From the Mediterranean to the sea of Japan: the transcontinental odyssey of autoinflammatory diseases

A Potential Partnership between Genetics and the Oral Microbiome in Children Displaying Periodic Fever/Aphthosis/Pharyngitis/Adenitis Syndrome

Periodic fever/aphthosis/pharyngitis/adenitis (PFAPA) syndrome was initially described in a small cohort of American children [...].

An Update on Familial Mediterranean Fever

(1) Background: Familial Mediterranean Fever (FMF) is the prototypal autoinflammatory disease, characterized by recurrent bursts of neutrophilic inflammation. (2) Methods: In this study we look at the most recent literature on this condition and integrate it with novel information on treatment resistance and compliance. (3) Results: The canonical clinical presentation of FMF is in children with self-limited episodes of fever and polyserositis, associated with severe long-term complications, such as renal amyloidosis. It has been described anecdotally since ancient times, however only recently it has been characterized more accurately. We propose an updated overview on the main aspects of pathophysiology, genetics, diagnosis and treatment of this intriguing disease. (4) Conclusions: Overall, this review presents the all the main aspects, including real life outcome of the latest recommendation on treatment resistance of FMF, a disease, that not only helped understanding the pathophysiology of the auto inflammatory process but also the functioning of the innate immune system itself.

An Update on Reports of Atypical Presentations of Kawasaki Disease and the Recognition of IVIG Non-Responder Children

Kawasaki disease (KD) is an acute vasculitis with an intrinsic risk of severe involvement of coronary arteries. The worldwide spread of KD and the importance of early diagnosis for preventing cardiovascular complications have ascertained the need for updating guidelines for prompt disease recognition and treatment efficacy assessment. All KD patients who comply with the definition of classic or atypical disease should be treated with intravenous immunoglobulin (IVIG) soon after diagnosis. The objective of our narrative review was to analyze the medical literature about case reports with atypical KD in relation to diagnosis and potential identification of predictors of non-responsiveness to IVIG. Our analysis has shown that the seminal challenge in KD management is the timeliness of diagnosis, although both extreme variability and transience of clinical manifestations make this goal difficult. A non-negligible percentage of patients, especially in the first 6 months of life, might have atypical manifestations of KD, whose painstaking differential diagnosis may be tricky. Many attempts to develop universal scoring systems and detect children at higher risk of IVIG resistance have been rather unsuccessful. Additionally, KD may show different evolutions according to unraveled demographic, genetic, or epigenetic factors. Further research is needed to elucidate all open questions about KD and clarify the long-term outcome of its potential complications.

Comparing biologic options for the management of Behcet's disease-related uveitis

INTRODUCTION

Behçet's disease (BD) associated uveitis occurs in approximately 50-70% of the patients. Ocular involvement in BD may induce a severe affection of visual function, leading to a considerable decrease in patients' quality of life. The risk for severe visual loss increases when the ocular posterior segment is involved and in patients with no adequate treatment.

AREAS COVERED

Monoclonal tumor necrosis factor (TNF) biotechnological inhibitors represent a relatively recent milestone for the treatment of non-infectious uveitis (NIU) also in BD patients. In addition to TNF inhibitors, further biologic agents have been increasingly proposed for multi-recalcitrant cases, as for interleukin (IL)-1 and IL-6 inhibitors. However, evidence on these new opportunities requires to be widened in the next future.

EXPERT OPINION

Joining the forces for scientific efforts is essential to quickly obtain solid acquisitions useful for the everyday clinical practice. To this end, the Auto-Inflammatory Disease Alliance (AIDA) Network has recently supported the development of an international registry dedicated to NIU and other inflammatory ocular involvement observed in BD patients. This will be essential to resolve current and future unmet needs burdening the everyday clinical practice.

Current Evidence on Vaccinations in Pediatric and Adult Patients with Systemic Autoinflammatory Diseases

Systemic autoinflammatory diseases (SAIDs) are defined by recurrent febrile attacks associated with protean manifestations involving joints, the gastrointestinal tract, skin, and the central nervous system, combined with elevated inflammatory markers, and are caused by a dysregulation of the innate immune system. From a clinical standpoint, the most known SAIDs are familial Mediterranean fever (FMF); cryopyrin-associated periodic syndrome (CAPS); mevalonate kinase deficiency (MKD); and periodic fever, aphthosis, pharyngitis, and adenitis (PFAPA) syndrome. Current guidelines recommend the regular sequential administration of vaccines for all individuals with SAIDs. However, these patients have a much lower vaccination coverage rates in 'real-world' epidemiological studies than the general population. The main purpose of this review was to evaluate the scientific evidence available on both the efficacy and safety of vaccines in patients with SAIDs. From this analysis, neither serious adverse effects nor poorer antibody responses have been observed after vaccination in patients with SAIDs on treatment with biologic agents. More specifically, no new-onset immune-mediated complications have been observed following immunizations. Post-vaccination acute flares were significantly less frequent in FMF patients treated with colchicine alone than in those treated with both colchicine and canakinumab. Conversely, a decreased risk of SARS-CoV-2 infection has been proved for patients with FMF after vaccination with the mRNA-based BNT162b2 vaccine. Canakinumab did not appear to affect the ability to produce antibodies against non-live vaccines in patients with CAPS, especially if administered with a time lag from the vaccination. On the other hand, our analysis has shown that immunization against Streptococcus pneumoniae, specifically with the pneumococcal polysaccharide vaccine, was associated with a higher incidence of adverse reactions in CAPS patients. In addition, disease flares might be elicited by vaccinations in children with MKD, though no adverse events have been noted despite concurrent treatment with either anakinra or canakinumab. PFAPA patients seem to be less responsive to measles, mumps, and rubella-vaccine, but have shown higher antibody response than healthy controls following vaccination against hepatitis A. In consideration of the clinical frailty of both children and adults with SAIDs, all vaccinations remain 'highly' recommended in this category of patients despite the paucity of data available.

Preliminary data revealing efficacy of Streptococcus salivarius K12 (SSK12) in Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis (PFAPA) syndrome: A multicenter study from the AIDA Network PFAPA syndrome registry

Objective

To evaluate the potential role of Streptococcus salivarius K12 (SSK12) in controlling febrile flares in patients with Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis (PFAPA) syndrome. Further aims were to assess the impact of SSK12 on (i) flare duration, (ii) variation in the degree of the highest body temperature during flares, (iii) steroid-sparing effect, and (iv) change of PFAPA accompanying symptoms before and after SSK12 introduction.

Patients and methods

The medical charts from 85 pediatric patients with PFAPA syndrome (49 males and 36 females) enrolled in the AIDA registry and treated with SSK12 for a median period of 6.00 ± 7.00 months in the period between September 2017 and May 2022 were examined. Children recruited had a median time of disease duration of 19.00 ± 28.00 months.

Results

The number of febrile flares significantly decreased comparing the 12 months before [median (IQR), 13.00 (6.00)] and after SSK12 initiation [median (IQR), 5.50 (8.00), p < 0.001]. The duration of fever was significantly reduced from 4.00 (2.00) days to 2.00 (2.00) days [p < 0.001]. Similarly, the highest temperature in°C was found significantly lower in the last follow-up assessment [median (IQR), 39.00 (1.00)] compared to the period prior to SSK12 start [median (IQR), 40.00 (1.00), p < 0.001]. Steroid load (mg/year) of betamethasone (or any equivalent steroid) significantly decreased between 12 months before treatment with SSK12 [median (IQR), 5.00 (8.00) mg/year] and the last follow-up visit [median (IQR), 2.00 (4.00) mg/year, p < 0.001]. The number of patients experiencing symptoms including pharyngitis/tonsillitis (p < 0.001), oral aphthae (p < 0.001) and cervical lymphadenopathy (p < 0.001) significantly decreased following SSK12.

Conclusion

SSK12 prophylaxis given for at least 6.00 months was found to reduce febrile flares of PFAPA syndrome: in particular, it halved the total number per year of fever flares, shortened the duration of the single febrile episode, lowered body temperature by 1°C in the febrile flare, provided a steroid-sparing effect, and significantly reduced the accompanying symptoms related to the syndrome.

The Autoinflammatory Diseases Alliance Registry of monogenic autoinflammatory diseases

Objective

The present manuscript aims to describe an international, electronic-based, user-friendly and interoperable patient registry for monogenic autoinflammatory diseases (mAIDs), developed in the contest of the Autoinflammatory Diseases Alliance (AIDA) Network.

Methods

This is an electronic platform, based on the Research Electronic Data Capture (REDCap) tool, used for real-world data collection of demographics, clinical, laboratory, instrumental and socioeconomic data of mAIDs patients. The instrument has flexibility, may change over time based on new scientific acquisitions, and communicate potentially with other similar registries; security, data quality and data governance are corner stones of the platform.

Results

AIDA project will share knowledge and expertise on mAIDs. Since its start, 118 centers from 24 countries and 4 continents have joined the AIDA project. Fifty-nine centers have already obtained the approval from their local Ethics Committees. Currently, the platform counts 337 users (122 Principal Investigators, 210 Site Investigators, 2 Lead Investigators, and 3 data managers). The Registry collects baseline and follow-up data using 3,748 fields organized into 21 instruments, which include demographics, patient history, symptoms, trigger/risk factors, therapies, and healthcare information for mAIDs patients.

Conclusions

The AIDA mAIDs Registry, acts both as a research tool for future collaborative real-life studies on mAIDs and as a service to connect all the figures called to participate. On this basis, the registry is expected to play a pivotal role in generating new scientific evidence on this group of rare diseases, substantially improving the management of patients, and optimizing the impact on the healthcare system. NCT 05200715 available at https://clinicaltrials.gov.

The Clinical Chameleon of Autoinflammatory Diseases in Children

The very first line of defense in humans is innate immunity, serving as a critical strongpoint in the regulation of inflammation. Abnormalities of the innate immunity machinery make up a motley group of rare diseases, named ‘autoinflammatory’, which are caused by mutations in genes involved in different immune pathways. Self-limited inflammatory bouts involving skin, serosal membranes, joints, gut and other districts of the human body burst and recur with variable periodicity in most autoinflammatory diseases (ADs), often leading to secondary amyloidosis as a long-term complication. Dysregulated inflammasome activity, overproduction of interleukin (IL)-1 or other IL-1-related cytokines and delayed shutdown of inflammation are pivotal keys in the majority of ADs. The recent progress of cellular biology has clarified many molecular mechanisms behind monogenic ADs, such as familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome (or ‘autosomal dominant familial periodic fever’), cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, hereditary pyogenic diseases, idiopathic granulomatous diseases and defects of the ubiquitin-proteasome pathway. A long-lasting history of recurrent fevers should require the ruling out of chronic infections and malignancies before considering ADs in children. Little is known about the potential origin of polygenic ADs, in which sterile cytokine-mediated inflammation results from the activation of the innate immunity network, without familial recurrency, such as periodic fever/aphthous stomatitis/pharyngitis/cervical adenopathy (PFAPA) syndrome. The puzzle of febrile attacks recurring over time with chameleonic multi-inflammatory symptoms in children demands the inspection of the mixture of clinical data, inflammation parameters in the different disease phases, assessment of therapeutic efficacy of a handful of drugs such as corticosteroids, colchicine or IL-1 antagonists, and genotype analysis to exclude or confirm a monogenic origin.

Development and implementation of the AIDA International Registry for patients with Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis syndrome

OBJECTIVE

Aim of this paper is to illustrate the methodology, design, and development of the AutoInflammatory Disease Alliance (AIDA) International Registry dedicated to patients with the Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis (PFAPA) syndrome.

METHODS

This is a physician-driven, non-population- and electronic-based registry proposed to gather real-world demographics, clinical, laboratory, instrumental and socioeconomic data from PFAPA patients. Data recruitment is realized through the on-line Research Electronic Data Capture (REDCap) tool. This registry is thought to collect standardized information for clinical research leading to solid real-life evidence. The international scope and the flexibility of the registry will facilitate the realization of cutting-edge study projects through the constant updating of variables and the possible merging and transfer of data between current and future PFAPA registries.

RESULTS

A total of 112 centers have already been involved from 23 countries and 4 continents starting from August 24th, 2021, to April 6th, 2022. In total 56/112 have already obtained the formal approval from their local Ethics Committees. The platform counts 321 users (113 principal investigators, 203 site investigators, two lead investigators, and three data managers). The registry collects retrospective and prospective data using 3,856 fields organized into 25 instruments, including PFAPA patient's demographics, medical histories, symptoms, triggers/risk factors, therapies, and impact on the healthcare systems.

CONCLUSIONS

The development of the AIDA International Registry for PFAPA patients will enable the on-line collection of standardized data prompting real-life studies through the connection of worldwide groups of physicians and researchers. This project can be found on https://clinicaltrials.gov NCT05200715.

Clinical profile and evolution of patients with juvenile-onset Behçet's syndrome over a 25-year period: insights from the AIDA network

Behçet's syndrome (BS) represents an understudied topic in pediatrics: the main aims of our study were to characterize demographic and clinical features of a cohort of BS patients with juvenile-onset managed in three tertiary referral centers in Italy, evaluate their evolution in the long-term, and detect any potential differences with BS patients having an adult-onset. Medical records of 64 juvenile-onset and 332 adult-onset BS followed-up over a 2-year period were retrospectively analyzed and compared. Mean age ± SD of first symptom-appearance was 10.92 ± 4.34 years with a female-to-male ratio of 1.06:1. Mucocutaneous signs were the most frequent initial manifestations, followed by uveitis. Throughout the disease course, genital aphthae (76.56%) and pseudofolliculitis (40.63%) prevailed among the mucocutaneous signs, while major organ involvement was represented by gastrointestinal and ocular involvement (43.75 and 34.38%, respectively). No significant differences emerged for both mucocutaneous signs and specific major organ involvement between juvenile-onset and adult BS patients. After excluding nonspecific abdominal pain, juvenile-onset BS patients were less frequently characterized by the development of major organ involvement (p = 0.027). Logistic regression detected the juvenile-onset as a variable associated with reduced risk of long-term major organ involvement (OR 0.495 [0.263-0.932], p = 0.029). In our cohort, juvenile-onset BS resembled the clinical spectrum of adult-onset patients. Pediatric patients with a full-blown disease at onset showed a more frequent mucocutaneous involvement. In addition, patients with juvenile-onset seemed to develop less frequently major organ involvement and had an overall less severe disease course.

The everchanging framework of autoinflammation

The innate immunity works as a defence bullwark that safeguards healthy tissues with the power of detecting infectious agents in the human body: errors in the context of innate immunity identify autoinflammatory disorders (AIDs), which arise as bouts of aberrant inflammation with little or no involvement of T and B cells and neither recognized infections, nor associated autoimmune phenomena. Hereditary AIDs tend to have a pediatric-onset heralded by stereotyped inflammatory symptoms and fever, while AIDs without an ascertained cause, such as systemic juvenile idiopathic arthritis, derive from the interaction of genetic factors with environmental noxae and are unevenly defined. A dysregulated inflammasome activation promotes the best-known family of AIDs, as well as several degenerative and metabolic disorders, but also nuclear factor κB- and interferon-mediated conditions have been framed as AIDs: the zenith of inflammatory flares marks different phenotypes, but diagnosis may go unnoticed until adulthood due to downplayed symptoms and complex kaleidoscopic presentations. This review summarizes the main AIDs encountered in childhood with special emphasis on the clinical stigmata that may help establish a correct framework and blueprints to empower young scientists in the recognition of AIDs. The description focuses inflammasomopathies as paradigms of interleukinopathies, nuclear factor-κB -related disorders and interferonopathies. The challenges in the management of AIDs during childhood have been recently boosted by numerous therapeutic options derived from genomically-based approaches, which have led to identify targeted biologic agents as rationalized treatments and achieve more tangible perspectives of disease control.

Early introduction of anakinra improves acute pericarditis and prevents tamponade in Staphylococcal sepsis

The clinical response to anakinra observed by this patient concurrently treated with antibiotics indirectly confirms the potentially pathogenic role of IL-1 in maintaining the pericardial disease and shows how IL-1 blockade might allow avoiding the pericardiocentesis procedure. The report supports the hypothesis that anakinra is an effective and safe tool in the early treatment of acute pericarditis of presumed bacterial origin nonresponding to targeted antibiotic therapy.

Drug survival of anakinra and canakinumab in monogenic autoinflammatory diseases: observational study from the International AIDA Registry

OBJECTIVES

To investigate survival of interleukin (IL)-1 inhibitors in monogenic autoinflammatory disorders (mAID) through drug retention rate (DRR) and identify potential predictive factors of drug survival from a real-life perspective.

PATIENTS AND METHODS

Multicentre retrospective study analyzing patients affected by the most common mAID treated with anakinra or canakinumab. Survival curves were analyzed with the Kaplan-Meier method. Statistical analysis included a Cox-proportional hazard model to detect factors responsible for drug discontinuation.

RESULTS

Seventy-eight patients for a total of 102 treatment regimens were enrolled. The mean treatment duration was 29.59 months. The estimated DRR of IL-1 inhibitors at 12, 24, and 48 months of follow-up was 75.8%, 69.7% and 51.1%, respectively. Patients experiencing an adverse event had a significantly lower DRR (p = 0.019). In contrast, no significant differences were observed between biologic-naïve patients and those previously treated with biologic drugs (p = 0.985) Patients carrying high-penetrance mutations exhibited a significantly higher DRR compared with those with low-penetrance variants (p = 0.015). Adverse events were the only variable associated with a higher hazard of treatment withdrawal (HR 2.573 [CI: 1.223-5.411], p = 0.013) on regression analysis. A significant glucorticoid-sparing effect was observed (p < 0.0001).

CONCLUSIONS

IL-1 inhibitors display an excellent long-term effectiveness in terms of DRR, and their survival is not influenced by the biologic line of treatment. They display a favorable safety profile, that deserves however a close monitoring given its impact on treatment continuation. Special attention should be paid to molecular diagnosis and mutation penetrance, as patients carrying low-penetrance variants are more likely to interrupt treatment.

Overview of the rarest causes of fever in newborns: handy hints for the neonatologist

Neonatal causes of fever are a major source of concern for clinicians. If fever is combined with organ-specific sterile inflammatory manifestations the suspicion of autoinflammatory disorders should be considered, and the list of such conditions starting in the neonatal period includes chronic infantile neurological cutaneous articular syndrome, mevalonate kinase deficiency, deficiency of the interleukin-1 receptor antagonist, otulipenia, STING-associated vasculopathy with onset in infancy and Blau syndrome. Other causes of noninfectious fever that can rarely occur in newborns are Kawasaki disease, Behçet's disease, and hemophagocytic lymphohistiocytosis. Diagnosis of these exceptionally rare disorders is challenging for neonatologists. An early recognition of these complex diseases might lead to use more specific or rational drugs preventing permanent consequences. This review focuses on the rarest causes of fever occurring in the neonatal age with the aim of portraying many protean clinical pictures associated with fever and reviewing the potential available treatments.

Children and Adults with PFAPA Syndrome: Similarities and Divergences in a Real-Life Clinical Setting

INTRODUCTION

Analogies or differences of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome in children and adults are barely known. The aim of our study was to compare the overall characteristics of a large cohort of patients, both children and adults, diagnosed with PFAPA syndrome.

METHODS

In the last decade, we identified 120 children and 63 adults with periodically recurring fevers, who fulfilled the criteria for PFAPA diagnosis. The two subcohorts were analyzed according to demographic features, clinical manifestations, laboratory data, and responses to therapies.

RESULTS

The mean age of onset was 2.4 ± 1.5 and 19.7 ± 10.3 years, respectively, in children and adults, while attacks occurred every 3.8 ± 0.8 and every 4.3 ± 2.3 weeks, respectively, in children and adults. A higher prevalence of exudative pharyngitis was observed in children (58.8%), and the majority of children had only two cardinal signs during flares. In adults, there was a higher interpersonal variability of the intercritical periods. Inflammatory markers measured during non-febrile periods were normal in children but altered in the totality of adults during febrile periods. A strong efficacy of corticosteroids in controlling the pediatric syndrome was observed, but response rates to steroids were less brilliant in adults. Colchicine and interleukin-1 inhibitors were used in the management of the steroid-resistant adult syndrome. Conversely, tonsillectomy was performed in a very low number of children, but was effective in 60.7% of adults when treated after 16 years. The mean age of disappearance of PFAPA symptoms has been 6.4 ± 2.4 years in children, while only 27% of adults have shown a complete drug-free symptom regression.

CONCLUSIONS

A linear conformity of the PFAPA syndrome has been observed between pediatric and adult patients. PFAPA symptoms tended to disappear with no sequelae in 94.1% of children, while the disease was still active in almost 3/4 of adults at the time of our assessment.

Revised recommendations of the Italian Society of Pediatrics about the general management of Kawasaki disease

Aim of these revised recommendations for the general management of Kawasaki disease is to encourage its prompter recognition and warrant the most appropriate therapy, based on ascertained scientific data, raising awareness of the complications related to misdiagnosis or delayed treatment. A set of 20 synthetic operative statements is herein provided, including the definition of Kawasaki disease, its protean presentations, clinical course and seminal treatment modalities of all disease phases. The application of these recommendations should improve prognosis of Kawasaki disease and prevent the progression to permanent vascular abnormalities, thereby diminishing morbidity and mortality.

Safety of systemic treatments for Behçet's syndrome

INTRODUCTION

Treatment of Behçet's syndrome (BS) is aimed at controlling all symptoms of such a complex disorder, ensuring a good quality of life and preventing life-threatening complications. A better understanding of the pathogenic role of different chemokines has improved our knowledge of BS and elicited a more specific use of therapies currently available, minimizing the burden of potential side-effects related to treatment.

AREAS COVERED

This work aims to provide a detailed overview of the safety profile for current therapies available in the treatment of BS, focusing on the main side-effects, toxicity and contraindications.

EXPERT OPINION

The greatest experience in the management of BS has been achieved with the employment of monoclonal anti-tumor necrosis factor antibodies which have been advocated for BS refractory manifestations. Moreover, interleukin-1 inhibitors have proven to be effective as well as safe, despite escalation of their dosage, especially to manage the most severe and difficult-to-treat ocular manifestations. However, general treatment of BS patients remains awkward as protean clinical features may respond differently to the same treatment or even worsen. Therefore, patients' safety for therapies used in BS promotes the implementation of precision medicine, which could help targeting accurately the pathogenetic mechanisms concealed behind specific clinical phenotypes.

Improvement of Liver Involvement in Familial Mediterranean Fever After the Introduction of Canakinumab: A Case Report

Hepatic involvement in familial Mediterranean fever (FMF) ranges from a nonspecific increase in liver enzymes to cryptogenic cirrhosis, and the liver is mostly involved in patients bearing the M694V MEFV mutation in homozygosis. A 44-year-old Jewish woman with FMF developed nonalcoholic steatohepatitis during colchicine treatment (2,5 mg per day), confirmed by both elastography and liver biopsy. Therefore, combined therapy with the interleukin-1 (IL-1) blocking agent canakinumab (150 mg every four weeks) and colchicine (at a reduced dose of 1.5 mg per day) was started. Three months later, transaminases became normal, and after further six months, there was a marked improvement of liver fibrosis. IL-1 blockade has the power to halt or mitigate liver involvement in FMF patients. However, further experience is required to assess its therapeutic potential in the most severe patients with the hepatic disease who are partially responsive to long-term prophylaxis with colchicine.

Phenotype variability of autoinflammatory disorders in the pediatric patient: A pictorial overview

Disruption of innate immunity leading to systemic inflammation and multi-organ dysfunction is the basilar footprint of autoinflammatory disorders (AIDs), ranging from rare hereditary monogenic diseases to a large number of common chronic inflammatory conditions in which there is a simultaneous participation of multiple genetic components and environmental factors, sometimes combined with autoimmune phenomena and immunodeficiency. Whatever their molecular mechanism, hereditary AIDs are caused by mutations in regulatory molecules or sensors proteins leading to dysregulated production of proinflammatory cytokines or cytokine-inducing transcription factors, fever, elevation of acute phase reactants, and a portfolio of manifold inflammatory signs which might occur in a stereotyped manner, mostly with overactivity or misactivation of different inflammasomes. Symptoms might overlap in the pediatric patient, obscuring the final diagnosis of AIDs and delaying the most appropriate treatment. Actually, the fast-paced evolution of scientific knowledge has led to recognize or reclassify an overgrowing number of multifactorial diseases, which share the basic pathogenetic mechanisms with AIDs. The wide framework of classic hereditary periodic fevers, AIDs with prominent skin involvement, disorders of the ubiquitin-proteasome system, defects of actin cytoskeleton dynamics, and also idiopathic nonhereditary febrile syndromes occurring in children is herein presented. Interleukin-1 dependence of these diseases or involvement of other predominating molecules is also discussed.

Kawasaki Disease as the Immune-Mediated Echo of a Viral Infection

Although the etiology of Kawasaki disease (KD) remains elusive, the available evidence indicates that the primum movens may be a dysregulated immune response to various microbial agents, leading to cytokine cascade and endothelial cell activation in patients with KD. Documented infections by different viruses in many individual cases have been largely reported and are discussed herein, but attempts to demonstrate their causative role in the distinctive KD scenario and KD epidemiological features have been disappointing. To date, no definite link has been irrefutably found between a single infection and KD.

A new report of autoinflammation and PLCG2-associated antibody deficiency and immune dysregulation (APLAID) with a homozygous pattern from Iran

Autoinflammation and PLCG2-associated antibody deficiency and immune dysregulation (APLAID) is an autosomal dominant autoinflammatory disease characterized by episodic skin, musculoskeletal, ophthalmic and gastrointestinal tract symptoms. Here we report an 11-year-old girl with a history of repeated episodes of fever, myalgia, arthralgia, abdominal pain, and urticarial rash in the trunk and limbs. Chest and pelvic X-Ray, sacroiliac joints MRI, brain MRI and abdominal CT scan were normal. Anti-nuclear antibody, Rheumatoid factor, cryoglobulin, ANCA/PR3, p-ANCA/MPO, anti-smooth muscle antibody and anti-mitochondrial antibody were negative. Serology for cytomegalovirus, Epstein-Barr, hepatitis B, hepatitis C, and HIV viruses was negative. Serum immunoglobulins were in the normal range. Genetic analysis for familial Mediterranean fever syndrome was negative. Whole exome sequencing was carried out to identify the genetic cause of our patient. We identified a homozygous missense variant (c.579C > G, p. His193Gln) in exon 7 of the PLCG2 gene. Bioinformatic analysis and clinical symptoms suggests this variant to be pathogenic in the homozygous state for APLAID and thus probably acting in an autosomal recessive manner. Our bioinformatic analysis also showed this novel mutation to have detrimental effects on the 3D structure of the PLCG2 protein, which is well conserved among many other similar species.

Hints for Genetic and Clinical Differentiation of Adult-Onset Monogenic Autoinflammatory Diseases

Monogenic autoinflammatory diseases (mAIDs) are inherited errors of innate immunity characterized by systemic inflammation recurring with variable frequency and involving the skin, serosal membranes, synovial membranes, joints, the gastrointestinal tube, and/or the central nervous system, with reactive amyloidosis as a potential severe long-term consequence. Although individually uncommon, all mAIDs set up an emerging chapter of internal medicine: recent findings have modified our knowledge regarding mAID pathophysiology and clarified that protean inflammatory symptoms can be variably associated with periodic fevers, depicting multiple specific conditions which usually start in childhood, such as familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, cryopyrin-associated periodic syndrome, and mevalonate kinase deficiency. There are no evidence-based studies to establish which potential genotype analysis is the most appropriate in adult patients with clinical phenotypes suggestive of mAIDs. This review discusses genetic and clinical hints for an ideal diagnostic approach to mAIDs in adult patients, as their early identification is essential to prompt effective treatment and improve quality of life, and also highlights the most recent developments in the diagnostic work-up for the most frequent hereditary periodic febrile syndromes worldwide.

Familial Mediterranean Fever: Assessing the Overall Clinical Impact and Formulating Treatment Plans

Recurrent self-limited attacks of fever and short-lived inflammation in the serosal membranes, joints, and skin are the leading features of familial Mediterranean fever (FMF), the most common autoinflammatory disorder in the world, transmitted as autosomal recessive trait caused by MEFV gene mutations. Their consequence is an abnormal function of pyrin, a natural repressor of inflammation, apoptosis, and release of cytokines. FMF-related mutant pyrins are hypophosphorylated following RhoA GTPases’ impaired activity and show a propensity to relapsing uncontrolled systemic inflammation with inappropriate response to inflammatory stimuli and leukocyte spread to serosal membranes, joints or skin. Typical FMF phenotype 1 consists of brief episodes of inflammation and serositis, synovitis, and/or erysipelas-like eruption, whereas phenotype 2 is defined by reactive amyloid-associated (AA) amyloidosis, which is the most ominous complication of FMF, in otherwise asymptomatic individuals.

Furthermore, FMF phenotype 3 is referred to the presence of two MEFV mutations with neither clinical signs of FMF nor AA amyloidosis. The influence of epigenetic and/or environmental factors can contribute to the variable penetrance and phenotypic heterogeneity of FMF. Colchicine, a tricyclic alkaloid with anti-microtubule and anti-inflammatory properties, is the bedrock of FMF management: daily administration of colchicine prevents the recurrence of FMF attacks and the development of secondary AA amyloidosis. Many recent studies have also shown that anti-interleukin-1 treatment is the best therapeutic option for FMF patients nonresponsive or intolerant to colchicine. This review aims to catch readers’ attention to the clinical diversity of phenotypes, differential diagnosis, and management of patients with FMF.

The Broad-Ranging Panorama of Systemic Autoinflammatory Disorders with Specific Focus on Acute Painful Symptoms and Hematologic Manifestations in Children

Systemic autoinflammatory disorders (SAIDs) are inherited defects of innate immunity characterized by recurrent sterile inflammatory attacks involving skin, joints, serosal membranes, gastrointestinal tube, and other tissues, which recur with variable rhythmicity and display reactive amyloidosis as a potential long-term complication. Dysregulated inflammasome activity leading to overproduction of many proinflammatory cytokines, such as interleukin-1 (IL-1), and delayed shutdown of inflammation are considered crucial pathogenic keys in the vast majority of SAIDs. Progress of cellular biology has partially clarified the mechanisms behind monogenic SAIDs, such as familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, hereditary pyogenic diseases, idiopathic granulomatous diseases and defects of the ubiquitin-proteasome pathway. Whereas, little is clarified for the polygenic SAIDs, such as periodic fever, aphthous stomatitis, pharyngitis, and cervical adenopathy (PFAPA) syndrome. The puzzle of symptomatic febrile attacks recurring over time in children requires evaluating the mixture of clinical data, inflammatory parameters in different disease phases, the therapeutic efficacy of specific drugs such as colchicine, corticosteroids or IL-1 antagonists, and genotype analysis in selected cases. The long-term history of periodic fevers should also need to rule out chronic infections and malignancies. This review is conceived as a practical template for proper classification of children with recurring fevers and includes tips useful for the diagnostic approach to SAIDs, focusing on the specific acute painful symptoms and hematologic manifestations encountered in childhood.

New mosaic tiles in childhood hereditary autoinflammatory disorders

The protean clinical phenotypes of hereditary autoinflammatory disorders (HAID) are caused by abnormal activation of innate immunity and consist of seemingly unprovoked inflammatory flares localized to multiple organs, such as the skin, joints, serosal membranes, gut, and central nervous system. Different mutations in genes implied in activation of the interleukin-1 (IL-1)-structured inflammasome, cytoskeletal signaling and apoptosis contribute to the pathogenesis of different HAID, which mostly start in childhood with self-limited flares unrelated to infectious agents, autoantibody production or autoreactive cells. Though IL-1 remains pivotal in many inflammasome-mediated diseases, other cytokinopathies involving IL-18, nuclear factorκ-B, interferons, and tumor necrosis factor have provided new horizons in the definition of HAID of children: the list of HAID has expanded as a consequence of a better understanding of their pathogenetic molecular mechanisms and also application of new genetic technologies. However, diagnosis of most HAID is clinical and focused on several evidence-based criteria sets: their discrimination remains challenging for unexperienced pediatricians as there are no universally accepted algorithms, and a still relevant number of patients may linger without any clarifying genetic analysis, whose interpretation combined with processing of treatment options should be discussed on a multidisciplinary basis.

The diagnostic evaluation of patients with a suspected hereditary periodic fever syndrome: experience from a referral center in Italy

The study aims are to describe the activity of our Unit on the diagnostics of monogenic autoinflammatory diseases (AIDs), and to apply the clinical classification criteria for periodic fevers from the Eurofever Registry to our cohort of patients, thus evaluating their usefulness in the real life. We retrospectively analyzed data from patients referring to our Center for recurrent fever attacks, and undergoing genetic analysis between April 2014 and July 2016, and we applied the classification criteria to both genetically positive and -negative patients. We visited 195 patients (101 females, 94 males); 126 (64.6%) were adults and 192 (98.5%) Caucasians; 12.3% carried mutations and 12.7% of adults were genetically positive. No statistically significant differences were identified in the frequency of genetic diagnosis between adults and children (p = 0.82) as well as in the frequency of genetic diagnosis, based on the number of genes evaluated (p = 0.57). When we applied the Eurofever criteria, 126/195 (64.6%) patients were classified for at least one among the four main monogenic AIDs; 22 (11.3%) patients fulfilled criteria for 2 diseases and 4 (2.1%) for 3 diseases. Among patients carrying mutations, 12/24 (50%) correctly fulfilled the score, 3/24 (12.5%) fulfilled criteria differently from their genetic diagnosis; 9/22 (40.9%) recieved no classification. An expanded genetic testing does not seem useful, while a correct interpretation of patients' clinical picture may allow performing specific genetic testing. The classification criteria from the Eurofever Registry have shown to be a beneficial tool in the evaluation of patients with a suspected monogenic AID.

Lung Involvement in Children with Hereditary Autoinflammatory Disorders

Short-lived systemic inflammatory reactions arising from disrupted rules in the innate immune system are the operating platforms of hereditary autoinflammatory disorders (HAIDs). Multiple organs may be involved and aseptic inflammation leading to disease-specific phenotypes defines most HAIDs. Lungs are infrequently involved in children with HAIDs: the most common pulmonary manifestation is pleuritis in familial Mediterranean fever (FMF) and tumor necrosis factor receptor-associated periodic syndrome (TRAPS), respectively caused by mutations in the MEFV and TNFRSF1A genes, while interstitial lung disease can be observed in STING-associated vasculopathy with onset in infancy (SAVI), caused by mutations in the TMEM173 gene. The specific pleuropulmonary diseases may range from sub-clinical abnormalities during inflammatory flares of FMF and TRAPS to a severe life-threatening disorder in children with SAVI.

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

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

Lights and shadows in autoinflammatory syndromes from the childhood and adulthood perspective

In a high percentage of cases, the monogenic autoinflammatory syndromes (AIS), caused by subversion in the inflammasome homeostasis leading to cytokine oversecretion and characterized by multiple inflammatory pictures, start in childhood. However, the description of tardive manifestations, veiled phenotypes, and atypical clinical signs beginning in adulthood has been more and more reported in recent times, requiring that many specialists become confident with concepts, details, and management strategies of AIS. Differences between child- and adult-onset syndromes raise the question of whether pathogenic mechanisms might differ when the timetable of AIS onset diverges, but show that carefulness is needed to establish a straightforward diagnosis.

Macrophage activation syndrome in the course of monogenic autoinflammatory disorders

An overwhelming activation of cytotoxic T cells and well-differentiated macrophages leading to systemic overload of inflammatory mediators characterizes the so-called macrophage activation syndrome (MAS); this potentially life-threatening clinical entity may derive from several genetic defects involved in granule-mediated cytotoxicity but has been largely observed in patients with juvenile idiopathic arthritis, many rheumatologic diseases, infections, and malignancies. The occurrence of MAS in the natural history or as the revealing clue of monogenic autoinflammatory disorders (AIDs), rare conditions caused by disrupted innate immunity pathways with overblown release of proinflammatory cytokines, has been only reported in few isolated patients with cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome since 2001. All these patients displayed various clinical, laboratory, and histopathologic features of MAS and have often required intensive care support. Only one patient has died due to MAS. Defective cytotoxic cell function was documented in a minority of patients. Corticosteroids were the first-line treatment, but anakinra was clinically effective in three refractory cases. Even if MAS and AIDs share multiple clinical features as well as heterogeneous pathogenetic scenes and a potential response to anti-interleukin-1 targeted therapies, MAS requires a prompt specific recognition in the course of AIDs due to its profound severity and high mortality rate.

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.

Non-canonical manifestations of familial Mediterranean fever: a changing paradigm

Paroxysmal crises of fever and systemic inflammation herald familial Mediterranean fever (FMF), considered as the archetype of all inherited systemic autoinflammatory diseases. Inflammatory bouts are characterized by short-term and self-limited abdominal, thoracic, and/or articular symptoms which subside spontaneously. Erysipelas-like findings, orchitis, and different patterns of myalgia may appear in a minority of patients. In recent years, many non-classical manifestations have been reported in the clinical context of FMF, such as vasculitides and thrombotic manifestations, neurologic and sensory organ abnormalities, gastrointestinal diseases, and even macrophage activation syndrome. As FMF left unrecognized and untreated is ominously complicated by the occurrence of AA-amyloidosis, it is highly desirable that diagnosis of this autoinflammatory disorder with its multiple clinical faces can be contemplated at whatever age and brought forward.

Current advances in the understanding and treatment of mevalonate kinase deficiency

Mevalonate kinase deficiency (MKD) is a rare autosomal recessive autoinflammatory metabolic disease that is caused by mutations in the MVK gene. Patients with MKD typically have an early onset in infancy. MKD is characterized by recurrent episodes of high fever, abdominal distress, diffuse joint pain, and skin rashes. In a subset of patients, MKD is also associated with elevated serum immunoglobulin D (IgD) levels (hyperimmunoglobulinemia D syndrome, HIDS). The clinical phenotype of MKD varies widely and depends on the severity of the impaired mevalonate kinase activity. Complete impairment results in the severe metabolic disease, mevalonic aciduria, while a partial deficiency results in a broad spectrum of clinical presentation, including HIDS. The precise molecular mechanisms behind the elevated serum IgD levels and inflammation that occurs in MKD remain unknown. Children who exhibit symptoms of MKD should be tested for mutations in the MKD gene. However, the complexity of MKD often results in delays in its definitive diagnosis and the outcome in adult age is not completely known. Therapeutic options for MKD are based on limited data and include non-steroidal anti-inflammatory drugs, corticosteroids, and biological agents that target specific cytokine pathways. In recent years, some studies have reported promising results for new biological drugs; however, these cases have failed to achieve satisfactory remission. Therefore, further studies are needed to understand the pathogenesis of MKD and identify innovative therapeutic tools for its management.

Interleukin-1 as a common denominator from autoinflammatory to autoimmune disorders: premises, perils, and perspectives

A complex web of dynamic relationships between innate and adaptive immunity is now evident for many autoinflammatory and autoimmune disorders, the first deriving from abnormal activation of innate immune system without any conventional danger triggers and the latter from self-/non-self-discrimination loss of tolerance, and systemic inflammation. Due to clinical and pathophysiologic similarities giving a crucial role to the multifunctional cytokine interleukin-1, the concept of autoinflammation has been expanded to include nonhereditary collagen-like diseases, idiopathic inflammatory diseases, and metabolic diseases. As more patients are reported to have clinical features of autoinflammation and autoimmunity, the boundary between these two pathologic ends is becoming blurred. An overview of monogenic autoinflammatory disorders, PFAPA syndrome, rheumatoid arthritis, type 2 diabetes mellitus, uveitis, pericarditis, Behçet's disease, gout, Sjögren's syndrome, interstitial lung diseases, and Still's disease is presented to highlight the fundamental points that interleukin-1 displays in the cryptic interplay between innate and adaptive immune systems.

Autoimmunity and autoinflammation as the yin and yang of idiopathic recurrent acute pericarditis

Autoimmunity and autoinflammation are generally considered as mutually exclusive mechanisms of diseases but may concur to specific syndromes. Idiopathic recurrent acute pericarditis (IRAP) is defined as the recurrence of pericardial symptoms at any point following the prior cessation of acute pericarditis, and the latency is generally 6 weeks. Manifestations of pericarditis such as pericardial friction rub, electrocardiographic changes, and pericardial effusion are less frequent in the subsequent episodes compared to the index attack, and in some cases the only clinical sign is represented by a suggestive chest pain. Several autoimmune diseases may manifest with pericarditis which is often related to viral infections, while postviral pericarditis may in turn display a nonspecific autoimmune background. Similarly, autoinflammatory syndromes such as familial Mediterranean fever and tumor necrosis factor receptor-associated periodic syndrome are characterized by self-limiting pericardial symptoms. Corticosteroids are generally effective, thus supporting the autoimmune nature of IRAP, but dramatic results are obtained with interleukin-1 blocking agents in corticosteroid-dependent cases, pointing to a pathogenic role for the inflammasome. Based on these observations, we submit that IRAP represents a paradigmatic example of the putative coexistence of autoimmunity and autoinflammation: the main aim of this review is to critically discuss the hypothesis as well as the current understanding of this enigmatic clinical condition.

Untangling the web of systemic autoinflammatory diseases

The innate immune system is involved in the pathophysiology of systemic autoinflammatory diseases (SAIDs), an enlarging group of disorders caused by dysregulated production of proinflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α, in which autoreactive T-lymphocytes and autoantibodies are indeed absent. A widely deranged innate immunity leads to overactivity of proinflammatory cytokines and subsequent multisite inflammatory symptoms depicting various conditions, such as hereditary periodic fevers, granulomatous disorders, and pyogenic diseases, collectively described in this review. Further research should enhance our understanding of the genetics behind SAIDs, unearth triggers of inflammatory attacks, and result in improvement for their diagnosis and treatment.

The labyrinth of autoinflammatory disorders: a snapshot on the activity of a third-level center in Italy

Autoinflammatory disorders (AIDs) are a novel class of diseases elicited by mutations in genes regulating the homeostasis of innate immune complexes, named inflammasomes, which lead to uncontrolled oversecretion of the proinflammatory cytokine interleukin-1β. Protean inflammatory symptoms are variably associated with periodic fever, depicting multiple specific conditions. Childhood is usually the lifetime in which most hereditary AIDs start, though still a relevant number of patients may experience a delayed disease onset and receive a definite diagnosis during adulthood. As a major referral laboratory for patients with recurrent fevers, we have tested samples from 787 patients in the period September 2007-March 2014, with a total of 1,328 AID-related genes evaluated and a gene/patient ratio of 1.69. In this report, we describe our experience in the clinical approach to AIDs, highlight the most striking differences between child and adult-onset AIDs, and shed an eye-opening insight into their diagnostic process.

Key facts and hot spots on tumor necrosis factor receptor-associated periodic syndrome

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS), formerly known as familial Hibernian fever, is the most common autosomal dominant autoinflammatory disease, resulting from mutations in the TNFRSF1A gene, encoding the 55-kD tumor necrosis factor receptor. The pathophysiologic mechanism of TRAPS remains ambiguous and only partially explained. The onset age of the syndrome is variable and the clinical scenery is characterized by recurrent episodes of high-grade fever that typically lasts 1-3 weeks, associated with migrating myalgia, pseudocellulitis, diffuse abdominal pain, appendicitis-like findings, ocular inflammatory signs, and risk of long-term amyloidosis. Fever episodes are responsive to high-dose corticosteroids, but different classes of drugs have been reported to be ineffective. The use of etanercept is unable to control systemic inflammation, while interleukin-1 blockade has been shown as effective in the control of disease activity in many patients reported so far.

Inhibition of interleukin-1 by canakinumab as a successful mono-drug strategy for the treatment of refractory Behçet's disease: a case series

Recommendations related to ocular, mucosal and cutaneous involvement of Behçet's disease (BD) are mainly evidence-based, but in cases of vascular, neurological and gastrointestinal involvement there are no guidelines to define the best treatment strategy. We report three adult patients with BD, who received an interleukin-1β inhibitor by subcutaneous injections, canakinumab (at the dosage of 150 mg every 6 weeks), after failure shown by corticosteroids and different combinations of immunosuppressant agents. The prompt and sustained clinical efficacy demonstrated by canakinumab as a monotherapy supports the opportunity of using this specific anti-interleukin-1β agent as a valid therapeutic option for resistant or refractory BD. Open trials and observational studies should be performed to test canakinumab efficacy on a larger number of patients. The most appropriate dosage and intervals between administrations should be decided according to the individual patient, severity or recurrence of clinical manifestations and major organ involvement.