Systematic literature review of efficacy/effectiveness and safety of current therapies for the treatment of cryopyrin-associated periodic syndrome, hyperimmunoglobulin D syndrome and tumour necrosis factor receptor-associated periodic syndrome

Long-Term Safety and Effectiveness of Canakinumab in Patients with MKD/HIDS: Interim Analysis of the RELIANCE Registry

INTRODUCTION

Interim analysis of the long-term safety and effectiveness of canakinumab, at a patient level, in the mevalonate kinase deficiency/hyperimmunoglobulin-D syndrome (MKD/HIDS) cohort of the RELIANCE registry.

METHODS

From June 2018, the RELIANCE registry enrolled paediatric (aged ≥ 2 years) and adult patients (aged ≥ 18 years) with MKD/HIDS who were receiving canakinumab as part of their routine medical care. Safety, physician- and patient-reported measures of disease activity and dosing patterns were evaluated at baseline and every 6 months until end-of-study visit.

RESULTS

At the analysis cut-off date of December 2022, eight patients with MKD/HIDS were enrolled. Five (62.5%) were children (< 18 years) and five (62.5%) were female. The median patient age was 8.0 (range 2.0-39.0) years, and all patients were pre-treated with canakinumab prior to enrolment (median duration of canakinumab treatment: 3.8 years). Canakinumab was well tolerated, with seven (87.5%) patients reporting 48 adverse events (incidence rate/100 patient years: 218.1). No serious adverse drug reactions were reported. Patients continued to receive vaccinations during long-term treatment with canakinumab. Disease activity, evaluated by physician-reported (physician's global assessment, disease remission, C-reactive protein, serum amyloid A, erythrocyte sedimentation rate) and patient-reported (autoinflammatory disease activity index diary, disease activity, fatigue, impact on social life) measures, was generally well controlled throughout the study. Over 50.0% of patients maintained disease remission from baseline to month 24, and medians of all inflammatory markers remained within normal limits throughout the study. Most patients received higher than the recommended starting dose of canakinumab throughout the study.

CONCLUSION

Data from this interim analysis of a unique registry of patients with a rare disease support the long-term safety and effectiveness of the IL-1-blocking agent canakinumab for the treatment of MKD/HIDS.

Tocilizumab effectively reduces flares of hyperimmunoglobulin D syndrome in children: Three cases in China

Hyperimmunoglobulin D syndrome (HIDS) is a rare but severe autoinflammatory disease with a poor prognosis if not diagnosed and treated early. Here, we report three cases of HIDS in children with typical clinical manifestations and a clear genetic diagnosis. Patient 1 experienced recurrent fever flares with a maculo-papular skin rash. Patient 2 presented with periodic fever, cholestasis, lymphadenopathy, aphthous stomatitis, arthralgia, and abdominal pain and underwent surgery for intestinal obstruction. Patient 3, a sibling of patient 2, presented with periodic fever and underwent a surgical procedure for intussusception. All three patients were administered interleukin (IL)-6 receptor antagonist (tocilizumab). The results showed that tocilizumab effectively reduced inflammatory flares. Early diagnosis and tocilizumab treatment are effective at improving the prognosis of HIDS patients.

A rare missense p.C125Y mutation in the TNFRSF1A gene identified in a Chinese family with tumor necrosis factor receptor-associated periodic fever syndrome

Background

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is a rare autosomal dominant disorder with a low incidence in Asia. The most frequent clinical manifestations include fever, rash, myalgia, joint pain and abdominal pain. Misdiagnosis rates are high because of the clinical and genetic variability of the disease. The pathogenesis of TRAPS is complex and yet to be fully defined. Early genetic diagnosis is the key to precise treatment.

Methods

In this study, a Chinese family with suspected TRAPS were analyzed by genome-wide SNP genotyping, linkage analysis and targeted sequencing for identification of mutations in causative genes. To study the pathogenicity of the identified gene mutation, we performed a conservation analysis of the mutation site and protein structure analysis. Flow cytometry was used to detect TNFRSF1A shedding and quantitative real-time PCR were used to assess the activation of unfolded protein response (UPR) in the mutation carriers and healthy individuals.

Results

A typical TRAPS family history, with a pattern of autosomal dominant inheritance, led to the identification of a rare mutation in the TNFRSF1A gene (c.G374A [p.Cys125Tyr]) with unknown significance. The patient responded well to corticosteroids, and long-term therapy with colchicine effectively reduced the inflammatory attacks. No amyloid complications occurred during the 6-year follow-up. In silico protein analysis showed that the mutation site is highly conversed and the mutation prevents the formation of intrachain disulfide bonds in the protein. Despite a normal shedding of the TNFRSF1A protein from stimulated monocytes in the TRAPS patients with p.C125Y mutation, the expression of CHOP and the splicing of XBP1 was significantly higher than healthy controls, suggesting the presence of an activation UPR.

Conclusion

This is the first report of a Chinese family with the rare p.C125Y mutation in TNFRSF1A. The p.C125Y mutation does not result in aberrant receptor shedding, but instead is associated with an activated UPR in these TRAPS patients, which may provide new insights into the pathogenesis of this rare mutation in TRAPS.

Monitoring of Adverse Events and Safety in Autoinflammatory Diseases: Real-Life Data from the Eurofever Registry

OBJECTIVES

The study is aimed to evaluate the impact of safety events in the Eurofever registry for Autoinflammatory diseases.

METHODS

This was a retrospective and longitudinal observational multicentre study. Data were retrieved from the international registry Eurofever, starting patients' enrolment since 2009. All moderate, severe, or very severe AEs reported by treating physician in Eurofever were analyzed regardless of a possible suspected causal relationship to any therapies and according to the latest release of the Medical Dictionary for Regulatory Activities.

RESULTS

Complete information on safety were available in 2464 patients enrolled in the registry. In 1499 of them retrospective data encompassing the period from disease onset to enrolment were available, whereas 965 consecutive patients entered in the longitudinal part of the study. A total of 479 AEs have been reported in 275 patients. Eighty-two AEs were reported as serious and 99 were drug-related according to the physicians. Infections or infestations (94; 19.6%), gastrointestinal disorders (66; 13.8%), nervous system disorders (41; 8.6%) and systemic disorders or administration site reactions (35; 7.3%) were the most frequent reported events. The highest absolute number of drug-related AEs were related to biologic DMARDs (40/99 reports, 40,4%) and colchicine (31/99 reports, 31.3%).

CONCLUSIONS

Present study shows the importance of a longitudinal and homogeneous registration of the AEs in rare conditions, with a particular focus on the safety profile of the treatments used in these conditions.

Tocilizumab for treating mevalonate kinase deficiency and TNF receptor-associated periodic syndrome: a case series and literature review

BACKGROUND

Mevalonate kinase deficiency (MKD) and TNF receptor-associated periodic syndrome (TRAPS) are categorized as systemic autoinflammatory diseases (SAIDs), which are rare diseases characterized by early onset, severe conditions, and challenging diagnosis and treatment. Although different SAIDs have varying standard treatments, some SAIDs are poorly controlled after routine treatment, seriously affecting the growth and development of children and their quality of life. This study aims to provide more treatment strategies for SAIDs.

CASE PRESENTATION

We present two Chinese patients with MKD and TRAPS who were resistant to TNF- (tumor necrosis factor-) α blockade. After using etanercept, baricitinib, and glucocorticoid, patients with MKD and TRAPS still had periodic fever and rash. Due to the unavailability of IL-1 antagonists in the Chinese Mainland, we started administering intravenous tocilizumab (TCZ) at a dosage of 240 mg every three weeks. They had not experienced fever or rash after receiving one or two doses of TCZ. Before treatment with TCZ in the MKD patient, white blood cell (WBC) count, and TNF-α level were normal, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) increased significantly, and IL-6 increased slightly. After treatment with TCZ, ESR and CRP levels returned to normal; however, IL-6 increased occasionally. In the TRAPS patient, ESR, CRP, WBC, IL-6, and TNF-α levels were increased significantly. After TCZ treatment, ESR, CRP, WBC, IL-6, and TNF-α levels returned to normal. The two patients were treated with TCZ for more than six months and achieved clinical and serological remission. Furthermore, they had no adverse reactions after injection of TCZ.

CONCLUSION

In the absence of IL-1 antagonists in mainland China, tocilizumab emerges as an alternative drug in SAIDs that are resistant to TNF-α blockade.

Efficacy of Anakinra Treatment in two Moroccan Patients With Mevalonate Kinase Deficiency

Mevalonate kinase deficiency (MKD) is a rare hereditary autoinflammatory disease, with a widely variable clinical spectrum. It is characterized by febrile recurrent episodes and systemic inflammation. Data on therapeutic options for MKD are still limited and remain unknown in our country. We report Moroccan cases with MKD referred in our unit and treated with Anakinra, an interleukin-1 receptor antagonist. Through this study, we evaluate the efficacy of this bioagent, in our 2 MKD patients, in whom Anakinra has shown a complete clinical remission, with a remaining mild inflammation for one case, and normalization of growth with rare episodes of cervical adenopathies for the second case. Our experience provides an additional argument supporting the efficacy of Anakinra treatment, demonstrated previously but still lacks of objective data.

Dermatologic Manifestations of Noninflammasome-Mediated Autoinflammatory Diseases

Autoinflammatory diseases (AIDs) arise from disturbances that alter interactions of immune cells and tissues. They give rise to prominent (auto)inflammation in the absence of aberrant autoantibodies and/or autoreactive T cells. AIDs that are predominantly caused by changes in the inflammasome pathways, such as the NLRP3- or pyrin-associated inflammasome, have gained substantial attention over the last years. However, AIDs resulting primarily from other changes in the defense system of the innate immune system are less well-studied. These noninflammasome-mediated AIDs relate to, for example, disturbance in the TNF or IFN signaling pathways or aberrations in genes affecting the IL-1RA. The spectrum of clinical signs and symptoms of these conditions is vast. Thus, recognizing early cutaneous signs constitutes an important step in differential diagnoses for dermatologists and other physicians. This review provides an overview of the pathogenesis, clinical presentation, and available treatment options highlighting dermatologic aspects of noninflammasome-mediated AIDs.

Protective effect of anakinra on audiovestibular function in a murine model of endolymphatic hydrops

Introduction

Ménière's disease (MD), a common disease in the inner ear, is characterized by an increase in endolymph in the cochlear duct and vestibular labyrinth. The pathophysiology of the condition appears to be the immune response. Studies have shown that basal levels of the IL-1β increased in some MD patients.

Methods

Here, we used a murine model of endolymphatic hydrops (EH) to study the effect of anakinra on auditory and vestibular function. Mice were intraperitoneal injected with anakinra or saline before LPS by postauricular injection. Weight and disease severity were measured, histologic changes in auditory were assessed, and inflammation state was evaluated.

Results

We found that anakinra therapy reduced LPS-induced EH, alleviated LPS-induced hearing loss and vestibular dysfunction, and inhibited the expression of the inflammatory cytokines and macrophage infiltration in the cochlea of mice. We further demonstrated that anakinra ameliorated the disorganization and degeneration of myelin sheath, and reduced the neuron damage in cochlea of EH mice.

Discussion

Consequently, anakinra contributes to a promising therapeutic approach to MD, by restricting EH, alleviating auditory and vestibular function, inhibiting inflammation of the inner ear and protecting the cochlear nerve. Further investigations are needed to assess the potential therapeutic benefits of anakinra in patients with MD.

NLRP3 inflammasome and NLRP3-related autoinflammatory diseases: From cryopyrin function to targeted therapies

The NLRP3 inflammasome is one of the NOD-like receptor family members with the most functional characterization and acts as a key player in innate immune system, participating in several physiological processes including, among others, the modulation of the immune system response and the coordination of host defences. Activation of the inflammasome is a crucial signaling mechanism that promotes both an acute and a chronic inflammatory response, which can accelerate the production of pro-inflammatory cytokines, mainly Interleukin (IL)-1β and IL-18, leading to an exacerbated inflammatory network. Cryopyrin associated periodic syndrome (CAPS) is a rare inherited autoinflammatory disorder, clinically characterized by cutaneous and systemic, musculoskeletal, and central nervous system inflammation. Gain-of-function mutations in NLRP3 gene are causative of signs and inflammatory symptoms in CAPS patients, in which an abnormal activation of the NLRP3 inflammasome, resulting in an inappropriate release of IL-1β and gasdermin-D-dependent pyroptosis, has been demonstrated both in in vitro and in ex vivo studies. During recent years, two new hereditary NLRP3-related disorders have been described, deafness autosomal dominant 34 (DFN34) and keratitis fugax hereditaria (KFH), with an exclusive cochlear- and anterior eye- restricted autoinflammation, respectively, and caused by mutations in NLRP3 gene, thus expanding the clinical and genetic spectrum of NLRP3-associated autoinflammatory diseases. Several crucial mechanisms involved in the control of activation and regulation of the NLRP3 inflammasome have been identified and researchers took advantage of this to develop novel target therapies with a significant improvement of clinical signs and symptoms of NLRP3-associated diseases. This review provides a broad overview of NLRP3 inflammasome biology with particular emphasis on CAPS, whose clinical, genetic, and therapeutic aspects will be explored in depth. The latest evidence on two “new” diseases, DFN34 and KFH, caused by mutations in NLRP3 is also described.

The Preferential Use of Anakinra in Various Settings of FMF: A Review Applied to an Updated Treatment-Related Perspective of the Disease

Familial Mediterranean fever (FMF), the most frequent monogenic autoinflammatory disease, is manifested with recurrent and chronic inflammation and amyloid A (AA) amyloidosis, driven by overproduction of interleukin 1 (IL-1) through an activated pyrin inflammasome. Consequently, non-responsiveness to colchicine, the cornerstone of FMF treatment, is nowadays addressed by IL-1- blockers. Each of the two IL-1 blockers currently used in FMF, anakinra and canakinumab, has its own merits for FMF care. Here we focus on anakinra, a recombinant form of the naturally occurring IL-1 receptor antagonist, and explore the literature by using PubMed regarding the utility of anakinra in certain conditions of FMF. Occasionally we enrich published data with our own experience. To facilitate insights to anakinra role, the paper briefs some clinical, genetic, pathogenetic, and management aspects of FMF. The clinical settings of FMF covered in this review include colchicine resistance, AA amyloidosis, renal transplantation, protracted febrile myalgia, on- demand use, leg pain, arthritis, temporary suspension of colchicine, pediatric patients, and pregnancy and lactation. In many of these instances, either because of safety concerns or a necessity for only transient and short-term use, anakinra, due to its short half-life, is the preferred IL-1 blocker.

Chemical Modulation of Gasdermin-Mediated Pyroptosis and Therapeutic Potential

Pyroptosis, a lytic form of programmed cell death, both stimulates effective immune responses and causes tissue damage. Gasdermin (GSDM) proteins are a family of pore-forming executors of pyroptosis. While the most-studied member, GSDMD, exerts critical functions in inflammasome biology, emerging evidence demonstrates potential broad relevance for GSDM-mediated pyroptosis across diverse pathologies. In this review, we describe GSDM biology, outline conditions where inflammasomes and GSDM-mediated pyroptosis represent rational therapeutic targets, and delineate strategies to manipulate these central immunologic processes for the treatment of human disease.

The Role of Inflammasomes in the Pathogenesis of Neurodegenerative Diseases

Abstract—Protein misfolding and accumulation of protein aggregates is a distinctive feature of most neurodegenerative diseases. They lead to disruption of cellular homeostasis, loss of synaptic connections, and therefore cellular apoptosis. It has been demonstrated that some innate immune responses play an important role in the emergence and progression of neurodegenerative diseases. Inflammasomes are components of innate immunity that play a major role in the maintenance of chronic inflammation. Inflammasomes function as intracellular sensors, detecting both exogenous and endogenous stimuli. They also take part in caspase-1 activation and the synthesis of pro-inflammatory cytokines. In the central nervous system (CNS), inflammasomes are predominantly expressed by microglia, the key cells of innate immunity responsible for activation and maintenance of inflammation. In addition to microglia, inflammasomes can be expressed and activated by astrocytes and neurons, as well as infiltrating myeloid cells. Understanding the mechanisms of activation and functioning of inflammasomes is crucial for the development of novel drugs targeted at modulation of the immune response associated with their excessive activation. This review provides up-to-date information on the inflammasome structure and mechanisms of action, the role of protein misfolding, aggregation and the influence of these factors on inflammasome activation, as well as potential therapeutic targets in neurodegenerative diseases.

[What is confirmed in the treatment of autoinflammatory fever diseases?]

In den letzten 20 Jahren hat die Aufklärung von monogenetisch verursachten periodischen Fiebererkrankungen zum eigenständigen Konzept der Autoinflammation geführt. In diese heterogene Gruppe werden inzwischen auch polygenetisch verursachte, komplexe Erkrankungen eingruppiert. Das Spektrum der Krankheitsbilder wächst kontinuierlich. Hauptunterschied zur Autoimmunität ist eine übermäßige Aktivierung des angeborenen Immunsystems ohne Autoantikörperbildung oder antigenspezifische T‑Zellen. Als Kardinalsymptom treten rezidivierende Fieberschübe, begleitet von Entzündungszeichen, auf; diese wechseln sich bei den periodischen Krankheitsbildern mit Intervallen allgemeinen Wohlbefindens ab. Die klassischen monogenetischen Erkrankungen werden auch als hereditäres rezidivierendes Fieber (HRF) bezeichnet. Beispiele sind das familiäre Mittelmeerfieber (FMF), das Cryopyrin-assoziierte periodische Syndrom (CAPS), das Tumor-Nekrose-Faktor-Rezeptor-1-assoziierte periodische Syndrom (TRAPS), die Adenosindesaminase(ADA2)-Defizienz und die Mevalonatkinasedefizienz (MKD; Hyper-IgD-Syndrom). Die polygenetischen Erkrankungen werden auch als nichthereditäre Fiebersyndrome bezeichnet. Hierzu zählen die adulte Form der Still-Erkrankung („adult-onset Still’s disease“, AoSD), die Adamantiades-Behçet-Erkrankung, das PFAPA-Syndrom (periodisches Fieber, aphthöse Stomatitis, Pharyngitis und zervikale Adenitis) und die Gichtarthritis. Alle autoinflammatorischen Fiebersyndrome gehen mit einem von individuellem Schweregrad und Therapieerfolg abhängigen Langzeitrisiko für die Entwicklung einer Amyloid-A-Amyloidose einher. Bei einigen Erkrankungen können z. T. schwere Komplikationen auftreten.

Reasons for canakinumab initiation among patients with periodic fever syndromes: a retrospective medical chart review from the United States

BACKGROUND

Although canakinumab has demonstrated efficacy in multiple trials in patients with periodic fever syndromes (PFS), the evidence on initiation of canakinumab among PFS patients in real world setting is not well understood. We aimed to characterize the reasons for canakinumab initiation among patients with PFS, specifically, cryopyrin-associated periodic syndrome (CAPS), hyperimmunoglobulin D syndrome/mevalonate kinase deficiency (HIDS/MKD), TNF receptor-associated periodic syndrome (TRAPS) and familial Mediterranean fever (FMF).

METHODS

Physicians retrospectively reviewed the medical charts of PFS patients prescribed canakinumab between 2016 and 2018. Information collected included patient clinical characteristics, reasons for previous treatment discontinuation and canakinumab initiation. The results were summarized for overall patients, and by children (< 18 years) and adults and by subtype of PFS.

RESULTS

Fifty-eight physicians in the US (rheumatologists, 44.8 %; allergists/immunologists, 29.3 %; dermatologists, 25.9 %) abstracted information for 147 patients (children, 46.3 %; males, 57.1 %; CAPS, 36.7 %; TRAPS, 26.5 %; FMF, 26.5 %; HIDS/MKD, 6.8 %; Mixed, 3.4 %). Overall, most patients (90.5 %) received treatment directly preceding canakinumab (NSAIDs, 27.8 % [40.0 % in HIDS/MKD]; anakinra, 24.1 % [32.7 % in CAPS]; colchicine, 21.8 % [35.9 % in FMF]), which were discontinued due to lack of efficacy/effectiveness (39.5 %) and availability of a new treatment (36.1 %). The common reasons for canakinumab initiation were physician perceived efficacy/effectiveness (81.0 %; children, 75.0 %; adults, 86.1 %), lack of response to previous treatment (40.8 %; children, 38.2 %; adults, 43.0 %) and favorable safety profile/tolerability (40.1 %; children, 42.6 %; adults, 38.0 %). Within subtypes, efficacy/effectiveness was the most stated reason for canakinumab initiation in HIDS/MKD (90.9 %), lack of response to previous treatment in FMF (52.4 %) and convenience of administration/dosing in CAPS (27.1 %).

CONCLUSIONS

This study provided insights into how canakinumab is initiated in US clinical practice among PFS patients, with physician perceived efficacy/effectiveness of canakinumab, lack of response to previous treatment and favorable safety profile/tolerability of canakinumab being the dominant reasons for canakinumab initiation in all patients and in children and adults and PFS subtypes. Notably, the favorable safety profile/tolerability of canakinumab was more often the reason for initiation among children versus adults.

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.

Idiopathic recurrent pericarditis - a new orphan autoinflammatory disease? A retrospective analysis of cases of idiopathic recurrent pericarditis and a design of а double-blind, randomized, placebo-controlled study to evaluate the efficacy and safety of RPH-104 treatment in patients with idiopathic recurrent pericarditis

Aim To analyze cases of idiopathic recurrent pericarditis (IRP) in the structure of pericardial diseases of various origins from patient visits to the Multidisciplinary Federal Center.Material and methods A retrospective analysis of case records was performed for patients admitted to the V.A. Almazov National Medical Research Center from January 1, 2015 through January 1, 2020 for pericardial effusion of different etiologies.Results For the study period, 4 981 new cases of pericardial damage of different etiologies were found. Among these cases, postpericardiotomy syndrome accounted for 4 360 cases and pericarditis for 621 cases. IRP was detected in 34 cases, which amounted to 5.4 %. Based on the study data, the estimated IRP prevalence in the Russian Federation can be 1.1 cases per 100 thousand population.Conclusion IRP should be regarded as a new autoinflammatory disease, the prevalence of which borders on that of adult Still disease and should be addressed within the concept of orphan diseases. Current knowledge of the pathogenesis and data from recent studies demonstrated a great importance of interleukin-1 blockade as a leading mechanism for achieving remission. This has justified conduction of a randomized clinical study at the Center.

Identification of Critical Transcriptomic Signaling Pathways in Patients with H Syndrome and Rosai-Dorfman Disease

Biallelic mutations in SLC29A3 cause histiocytosis-lymphadenopathy plus syndrome, also known as H syndrome (HS). HS is a complex disorder, with ~ 25% of patients developing autoinflammatory complications consisting of unexplained fevers, persistently elevated inflammatory markers, and unusual lymphadenopathies, with infiltrating CD68⁺, S100⁺, and CD1a^- histiocytes, resembling the immunophenotype found in Rosai-Dorfman disease (RDD). We investigated the transcriptomic profiles of monocytes, non-activated (M0), classically activated (M1), and alternatively activated macrophages (M2) in two patients with HS, one without autoinflammatory (HS1) and one with autoinflammatory complications (HS2). RNA sequencing revealed a dysregulated transcriptomic profile in both HS patients compared to healthy controls (HC). HS2, when compared to HS1, had several differentially expressed genes, including genes associated with lymphocytic-histiocytic predominance (e.g. NINL) and chronic immune activation (e.g. B2M). The transcriptomic and cytokine profiles of HS patients were comparable to patients with SAID with high levels of TNF. SERPINA1 gene expression was found to be upregulated in all patients studied. Moreover, higher levels of IFNγ were found in the serum of both HS patients when compared to HC. Gene ontology (GO) enrichment analysis of the DEGs in HS patients revealed the terms "type I IFN," "IFNγ signaling pathway," and "immune responses" as the top 3 most significant terms for monocytes. Gene expression analysis of lymph node biopsies from sporadic and H syndrome-associated RDD suggests common underlying pathological process. In conclusion, monocytes and macrophages from both HS patients showed transcriptomic profiles similar to SAIDs and also uniquely upregulated IFNγ signature. These findings may help find better therapeutic options for this rare disorder.

Pediatric Inflammatory Multisystem Syndrome and Rheumatic Diseases During SARS-CoV-2 Pandemic

Globally, the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), appeared to have a milder clinical course in children compared to adults. As severe forms of COVID-19 in adults included an aberrant systemic immune response, children with chronic systemic inflammatory diseases were cautiously followed. No evidence for a specific susceptibility was identified in this pediatric population. European and US Pediatricians started to notice cases of myocarditis, sharing some features with toxic shock syndrome, Kawasaki disease, and macrophage activation syndrome in otherwise healthy patients. Multisystem Inflammatory Syndrome in Children (MIS-C) and Pediatric Inflammatory Multisystem Syndrome (PIMS) have designated this new entity in the US and Europe, respectively. The spectrum of severity ranged from standard hospitalization to pediatric intensive care unit management. Most patients had a clinical history of exposure to COVID-19 patients and/or SARS-COV2 biological diagnosis. Clinical presentations include fever, cardiac involvement, gastro-intestinal symptoms, mucocutaneous manifestations, hematological features, or other organ dysfunctions. The temporal association between the pandemic peaks and outbreaks of PIMS seems to be in favor of a post-infectious, immune-mediated mechanism. Thus, SARS-CoV2 can rarely be associated with severe systemic inflammatory manifestations in previously healthy children differently from adults highlighting the specific need for COVID-19 research in the pediatric population.