Autoinflammatory syndromes

NLRP3 gene variants and serum NLRP3 levels in periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome

OBJECTIVES

Although most of the autoinfammatory disorders have a confirmed genetic cause, periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome still has an unknown genetic background. However, familial cases of PFAPA syndrome have been reported suggesting a genetic its basis. PFAPA syndrome may also be considered an infammasome disorder as variants in infammasome-associated genes such as CARD8, NLRP3, and MEFV have been reported to contribute to the disease.

METHODS

Polymerase chain reaction (PCR)/Sanger sequencing analysis was performed for the detection of the variations in 71 PFAPA patients and 71 healthy controls. NLRP3 concentrations in serum were measured in 71 PFAPA patients and 71 healthy controls.

RESULTS

No statistically significant differences were observed in the allele or genotype frequencies of the NLRP3 polymorphisms between the controls and patients (P > 0.05). We found no significant differences for NLRP3 serum levels between PFAPA patients and controls (p > 0.05). Mutations in the MEFV gene were detected in 32.5% of our patients (13/40).

CONCLUSIONS

It seems that the synergistic effect of different genes plays a role in the formation of PFAPA syndrome. For this reason, it may be useful to examine the presence of mutations in genes such as NLRP3, MEFV, and CARD8 together while investigating the genetics of PFAPA syndrome. Key points • Familial cases of PFAPA syndrome have been reported suggesting a genetic basis for this syndrome. • Elevated serum or plasma levels of IL-1β, IL-6, and IL-18 have been demonstrated during PFAPA flares in several studies. • It seems that the synergistic effect of different genes plays a role in the formation of PFAPA syndrome.

Biomarkers and their Clinical Applications in Pediatrics

Biomarker studies are becoming increasingly interesting for many fields of medicine. The use of biomarkers in medicine is involved in detecting diseases and supporting diagnosis and treatment decisions. New research and new discoveries on the molecular basis of the disease show that there may be a number of promising new biomarkers for use in daily clinical practice. Clinical trials in children lag behind adult research both in quality and quantity. The number of biomarkers validated to optimize pediatric patient management is limited. In the pathogenesis of many diseases, it should not be extrapolated to the pediatric clinical setting, taking into account that biomarkers that are effective in adults are clearly different in children and that ontogeny directly affects disease development and therapeutic response in children. The search for ideal biomarkers or markers that can make an early and definitive diagnosis in neonatal sepsis is still ongoing. The ideal biomarker for pediatric diseases should be costeffective, noninvasive, applicable to pediatric specific diseases, and its results should correspond to age-related physiological changes. Lactate, troponin and B-type natriuretic peptide are valuable biomarkers in the evaluation and management of critically ill children with cardiac disease. Tumor markers in children are biochemical substances used in the clinical treatment of pediatric tumors and to detect the presence of cancer (regression or progression). In this chapter, current and brief information about biomarkers and their clinical applications used in the diagnosis and monitoring of pediatric diseases is presented.;

Approach to Children with Hives

Urticaria (or hives) is a pruritic and erythematous skin rash. Angioedema commonly occurs with urticaria. The term "chronic urticaria" is used when hives are present for more than 6 weeks. Acute urticaria is common in children, whereas chronic urticaria is rare. Causes of urticaria can be identified in many cases of acute urticaria with a thorough medical history. Laboratory evaluation may be needed to confirm the etiology of acute urticaria. Chronic urticaria is often idiopathic. Clinicians should avoid universal allergy testing for food allergens or aeroallergens in chronic urticaria as it usually does not help in identifying the cause, can lead to false-positive results, and unnecessary avoidance of allergens or foods. Urticarial vasculitis should be considered for lesions that are painful, present for more than 48 hours, leave scars/hyperpigmentation, or present with systemic symptoms such as fever, weight loss, and arthritis. Skin biopsy should be considered for suspected urticarial vasculitis. [Pediatr Ann. 2021(5):e191-e197.].

Autoinflammatory syndromes

Autoinflammatory syndromes are a steadily growing group of inflammatory diseases caused by abnormal regulations of the innate immune system. The clinical presentation is multifaceted, but recurrent fever, skin involvement, joint inflammation and other systemic symptoms of inflammation are characteristic. In contrast to classic autoimmune diseases, autoantibodies or specific T cells are not involved in the pathogenesis. In fact, innate immunity plays the most important role in autoinflammation. While activation of the innate immune system is usually self-limiting in healthy individuals, mutations and dysregulation can lead to chronic and excessive activation of innate immune responses and to the development of autoinflammatory diseases.

Novel PLCG2 Mutation in a Patient With APLAID and Cutis Laxa

Background: The auto-inflammation and phospholipase Cγ2 (PLCγ2)-associated antibody deficiency and immune dysregulation (APLAID) syndrome is a rare primary immunodeficiency caused by a gain-of-function mutation S707Y in the PLCG2 gene previously described in two patients from one family. The APLAID patients presented with early-onset blistering skin lesions, posterior uveitis, inflammatory bowel disease (IBD) and recurrent sinopulmonary infections caused by a humoral defect, but lacked circulating autoantibodies and had no cold-induced urticaria, contrary to the patients with the related PLAID syndrome. Case: We describe a new APLAID patient who presented with vesiculopustular rash in the 1st weeks of life, followed by IBD, posterior uveitis, recurrent chest infections, interstitial pneumonitis, and also had sensorineural deafness and cutis laxa. Her disease has been refractory to most treatments, including IL1 blockers and a trial with ruxolitinib has been attempted. Results: In this patient, we found a unique de novo heterozygous missense L848P mutation in the PLCG2 gene, predicted to affect the PLCγ2 structure. Similarly to S707Y, the L848P mutation led to the increased basal and EGF-stimulated PLCγ2 activity in vitro. Whole blood assays showed reduced production of IFN-γ and IL-17 in response to polyclonal T-cell stimulation and reduced production of IL-10 and IL-1β after LPS stimulation. Reduced IL-1β levels and the lack of clinical response to treatment with IL-1 blockers argue against NLRP3 inflammasome hyperactivation being the main mechanism mediating the APLAID pathogenesis. Conclusion: Our findings indicate that L848P is novel a gain-of-function mutation that leads to PLCγ2 activation and suggest cutis laxa as a possible clinical manifestations of the APLAID syndrome.

Skin symptoms as diagnostic clue for autoinflammatory diseases

Autoinflammatory disorders are immune-mediated diseases with increased production of inflammatory cytokines and absence of detectable autoantibodies. They course with recurrent episodes of systemic inflammation and fever is the most common symptom. Cutaneous manifestations are prevalent and important to diagnosis and early treatment of the syndromes. The purpose of this review is to emphasize to dermatologists the skin symptoms present in these syndromes in order to provide their early diagnosis.

New frontiers in the treatment of systemic juvenile idiopathic arthritis

Systemic juvenile idiopathic arthritis (sJIA) and its most significant complication, macrophage activation syndrome (MAS), have traditionally been treated with steroids and non-steroidal anti-inflammatory medications. However, the introduction of biologic medications that inhibit specific cytokines, such interleukins 1 and 6, has changed the treatment paradigm for sJIA patients. In this review, we discuss the therapies currently used in the treatment of sJIA as well as novel targets and approaches under consideration, including mesenchymal stromal cell therapy and JAK inhibitors. We also discuss targeting cytokines that have been implicated in MAS, such as interferon gamma and interleukin 18.

Periodic fevers and autoinflammatory syndromes in childhood

Recurrent fever is a common presentation in paediatric practice and can be caused by a wide variety of diseases including autoinflammatory conditions. The innate immune system plays an essential role in the 'first line' response to infection through mediation of inflammatory responses. Inflammasomes are part of the regulatory process for this system and result in the production of the powerful pro-inflammatory cytokine interleukin-1B. Dysregulation of inflammasomes, and Interleukin 1 production, contributes to the pathogenesis of autoinflammatory diseases. This review focuses on described periodic fever syndromes (PFS) which are now collectively referred to as autoinflammatory syndromes. Conditions discussed include periodic fever aphthous stomatitis pharyngitis and cervical adenopathy, familial Mediterranean fever, tumour necrosis factor receptor-associated periodic syndromes, hyperimmunoglobulinaemia D and the cryopyrin-associated periodic syndromes. Presenting features, complications, diagnostic and treatment approaches for these conditions are discussed. Nonetheless, as most of these conditions are rare and may have significant long-term complications, it is recommended that they be managed in consultations with a physician experienced in managing PFS.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Anti-Inflammatory Effects of Modified Adenoviral Vectors for Gene Therapy: A View through Animal Models Tested

The central dogma of gene therapy relies on the application of novel therapeutic genes to treat or prevent diseases. The main types of vectors used for gene transfer are adenovirus, retrovirus, lentivirus, liposome, and adeno-associated virus vectors. Gene therapy has emerged as a promising alternative for the treatment of inflammatory diseases. The main targets are cytokines, co-stimulatory molecules, and different types of cells from hematological and mesenchymal sources. In this review, we focus on molecules with anti-inflammatory effects used for in vivo gene therapy mediated by adenoviral gene transfer in the treatment of immune-mediated inflammatory diseases, with particular emphasis on autoinflammatory and autoimmune diseases.

Practice parameter for the diagnosis and management of primary immunodeficiency

The American Academy of Allergy, Asthma & Immunology (AAAAI) and the American College of Allergy, Asthma & Immunology (ACAAI) have jointly accepted responsibility for establishing the "Practice parameter for the diagnosis and management of primary immunodeficiency." This is a complete and comprehensive document at the current time. The medical environment is a changing environment, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, the ACAAI, and the Joint Council of Allergy, Asthma & Immunology. These parameters are not designed for use by pharmaceutical companies in drug promotion.

Treatment advances in systemic juvenile idiopathic arthritis

Systemic juvenile idiopathic arthritis (JIA) is an autoinflammatory condition that is distinct from other forms of childhood arthritis. Recently, biologic agents that specifically inhibit the cytokines interleukin (IL)-1 and IL-6 have demonstrated remarkable clinical effectiveness and confirmed the importance of these cytokines in the disease process. Future studies are likely to optimize the care of children with systemic arthritis and further elucidate the disease pathogenesis.

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

Autoinflammatory diseases are comprehensively caused by aberrant production of proinflammatory cytokines and are revealed by cyclically and spontaneously occurring inflammatory events. Over the last decade, there has been a revolution in the understanding of periodic fever syndromes, cryopyrinopathies, and skin disorders with pyogenic, granulomatous, or dystrophic features, which have been recognized across different countries spanning from the Mediterranean basin to the Japanese archipelago. Many children and adults with autoinflammatory diseases continue to elude diagnosis, and the diagnostic delay of many years puts these patients at risk of long-term severe complications, such as amyloidosis. Any hint of suspicion of autoinflammatory disease thus needs to be highlighted in various medical specialties, and this review examines their frequencies around the world, trying to match them with geographic location, ethnic and genetic data, in an attempt to realize a geoepidemiologic map for most of these conditions.

Common presentations of pediatric rheumatologic diseases: a generalist's guide

PURPOSE OF REVIEW

To present a case-based approach of three common scenarios which often present to the primary care physician. The approach to these cases and the differential diagnosis are discussed for these common rheumatologic diseases.

RECENT FINDINGS

Numerous healthy children and adolescents are referred to pediatric rheumatologists for the evaluation of suspected rheumatologic diseases. Often, general rheumatologic laboratory tests are sent which are not necessarily specific to the clinical situation. There is a high false-positive rate associated with many of these tests and undue anxiety and referrals result from these. Directed laboratory studies based on history and exam findings are more prudent and useful in the evaluation of these children. Routine antinuclear antibody testing, for example, is not recommended without supportive symptoms or signs.

SUMMARY

A practical approach for primary care physicians is described for the evaluation of patients suspected of having some of the more common pediatric rheumatologic symptoms and diseases.

Clinical genetic testing of periodic fever syndromes

Periodic fever syndromes (PFSs) are a wide group of autoinflammatory diseases. Due to some clinical overlap between different PFSs, differential diagnosis can be a difficult challenge. Nowadays, there are no universally agreed recommendations for most PFSs, and near half of patients may remain without a genetic diagnosis even after performing multiple-gene analyses. Molecular analysis of periodic fevers' causative genes can improve patient quality of life by providing early and accurate diagnosis and allowing the administration of appropriate treatment. In this paper we focus our discussion on effective usefulness of genetic diagnosis of PFSs. The aim of this paper is to establish how much can the diagnostic system improve, in order to increase the success of PFS diagnosis. The mayor expectation in the near future will be addressed to the so-called next generation sequencing approach. Although the application of bioinformatics to high-throughput genetic analysis could allow the identification of complex genotypes, the complexity of this definition will hardly result in a clear contribution for the physician. In our opinion, however, to obtain the best from this new development a rule should always be kept well in mind: use genetics only to answer specific clinical questions.