella term for a spectrum of individual conditions, namely familial cold autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS) and neonatal-onset multisystem inflammatory disease (NOMID), also known as chronic infantile neurologic, cutaneous and articular (CINCA) syndrome. The flare symptoms include fever, fatigue, rashes, headaches, arthralgia and myalgia that can last for a few hours or for several days. These symptoms are debilitating, contributing to poor quality of life for patients if left untreated. Serious life-changing complications such as hearing loss, blindness and AA amyloidosis resulting in kidney failure can occur. Until recently, treatment of the disease was symptomatic using non-steroidal anti-inflammatory and immunosuppressant drugs with limited success. In contrast, biological treatments targeting interleukin 1 (IL-1) have proved remarkably effective, often associated with complete and sustained disease remission, vastly improved quality of life and avoidance of serious long-term complications.

Reducing the Toxicity Risk in Antibiotic Prescriptions by Combining Ontologies with a Multiple Criteria Decision Model

We consider the risk of adverse drug events caused by antibiotic prescriptions. Antibiotics are the second most common cause of drug related adverse events and one of the most common classes of drugs associated with medical malpractice claims. To cope with this serious issue, physicians rely on guidelines, especially in the context of hospital prescriptions. Unfortunately such guidelines do not offer sufficient support to solve the problem of adverse events. To cope with these issues our work proposes a clinical decision support system based on expert medical knowledge, which combines semantic technologies with multiple criteria decision models. Our model links and assesses the adequacy of each treatment through the toxicity risk of side effects, in order to provide and explain to physicians a sorted list of possible antibiotics. We illustrate our approach through carefully selected case studies in collaboration with the EpiCURA Hospital Center in Belgium.

Kidney involvement in the Schnitzler syndrome, a rare disease

The Schnitzler syndrome (SS) is a rare and underdiagnosed entity that associates a chronic urticarial rash, monoclonal IgM (or sometimes IgG) gammopathy and signs and symptoms of systemic inflammation. During the past 45 years, the SS has evolved from an elusive little-known disorder to the paradigm of a late-onset acquired auto-inflammatory syndrome. Though there is no definite proof of its precise pathogenesis, it should be considered as an acquired disease involving abnormal stimulation of the innate immune system, which can be reversed by the interleukin-1 receptor antagonist anakinra. It clearly expands our view of this group of rare genetic diseases and makes the concept of auto-inflammation relevant in polygenic acquired diseases as well. Increasing numbers of dermatologists, rheumatologists, allergologists, haematologists and, more recently, nephrologists, recognize the SS. The aim of this review is to focus on kidney involvement in the SS. Although the literature regarding kidney involvement in the SS is very poor it can be severe, as in our own case here reported, leading us to recommend the systematic search for nephropathy markers in the SS.

Cytokine signatures in hereditary fever syndromes (HFS)

Hereditary fever syndromes (HFS) include a group of disorders characterized by recurrent self-limited episodes of fever accompanied by inflammatory manifestations occurring in the absence of infection or autoimmune reaction. Advances in the genetics of HFS have led to the identification of new gene families and pathways involved in the regulation of inflammation and innate immunity. The key role of several cytokine networks in the pathogenesis of HFS has been underlined by several groups, and supported by the rapid response of patients to targeted cytokine blocking therapies. This can be due to the direct effect of cytokine overproduction or to an absence of receptor antagonist resulting in dysbalance of downstream pro- and anti-inflammatory cytokine networks. The aim of this study was to present an overview and to discuss the major concepts regarding the cellular and molecular immunology of HFS, with a particular focus on their specific cytokine signatures and physiopathological implications. Based on their molecular and cellular mechanisms, HFS have been classified into intrinsic and extrinsic IL-1β activation disorders or inflammasomopathies, and protein misfolding disorders. This review integrates all recent data in an updated classification of HFS.

Role of biologics in intractable urticaria

Chronic urticaria (CU) is a common condition faced by many clinicians. CU has been estimated to affect approximately 0.5%-1% of the population, with nearly 20% of sufferers remaining symptomatic 20 years after onset. Antihistamines are the first-line therapy for CU. Unfortunately, nearly half of these patients will fail this first-line therapy and require other medication, including immune response modifiers or biologics. Recent advances in our understanding of urticarial disorders have led to more targeted therapeutic options for CU and other urticarial diseases. The specific biologic agents most investigated for antihistamine-refractory CU are omalizumab, rituximab, and intravenous immunoglobulin (IVIG). Of these, the anti-IgE monoclonal antibody omalizumab is the best studied, and has recently been approved for the management of CU. Other agents, such as interleukin-1 inhibitors, have proved beneficial for Schnitzler syndrome and cryopyrin-associated periodic syndromes (CAPS), diseases associated with urticaria. This review summarizes the relevant data regarding the efficacy of biologics in antihistamine-refractory CU.

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.

Monogenic autoinflammatory diseases

During the past 15 years, a growing number of monogenic inflammatory diseases have been described and their respective responsible genes identified. The proteins encoded by these genes are involved in the regulatory pathways of inflammation and are mostly expressed in cells of the innate immune system. Diagnosis remains clinical, with genetic confirmation where feasible. Although a group of patients exhibit episodic systemic inflammation (periodic fevers), these disorders are mediated by continuous overproduction and release of pro-inflammatory mediators, such as IL-1 and IL-6, and TNF and are best considered as autoinflammatory diseases rather than periodic fevers. Treatment with biologic agents that block these cytokines, particularly IL-1, has proved to be dramatically effective in some patients. Still, in many cases of autoinflammation no genetic abnormalities are detected and treatment remains suboptimal, raising the question of novel pathogenic mutations in unexplored genes and pathways.

Ultrasonographic assessment reveals detailed distribution of synovial inflammation in Blau syndrome

INTRODUCTION

Arthritis is the most frequent manifestation of Blau syndrome, an autoinflammatory disorder caused by the genetic mutation of NOD2. However, detailed information on arthritis in Blau syndrome on which the therapeutic strategy should be based on is lacking. This multi-center study aimed to accurately characterize the articular manifestation of Blau syndrome and also to demonstrate the utility of musculoskeletal ultrasound in Blau syndrome.

METHODS

Patients who had been diagnosed with Blau syndrome by genetic analysis of NOD2 were recruited. A total of 102 synovial sites in 40 joints were assessed semiquantitatively by ultrasound for gray-scale synovitis and synovial power Doppler (PD) signal.

RESULTS

In total, 10 patients whose age ranged from 10 months to 37 years enrolled in this study. Although only 4 joints (0.8%) were tender on physical examination, 81 joints (16.9%) were clinically swollen. Moreover, 240 (50.0%), and 124 (25.8%) joints showed gray-scale (GS) synovitis and synovial PD signal on ultrasound, respectively. Importantly, GS synovitis was present in 168 out of 399 non-swollen joints, in which 61 also exhibited synovial PD signal. Among 40 joint regions, the ankle, the wrist, and the proximal interphalangeal joints were the most frequently and severely affected joints. Comparisons between different synovial tissues demonstrated a significantly higher proportion of the joints with tenosynovitis as compared with that with intra-articular synovitis (41.5% versus 27.9%, P < 0.0001). In respect of age and treatment, synovial PD signals were minimal in the youngest patient and in the oldest two patients, and were relatively mild in patients receiving treatment with methotrexate plus TNF antagonists. In two patients who underwent the second ultrasound examination, total PD scores markedly decreased after initiating the treatment with a tumor necrosis factor (TNF) antagonist.

CONCLUSIONS

The detailed information on synovial inflammation obtained by ultrasound confirms the dissociation between pain and inflammation and the frequently involved joint regions and synovial tissue in the arthritis of Blau syndrome. Our data also demonstrate that ultrasonography can be a potent tool in monitoring the activity of synovial inflammation and in investigating the pathophysiology of arthritis in this rare but archetypical autoinflammatory condition.

The association of TNFRSF1A gene and MEFV gene mutations with adult onset Still's disease

Adult onset Still's disease (ASD) is a systemic inflammatory disorder of unknown etiology. ASD is characterized by fever with unknown etiology, rash, arthritis, and involvement of several organ systems. FMF and TRAPS are two important autoinflammatory diseases which characterized with recurrent inflammatory attacks. We aimed in this study to investigate the MEFV gene and TNFRSF1A gene variations in ASD. Twenty consecutive Turkish ASD patients (14 female and 6 male; mean age 38.45 ± 14; mean disease duration 3.3 ± 2.3; mean age of the disease onset 35.1 ± 14.4) and 103 healthy controls of Turkish origin were analyzed. All ASD patients were genotyped for the 4 MEFV mutations (M694V, E148Q, V726A, M680I) and TNFRSF1A gene exon 2-3 and exon 4-5 by using sequence analysis. The healthy controls are genotyped using PCR-RFLP method for intron 4 variation. The results of MEFV gene mutations screening show an increase in the MEFV mutation rate in ASD group, but it was not significantly different (p = 0.442, OR 1.64, 95 % CI 0.409-6.589). T-C polymorphism (rs1800692) was the only variation in the intron 4 of TNFRSF1A gene that we observed at the ASD patients. The frequency of TT genotype was 15 %, TC: 45 %, and CC: 40 % in ASD patients and the frequencies were 22, 41, and 37 % in healthy controls, respectively. When we analyzed the allele difference between both groups, there was no difference (p = 0.54, OR 1.24, 0.619-2.496-2.654). The variations in MEFV may have role in ASD pathogenesis. Our findings suggest that there is no significant association between ASD and TNFRSF1A variations.

Febrile conditions in rheumatology

Fever is not the most frequent symptom in rheumatology; however, its occurrence always draws attention to a severe underlying pathologic process. The rheumatologic assessment of febrile patients usually takes place for three reasons: the patient's fever is associated with known rheumatic disease or musculoskeletal symptoms, or rheumatologic cause is suggested as the underlying cause of fever of unknown origin. The primary task of the rheumatologist is to rule out infections and autoimmune processes. In addition to the musculoskeletal and accompanying symptoms, the information about the course of fever and the observation of the continuity or periodicity of fever provide help to establish the diagnosis. A summarising discourse about this issue is rarely published in this speciality; therefore, we found it important to provide an overview of rheumatological diseases accompanied by fever.

Spontaneous inflammatory pain model from a mouse line with N-ethyl-N-nitrosourea mutagenesis

BACKGROUND

N-ethyl-N-nitrosourea mutagenesis was used to induce a point mutation in C57BL/6 J mice. Pain-related phenotype screening was performed in 915 G3 mice. We report the detection of a heritable recessive mutant in meiotic recombinant N1F1 mice that caused an abnormal pain sensitivity phenotype with spontaneous skin inflammation in the paws and ears.

METHODS

We investigated abnormal sensory processing, neuronal peptides, and behavioral responses after the induction of autoinflammatory disease. Single-nucleotide polymorphism (SNP) markers and polymerase chain reaction product sequencing were used to identify the mutation site.

RESULTS

All affected mice developed paw inflammation at 4-8 weeks. Histological examinations revealed hyperplasia of the epidermis in the inflamed paws and increased macrophage expression in the spleen and paw tissues. Mechanical and thermal nociceptive response thresholds were reduced in the affected mice. Locomotor activity was decreased in affected mice with inflamed hindpaws, and this reduction was attributable to the avoidance of contact of the affected paw with the floor. Motor strength and daily activity in the home cage in the affected mice did not show any significant changes. Although Fos immunoreactivity was normal in the dorsal horn of affected mice, calcitonin gene-related peptide immunoreactivity significantly increased in the deep layer of the dorsal horn. The number of microglia increased in the spinal cord, hippocampus, and cerebral cortex in affected mice, and the proliferation of microglia was maintained for a couple of months. Two hundred eighty-five SNP markers were used to reveal the affected gene locus, which was found on the distal part of chromosome 18. A point mutation was detected at A to G in exon 8 of the pstpip2 gene, resulting in a conserved tyrosine residue at amino acid 180 replaced by cysteine (Y180 C).

CONCLUSIONS

The data provide definitive evidence that a mutation in pstpip2 causes autoinflammatory disease in an N-ethyl-N-nitrosourea mutagenesis mouse model. Thus, our pstpip2 mutant mice provide a new model for investigating the potential mechanisms of inflammatory pain.

Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome: a case report

Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature syndrome is a recently described chronic inflammatory syndrome consisting of widespread annular violaceous skin lesions and multisystemic inflammatory manifestations. We report a 12½-year-old boy with a young-age onset of recurrent fevers, annular violaceous plaques, alopecia areata, lipodystrophy, low weight and height, deformed fingers, wide-spaced nipples, chronic anemia, and elevated acute phase reactants. An abdominal punch biopsy demonstrated dense perivascular and interstitial infiltrates in the dermis, composed mainly of mononuclear cells. This syndrome may represent a new autosomal recessive auto-inflammatory genodermatosis. Increased awareness may lead to the discovery of more cases, and clarify its pathogenesis.

Canakinumab for treatment of cryopyrin-associated periodic syndrome

IMPORTANCE OF THE FIELD

Autoinflammatory syndromes such as cryopyrin-associated periodic syndromes (CAPS) place a heavy burden on affected individuals as well as on their families due to significant morbidity and increased mortality. The inflammatory response in CAPS is caused by an overwhelming activation of the pro-inflammatory cytokine IL-1, which was identified as a promising treatment target.

AREAS COVERED IN THIS REVIEW

This article focuses on the pathogenic background and different clinical manifestations in CAPS. Furthermore, the development program and characteristics of canakinumab, a recently approved fully human anti-IL-1β mAb for the treatment of CAPS, are described and compared to other available IL-1 blocking agents.

WHAT THE READER WILL GAIN

Canakinumab targets selectively human IL-1ß with high affinity and prevents the cytokine from interaction to its receptor and, thus, effectively blocks the inflammatory response in CAPS. In all studies performed, canakinumab showed a rapid improvement of symptoms of CAPS and a complete clinical response was achieved in most patients. Inflammatory markers such as C-reactive protein and serum amyloid-A protein were reduced to normal levels within few days. In comparison to other IL-1 blockers, canakinumab provides a longer plasma half-life and less injection site reactions.

TAKE HOME MESSAGE

Canakinumab offers the possibility of permanent disease control, almost symptom-free life, and hopefully less long-term morbidity and mortality in patients with CAPS.

[Consensus Document on the differential diagnosis and therapeutic approach to recurrent fever by the Paediatric Infectology Society and the Paediatric Rheumatology Society]

Recurrent fever is a relatively common problem during childhood. Diagnosis is often easy and related to mild viral infections. However a small proportion of these cases originate from an underlying non-infectious process that is generally difficult to diagnose. In this paper we describe the differential diagnosis of recurrent or periodic fever versus other processes, with especial attention to autoinflammatory disorders (AD). AD are alterations of innate immunity, and they have been recently classified as an immunodeficiency. Anyhow, since infections are not present, these processes are different to the classic primary immunodeficiency. An important part of AD is of known genetic aetiology. The symptoms originate from an underlying inflammatory process and can have different clinical expressions. One of the most relevant groups is the hereditary syndromes of periodic fever. This group of diseases associates recurrent fever and several clinical symptoms with a relative periodicity, separated by intervals free or almost free of symptoms. We include the diagnostic criteria for some processes as well as the characteristics that should, eventually, lead to a genetic study. Although treatment should be individualised, we also include some general recommendations.

The Schnitzler syndrome

The Schnitzler syndrome is a rare and underdiagnosed entity which is considered today as being a paradigm of an acquired/late onset auto-inflammatory disease. It associates a chronic urticarial skin rash, corresponding from the clinico-pathological viewpoint to a neutrophilic urticarial dermatosis, a monoclonal IgM component and at least 2 of the following signs: fever, joint and/or bone pain, enlarged lymph nodes, spleen and/or liver, increased ESR, increased neutrophil count, abnormal bone imaging findings. It is a chronic disease with only one known case of spontaneous remission. Except of the severe alteration of quality of life related mainly to the rash, fever and pain, complications include severe inflammatory anemia and AA amyloidosis. About 20% of patients will develop a lymphoproliferative disorder, mainly Waldenström disease and lymphoma, a percentage close to other patients with IgM MGUS. It was exceedingly difficult to treat patients with this syndrome until the IL-1 receptor antagonist anakinra became available. Anakinra allows a complete control of all signs within hours after the first injection, but patients need continuous treatment with daily injections.

In many aspects, the Schnitzler syndrome resembles the genetically determined auto-inflammatory syndromes involving activating mutations of the NLRP3 inflammasome. This latter point and its consequences will be addressed.

A novel TNFRSF1 gene mutation in a Turkish family: a report of three cases

Tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is an autosomal dominantly inherited rare autoinflammatory disease. It is caused by mutations in exons 2-3 and 4-5 of the tumor necrosing factor receptor superfamily 1A (TNFRSF1A) gene on chromosome 12p13.2. TNFRSF1A gene encodes the 55-kDa receptor for tumor necrosis factor. Attacks are associated with abdominal pain, myalgia, erythematous skin rash, conjunctivitis, and periorbital edema. Until now, more than 80 mutations have been identified. We herein report three patients with TRAPS of Turkish origin. The patients were followed up in our outpatient clinic in Kocaeli University Division of Rheumatology. Because of their TRAPS associated clinical features, we isolated genomic DNA from whole blood and sequenced the exon 2-3 and 4-5 third exon of TNFRSF1A gene after amplification with appropriate primers. One of the patients with TRAPS was 47-year-old female, who described recurrent attacks of fever, urticarial rash, conjunctivitis, arthralgia, myalgia, abdominal pain, thoracic pain, headache, fatigue, and elevated acute phase response since her childhood. With the sequencing of the TNFRSF1A gene, we identified heterozygous C29R mutation, which has not been reported before in any TRAPS patient. The other patients are her sons with similar findings and age 29 and 26. They were heterozygous for C29R mutation in TNFRSF1A gene too. We report novel C29R mutation in three TRAPS patients of Turkish origin, in which the main clinical features are recurrent fever attacks, erythematous skin rash, conjunctivitis, myalgia, and arthralgia. Treatment with steroids resolved the symptoms and lesions.

[Autoinflammatory diseases in childhood]

Autoinflammatory diseases are a group of monogenic inflammatory diseases with an early onset in childhood. Previously these diseases were summarized as"periodic fever syndromes." Included in this spectrum are familial Mediterranean fever, mevalonate kinase deficiency, and tumor necrosis factor receptor-associated disease. They are characterized by periodic or recurrent episodes of systemic inflammation causing fever, accompanied by rash, serositis, lymphadenopathy, arthritis, and other clinical manifestations. The other large group of autoinflammatory diseases consists of the cryopyrin-associated periodic syndromes, which include the cryopyrinopathies. The mildest form is familial cold-associated syndrome, a more severe form is Muckle-Wells syndrome, and the most severe is neonatal-onset multisystem inflammatory disease/chronic infantile neurological cutaneous and articular syndrome. These are characterized by chronic or recurrent systemic inflammation associated with various clinical presentations, including urticaria-like rash, arthritis, sensorineural deafness, and central nervous system and bone involvement. In our review we focus on the clinical presentation of these diseases.

The diagnostic role of procalcitonin and other biomarkers in discriminating infectious from non-infectious fever

Fever is not only observed in the course of a bacterial or viral infection, but can be a symptom of, for instance, auto-immune, malignant or thromboembolic disease. Determining the etiology of fever in a fast and reliable way is of pivotal importance, as different causes of fever may ask for different therapies. Neither clinical signs and symptoms, nor traditional biomarkers, such as CRP, leukocytes and ESR have sufficient sensitivity and specificity to guide treatment decisions. In this review we focus on the value of traditional and newer biomarkers in non-infectious febrile diseases. Procalcitonin (PCT) seems to be the most helpful laboratory marker for the differentiation of causes of fever, particularly in autoimmune, autoinflammatory and malignant diseases.

Familial Mediterranean Fever as an Emerging Clinical Model of Atherogenesis Associated with Low-Grade Inflammation

Numerous inflammatory and innate immune pathways are involved in atherogenesis. Elaboration of clinical models of inflammation-induced atherogenesis may further advance our knowledge of multiple inflammatory pathways implicated in atherogenesis and provide a useful tool for cardiovascular prevention. Familial Mediterranean fever (FMF) is a chronic inflammatory disorder with profiles of inflammatory markers close to that seen in the general population. In a few recent studies, it has been shown that endothelial dysfunction, increased atherosclerotic burden and activation of platelets accompany attack-free periods of FMF. Colchicine is proved to be useful in suppression of inflammation in FMF. Preliminary basic and clinical studies suggest that this relatively safe drug may be useful for cardiovascular protection in patients with FMF and in the general population. Multinational prospective studies are warranted to further elaborate clinical model of inflammation-induced atherosclerosis associated with FMF.

Familial mediterranean Fever as an emerging clinical model of atherogenesis associated with low-grade inflammation

Numerous inflammatory and innate immune pathways are involved in atherogenesis. Elaboration of clinical models of inflammation-induced atherogenesis may further advance our knowledge of multiple inflammatory pathways implicated in atherogenesis and provide a useful tool for cardiovascular prevention. Familial Mediterranean fever (FMF) is a chronic inflammatory disorder with profiles of inflammatory markers close to that seen in the general population. In a few recent studies, it has been shown that endothelial dysfunction, increased atherosclerotic burden and activation of platelets accompany attack-free periods of FMF. Colchicine is proved to be useful in suppression of inflammation in FMF. Preliminary basic and clinical studies suggest that this relatively safe drug may be useful for cardiovascular protection in patients with FMF and in the general population. Multinational prospective studies are warranted to further elaborate clinical model of inflammation-induced atherosclerosis associated with FMF.

[Young woman with relapsing arthritis]

A 28-years old lady complains of self-limited episodes of relapsing knee arthritis of 48-72h of duration every 2 weeks. Immunological profile was all negative. At the same time, radiological images did not reveal any abnormality. She underwent to knee arthroscopy, however, a definite diagnosis was not reached. We discuss the differential diagnosis of relapsing arthritis.