Monogenic Autoinflammatory Disorders Research Articles

Panniculitis: A Cardinal Sign of Autoinflammation.

Panniculitis was first described in the nineteenth century and is characterized by inflammation of the subcutaneous fat. It may be categorized in septal or lobular subtypes, but other histopathological features (e.g., presence of vasculitis, nature of inflammatory infiltrates, characteristics of fat necrosis) are also important for diagnostic purposes. Clinically, panniculitis is characterized by the presence of subcutaneous nodules, and both ulcerative and nonulcerative clinical subtypes have been proposed. In this review, we aimed to describe the occurrence of panniculitis in autoinflammatory disorders (AIDs) and related diseases. Among monogenic AIDs, panniculitis is common in IFN-mediated disorders. Panniculitis is a distinctive feature in proteasome-associated autoinflammatory syndromes (PRAAS), including chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) syndrome and Nakajo-Nishimura syndrome. On the other hand, erythema nodosum corresponds to the most common clinical form of panniculitis and is common in polygenic AIDs, such as Behçet's syndrome, inflammatory bowel disease, and sarcoidosis. Cytophagic histiocytic panniculitis, lipoatrophic panniculitis of children, and otulipenia are rare disorders that may also present with inflammation of the subcutaneous fat. Therefore, panniculitis can identify a specific subgroup of patients with AIDs and may potentially be regarded as a cardinal sign of autoinflammation.

The contributions of deleterious rare alleles in NLRP12 and inflammasome-related genes to polymyalgia rheumatica

Polymyalgia rheumatica (PMR) is a chronic inflammatory disease characterized by arthralgia and myalgia of the shoulder and hip girdles, and fever. PMR is linked to autoimmune diseases and autoinflammatory disorders. Exome sequencing has revealed the roles of rare variants in some diseases. Causative genes for monogenic autoinflammatory disorders might be candidate genes for the selective exome analysis of PMR. We investigated rare variants in the coding and boundary regions of candidate genes for PMR. Exome sequencing was performed to analyze deleterious rare variants in candidate genes, and the frequencies of the deleterious rare alleles in PMR were compared with those of Japanese population controls. Deleterious rare alleles in the NLRL12 gene were associated with PMR (P = 0.0069, Pc = 0.0415, odds ratio [OR] 4.49, 95% confidence interval [CI] 1.79–11.27). A multigene analysis demonstrated the deleterious rare allele frequency of the candidate genes for autoinflammatory disorders was also increased in PMR (P = 0.0016, OR 3.69, 95%CI 1.81–7.54). The deleterious rare allele frequencies of the candidate genes including NLRP12 were increased in PMR patients, showing links to autoinflammatory disorders in the pathogenesis of PMR.

Characterisation of IL-1 family members in Sweet syndrome highlights the overexpression of IL-1β and IL-1R3 as possible therapeutic targets.

Sweet syndrome (SS) as a prototypic neutrophilic dermatosis (NDs) shares certain clinical and histologic features with monogenic auto-inflammatory disorders in which interleukin (IL)-1 cytokine family members play an important role. This has led to the proposal that NDs are polygenic auto-inflammatory diseases and has fuelled research to further understand the role of IL-1 family members in the pathogenesis of NDs. The aim of this study was to characterise the expression of the IL-1 family members IL-1β, IL-36γ, IL-33 and IL-1R3 (IL-1RaP) in SS. The expression profile of IL-1β, IL-33, IL-36γ and their common co-receptor IL-1R3 was analysed by immunohistochemistry, in situ hybridisation and double immunofluorescence (IF) in healthy control skin (HC) and lesional skin samples of SS. Marked overexpression of IL-1β in the dermis of SS (p < 0.001), and a non-significant increase in dermal (p = 0.087) and epidermal (p = 0.345) IL-36γ expression compared to HC was observed. Significantly increased IL-1R3 expression within the dermal infiltrate of SS skin samples (p = 0.02) was also observed, whereas no difference in IL-33 expression was found between SS and HC (p = 0.7139). In situ hybridisation revealed a good correlation between gene expression levels and the above protein expression levels. Double IF identifies neutrophils and macrophages as the predominant sources of IL-1β. This study shows that IL-1β produced by macrophages and neutrophils and IL-1R3 are significantly overexpressed in SS, thereby indicating a potential pathogenic role for this cytokine and receptor in SS.

CPC14 A truly VEXing diagnosis

Abstract A 50-year-old man with a background of prostate cancer was admitted with fever, weight loss, polyarthritis, symptomatic anaemia and raised inflammatory markers. Multiple tender indurated violaceous plaques on the trunk and limbs were suggestive of Sweet syndrome. Skin biopsies revealed a neutrophilic dermal infiltrate and a pandermal vasculitis affecting small vessels. Laboratory screening (including rheumatoid factor, anticyclic citrullinated peptide, antinuclear antibody, antineutrophil cytoplasm antibodies, HIV, hepatitis B and C serology, antiphospholipid antibodies and cryoglobulins) was negative. Upper and lower endoscopies and gastrointestinal biopsies were normal. Biopsy of an axillary lymph node revealed reactive changes only. Computed tomography (CT) of the thorax, abdomen and pelvis showed sacroiliitis. A diffuse low signal on T1-weighted magnetic resonance imaging of his spine was suggestive of conversion of fatty marrow to red marrow. His cutaneous findings resolved fully with oral prednisolone 0.5 mg kg−1; however, he had ongoing transfusion-dependent anaemia and arthritis. Infliximab was started for presumed ankylosing spondylitis by rheumatology without improvement. Six months later, he was readmitted with multifocal ulceration of both feet. Histology demonstrated a leucocytoclastic vasculitis. He developed haemoptysis and chest pain. CT of the thorax showed multifocal, bilateral, ground–glass change consistent with pulmonary vasculitis. Bone marrow biopsy revealed hypercellular marrow with markedly increased granulopoiesis. A pathogenic missense mutation in UBA1 (c121A.G; pMet41Val) was found on next-generation sequencing of the bone marrow aspirate (Leeds Cancer Centre). Somatic variants at this codon have been implicated in vacuoles, E1 enzyme, X-linked, autoinflammatory and somatic (VEXAS) syndrome (Beck DB, Ferrada MA, Sikora KA et al. Somatic mutations in UBA1 and severe adult-onset autoinflammatory disease. N Engl J Med 2020; 383:2628–38). First described in 2020, VEXAS syndrome is a somatic monogenic autoinflammatory disorder of adulthood. Affected patients develop predominantly inflammatory and haematological symptoms. Cutaneous findings have been reported in up to 89% of cases (Georgin-Lavialle S, Terrier B, Guedon AF et al. Further characterization of clinical and laboratory features in VEXAS syndrome: large-scale analysis of a multicentre case series of 116 French patients. Br J Dermatol 2022; 186:564–74) and include neutrophilic dermatosis, vasculitis, urticaria, angioedema, erythematous papules and chondritis. Systemic manifestations are protean, but fever of noninfectious origin, weight loss, and ocular and pulmonary manifestations are most prevalent. Fifty per cent of patients with VEXAS have myelodysplastic syndrome (Georgin-Lavialle et al.). In our case, persistent haematological abnormalities coupled with multisystem inflammation (arthritis, vasculitis) prompted testing for VEXAS syndrome. This novel condition should be considered when assessing adult patients with neutrophilic dermatosis or cutaneous vasculitis who manifest other autoinflammatory phenomena. He was commenced on tocilizumab but, despite this, has ongoing acral vasculopathy.

B-cell driven autoimmunity in two patients with monogenic autoinflammatory disorders

RationaleAutoimmunity and autoinflammation are classically recognized as two different disease processes. In this report, we present two patients with Behcet’s disease (BD)-like autoinflammation who subsequently developed lupus-like serology and B-cell phenotypes. MethodA retrospective review of medical records and research-based flow cytometry of two patients with the monogenetic autoinflammatory disease was performed. ResultsOur first patient had a history of multiple skin and genital lesions, as well as persistent cough with pulmonary nodules. Her immune evaluation demonstrated marked CD4 activation with decreased naïve CD4 cells. Throughout her disease course, she developed high titer ANA and dsDNA. Her genetic analysis revealed a heterozygous c.1039C>T (p. Gln347*) variant of the RELA gene, a truncation mutation. The downstream truncated variant of the RELA gene has been reported to be associated with BD-like autoinflammatory syndrome. Our second patient had a BD-like presentation with recurrent mouth and vaginal ulcers, Crohn’s disease-like GI inflammation, and periodic fevers. She also had features of autoimmune disease with Hashimoto thyroiditis. At disease onset, she was negative for ANA. However, over a period of eight years, her ANA titers increased to >1:2560, with high titer anti-chromatin antibody and new-onset bilateral sacroiliitis. Her genetic testing revealed a (p.Arg364Lysfs*25) variant of the TNFAIP3 gene associated with BD-like autoinflammatory syndrome. Research-based B-cell profiles in both patients revealed increased B-cell autoreactivity and B-cell dysregulation similar to classical lupus patients. ConclusionOur case report demonstrated that the monogenetic autoinflammatory disease process could evolve to develop autoimmunity, thus complicating clinical presentation and management.

Cohort-driven variant burden analysis and pathogenicity identification in monogenic autoinflammatory disorders

Nearly 50 pathogenic genes and hundreds of pathogenic variants have been identified in monogenic autoinflammatory diseases (AIDs). Nonetheless, there are still many genes for which the pathogenic mechanisms are poorly understood, and the pathogenicity of many candidate variants needs to be determined. Monogenic AIDs are a group of rare genetic diseases characterized by inflammation as the phenotype. With the development of next-generation sequencing, pathogenic genes have been widely reported and used for clinical screening and diagnosis. The International Society for Systemic Autoinflammatory Diseases has recognized approximately 50 pathogenic genes and hundreds of related pathogenic variants in monogenic AIDs. We plan to investigate these pathogenic variants by conducting a variant burden analysis to determine whether or not there are consistent characteristics. We performed a variant burden analysis on the Genome Aggregation Database cohort using the currently reported genetic variants in monogenic AIDs, analyzing the enrichment of allelic signatures and deleterious predictions at the variants. Allelic signatures were extracted from Genome Aggregation Database, and the deleterious predictions were extracted from existing tools. The features obtained from the variant burden analysis were applied to the Random Forest model to classify the pathogenicity of novel mutations. Functional enrichment and network analysis of AID pathogenic genes have hinted at the possible involvement of unsuspected signals. The variant burden analysis demonstrated that the pathogenicity of a variant could not be reliably classified using only its allele frequency and deleterious predictions. However, variants of varying classifications of pathogenicity exhibited strikingly different patterns of the allelic signature in the upstream and downstream regions surrounding the variants. Furthermore, the distribution of deleterious variants surrounding the variants in the cohort varied significantly across pathogenicity categories. Finally, the cohort-based features extracted from the alleles were applied to the prediction of pathogenicity in monogenic AIDs, achieving superior prediction performance compared with other tools. The cohort-based features have potential applications across a more extensive variety of disease categories. The pathogenicity of a variant can be effectively classified on the basis of variant frequency and deleterious prediction of the allele in the cohort, and this information can be used to improve the accuracy of the current classification of the pathogenicity of the variant.

Mutations in the B30.2 and the central helical scaffold domains of pyrin differentially affect inflammasome activation

Familial Mediterranean Fever (FMF) is the most common monogenic autoinflammatory disorder. FMF is caused by mutations in the MEFV gene, encoding pyrin, an inflammasome sensor. The best characterized pathogenic mutations associated with FMF cluster in exon 10. Yet, mutations have been described along the whole MEFV coding sequence. Exon 10 encodes the B30.2 domain of the pyrin protein, but the function of this human-specific domain remains unclear. Pyrin is an inflammasome sensor detecting RhoA GTPase inhibition following exposure to bacterial toxins such as TcdA. Here, we demonstrate that the B30.2 domain is dispensable for pyrin inflammasome activation in response to this toxin. Deletion of the B30.2 domain mimics the most typical FMF-associated mutation and confers spontaneous inflammasome activation in response to pyrin dephosphorylation. Our results indicate that the B30.2 domain is a negative regulator of the pyrin inflammasome that acts independently from and downstream of pyrin dephosphorylation. In addition, we identify the central helical scaffold (CHS) domain of pyrin, which lies immediately upstream of the B30.2 domain as a second regulatory domain. Mutations affecting the CHS domain mimic pathogenic mutations in the B30.2 domain and render the pyrin inflammasome activation under the sole control of the dephosphorylation. In addition, specific mutations in the CHS domain strongly increase the cell susceptibility to steroid catabolites, recently described to activate pyrin, in both a cell line model and in monocytes from genotype-selected FMF patients. Taken together, our work reveals the existence of two distinct regulatory regions at the C-terminus of the pyrin protein, that act in a distinct manner to regulate positively or negatively inflammasome activation. Furthermore, our results indicate that different mutations in pyrin regulatory domains have different functional impacts on the pyrin inflammasome which could contribute to the diversity of pyrin-associated autoinflammatory diseases.

Central nervous system manifestations of monogenic autoinflammatory disorders and the neurotropic features of SARS-CoV-2: Drawing the parallels.

Central nervous system (CNS) involvement in monogenic autoinflammatory disorders (AID) is increasingly recognized and can be life threatening. Therefore, a low threshold to consider CNS disease should be maintained in patients with systemic inflammation. Hyperinflammation is also a key feature of severe acute COVID-19 and post COVID-19 entities such as multisystem inflammatory syndrome in children. Like AID, COVID-19 patients can present with severe CNS involvement. The impact of COVID-19 on AID and CNS involvement in particular is still obscure, nevertheless dreaded. In the current review, we synthesize the spectrum of CNS manifestations in monogenic AID. We explore common pathophysiological and clinical features of AID and COVID-19. Moreover, we assess the impact of immune dysregulation associated with SARS-CoV-2 infections and post COVID-19 hyperinflammation in AID. The striking commonalities found between both disease entities warrant caution in the management of AID patients during the current pandemic.

Adenosine Deaminase 2 Deficiency (DADA2): A Crosstalk Between Innate and Adaptive Immunity.

Deficiency of Adenosine deaminase 2 (DADA2) is a monogenic autoinflammatory disorder presenting with a broad spectrum of clinical manifestations, including immunodeficiency, vasculopathy and hematologic disease. Biallelic mutations in ADA2 gene have been associated with a decreased ADA2 activity, leading to reduction in deamination of adenosine and deoxyadenosine into inosine and deoxyinosine and subsequent accumulation of extracellular adenosine. In the early reports, the pivotal role of innate immunity in DADA2 pathogenic mechanism has been underlined, showing a skewed polarization from the M2 macrophage subtype to the proinflammatory M1 subtype, with an increased production of inflammatory cytokines such as TNF-α. Subsequently, a dysregulation of NETosis, triggered by the excess of extracellular Adenosine, has been implicated in the pathogenesis of DADA2. In the last few years, evidence is piling up that adaptive immunity is profoundly altered in DADA2 patients, encompassing both T and B branches, with a disrupted homeostasis in T-cell subsets and a B-cell skewing defect. Type I/type II IFN pathway upregulation has been proposed as a possible core signature in DADA2 T cells and monocytes but also an increased IFN-β secretion directly from endothelial cells has been described. So far, a unifying clear pathophysiological explanation for the coexistence of systemic inflammation, immunedysregulation and hematological defects is lacking. In this review, we will explore thoroughly the latest understanding regarding DADA2 pathophysiological process, with a particular focus on dysregulation of both innate and adaptive immunity and their interacting role in the development of the disease.

P158 A case of refractory paediatric Cogan’s syndrome treated with tocilizumab

Background/AimsCogan’s syndrome is a rare vasculitis, characterised by progressive sensorineural bilateral hearing loss, vestibular symptoms and non-syphilitic interstitial keratitis. We present a paediatric case which was refractory to initial treatment and subsequently successfully treated with Tocilizumab.MethodsCase report.ResultsA previously well 14-year-old boy presented with sudden onset hearing loss, tinnitus and vertigo. There was no history of new medication, trauma or tick bite. There was no family history of autoimmune disease or genetic hearing losses. On examination his cranial nerves except for vestibulocochlear were grossly intact. He had a steady gait with no cerebellar signs. Otoscopy was unremarkable. Audiology showed a moderate to severe sensorineural hearing loss bilaterally, worse on the right. He had normal type A tympanograms. An autoimmune screen was carried out which showed normal FBC, inflammatory markers, ACE and Chitotriosidase. ANCA, Rheumatoid factor and lyme serology were negative. MRI of the internal auditory meati was normal. He subsequently developed visual disturbance and was diagnosed with bilateral interstitial keratitis. A unifying diagnosis of Cogan’s syndrome was made. An MRI scan of his head, neck and upper thorax looking for evidence of large vessel vasculitis was normal. Genetics looking for evidence of a monogenic autoinflammatory disorder and primary immunodeficiency were negative. He was initially treated with a weaning course of oral prednisolone with improvement in symptoms. Unfortunately, 4 months later had clinical and audiological deterioration in hearing. He therefore received pulsed IV methylprednisolone and commenced subcutaneous methotrexate and adalimumab. 3 months later, there was both clinical and audiological improvement and he started to wean prednisolone. 7 months later, he presented with a 24-hour history of reduced hearing on the right, confirmed on audiogram. He received a further pulse of IV methylprednisolone and a short course of high-dose oral prednisolone, followed by a slowly weaning course. 3 months later, again he felt his hearing had deteriorated and this was confirmed on audiogram, with a 40-decibel loss in his previously good ear. He received two doses of IV methylprednisolone and background steroids were increased to 20mg daily. Due to frequent relapses, adalimumab was changed to IV tocilizumab at 10mg/kg 2-weekly, alongside methotrexate. IV tocilizumab was changed to the subcutaneous route during the COVID-19 pandemic and was tolerated well. His hearing subsequently improved and tocilizumab interval was extended to 3-weekly in Feb 2021. At last review he was stable and successfully transitioned to adult services.ConclusionEvidence regarding treatment options in paediatric patients is lacking due to the rarity of the condition and consequent difficulty in arranging high-quality trials. This is the first case report of use of tocilizumab for Cogan’s syndrome in children, highlighting it as a well-tolerated and successful treatment modality.Disclosure C. Anderson: None. K. McAllister: None. J. Walsh: None.

Clinical and molecular evaluation of MEFV gene variants in the Turkish population: a study by the National Genetics Consortium.

Familial Mediterranean fever (FMF) is a monogenic autoinflammatory disorder with recurrent fever, abdominal pain, serositis, articular manifestations, erysipelas-like erythema, and renal complications as its main features. Caused by the mutations in the MEditerranean FeVer (MEFV) gene, it mainly affects people of Mediterranean descent with a higher incidence in the Turkish, Jewish, Arabic, and Armenian populations. As our understanding of FMF improves, it becomes clearer that we are facing with a more complex picture of FMF with respect to its pathogenesis, penetrance, variant type (gain-of-function vs. loss-of-function), and inheritance. In this study, MEFV gene analysis results and clinical findings of 27,504 patients from 35 universities and institutions in Turkey and Northern Cyprus are combined in an effort to provide a better insight into the genotype-phenotype correlation and how a specific variant contributes to certain clinical findings in FMF patients. Our results may help better understand this complex disease and how the genotype may sometimes contribute to phenotype. Unlike many studies in the literature, our study investigated a broader symptomatic spectrum and the relationship between the genotype and phenotype data. In this sense, we aimed to guide all clinicians and academicians who work in this field to better establish a comprehensive data set for the patients. One of the biggest messages of our study is that lack of uniformity in some clinical and demographic data of participants may become an obstacle in approaching FMF patients and understanding this complex disease.

Early-onset pulmonary and cutaneous vasculitis driven by constitutively active SRC-family kinase HCK

Inborn errors of immunity are genetic disorders characterized by various degrees of immune dysregulation that can manifest as immune deficiency, autoimmunity, or autoinflammation. The routine use of next-generation sequencing in the clinic has facilitated the identification of an ever-increasing number of inborn errors of immunity, revealing the roles of immunologically important genes in human pathologies. However, despite this progress, treatment is still extremely challenging. We sought to report a new monogenic autoinflammatory disorder caused by a de novo activating mutation, p.Tyr515∗, in hematopoietic cell kinase (HCK). The disease is characterized by cutaneous vasculitis and chronic pulmonary inflammation that progresses to fibrosis. Whole-exome sequencing, Sanger sequencing, mass spectrometry, and western blotting were performed to identify and characterize the pathogenic HCK mutation. Dysregulation of mutant HCK was confirmed exvivo in primary cells and invitro in transduced cell lines. Mutant HCK lacking the C-terminal inhibitory tyrosine Tyr522 exhibited increased kinase activity and enhanced myeloid cell priming, migration and effector functions, such as production of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α, and production of reactive oxygen species. These aberrant functions were reflected by inflammatory leukocyte infiltration of the lungs and skin. Moreover, an overview of the clinical course of the disease, including therapies, provides evidence for the therapeutic efficacy of the Janus kinase 1/2 inhibitor ruxolitinib in inflammatory lung disease. We propose HCK-driven pulmonary and cutaneous vasculitis as a novel autoinflammatory disorder of inborn errors of immunity.

Regulation of cGAS-STING Pathway - Implications for Systemic Lupus Erythematosus.

Type I interferon (IFN-I) is implicated in the pathogenesis of systemic lupus erythematosus (SLE) and the closely associated monogenic autoinflammatory disorders termed the "interferonopathies." Recently, the cytosolic DNA sensor cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) and its downstream signaling adaptor stimulator of interferon genes (STING) have been identified as having important, if not central, roles in driving IFN-I expression in response to self-DNA. This review highlights the many ways in which this pathway is regulated in order to prevent self-DNA recognition and underlines the importance of maintaining tight control in order to prevent autoimmune disease. We will discuss the murine and human studies that have implicated the cGAS-STING pathway as being an important contributor to breakdown in tolerance in SLE and highlight the potential therapeutic application of this knowledge for the treatment of SLE.

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

To investigate survival of 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. Multicentre retrospective study analysing patients affected by the most common mAID treated with anakinra or canakinumab. Survival curves were analysed with the Kaplan-Meier method. Statistical analysis included a Cox-proportional hazard model to detect factors responsible for drug discontinuation. 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 [hazard ratio (HR) 2.573 (CI: 1.223, 5.411), P=0.013] on regression analysis. A significant glucorticoid-sparing effect was observed (P<0.0001). 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 favourable safety profile, which 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.

Efficacy and Safety of Janus Kinase Inhibitors in Type I Interferon-Mediated Monogenic Autoinflammatory Disorders: A Scoping Review

ImportanceType I interferon (IFN)-mediated monogenic autoinflammatory disorders (interferonopathies) are childhood-onset rare multisystemic diseases with limited treatment options. The Janus kinase (JAK) inhibitors are promising potential therapeutic candidates for immune-mediated chronic inflammatory skin diseases.ObjectiveTo review the use of JAK inhibitors to improve decision-making when treating interferonopathies with cutaneous manifestations.Evidence ReviewThe MEDLINE, EMBASE, CINAHL, Scopus, and Web of Science databases were searched for studies that used JAK protein inhibitors to treat IFN-related monogenic diseases with cutaneous manifestations in humans. The search results are reported using the scoping review approach.FindingsSeventeen open-label studies assessing the efficacy of ruxolitinib, baricitinib, or tofacitinib reported variable responses in patients with chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) and related syndromes, stimulator of IFN genes [STING]-associated vasculopathy with onset in infancy (SAVI), familial chilblain lupus (FCh-L), gain-of-function mutations of STAT1 (GOF-STAT1), or Aicardi-Goutiéres syndrome. JAK inhibitors improved clinical and analytical parameters and decreased flare numbers, plasma inflammatory markers, and expression of IFN-stimulated genes. BK viremia and upper respiratory infections were the most frequent and severe adverse events. Significant heterogeneity in efficacy assessment methods and poor reporting of safety events were detected.Conclusions and RelevanceEvidence of the use of JAK inhibitors in patients with interpheronopathies is scarce and of low methodological quality. Future clinical trials should use validated scales and report drug safety in a more accurate way.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13555-021-00517-9.

Deficiency of Lipin2 Results in Enhanced NF-κB Signaling and Osteoclast Formation in RAW-D Murine Macrophages.

Lipin2 is a phosphatidate phosphatase that plays critical roles in fat homeostasis. Alterations in Lpin2, which encodes lipin2, cause the autoinflammatory bone disorder Majeed syndrome. Lipin2 limits lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. However, little is known about the precise molecular mechanisms underlying its anti-inflammatory function. In this study, we attempted to elucidate the molecular link between the loss of lipin2 function and autoinflammatory bone disorder. Using a Lpin2 knockout murine macrophage cell line, we showed that lipin2 deficiency enhances innate immune responses to LPS stimulation through excessive activation of the NF-κB signaling pathway, partly because of TAK1 signaling upregulation. Lipin2 depletion also enhanced RANKL-mediated osteoclastogenesis and osteoclastic resorption activity accompanied by NFATc1 dephosphorylation and increased nuclear accumulation. These results suggest that lipin2 suppresses the development of autoinflammatory bone disorder by fine-tuning proinflammatory responses and osteoclastogenesis in macrophages. Therefore, this study provides insights into the molecular pathogenesis of monogenic autoinflammatory bone disorders and presents a potential therapeutic intervention.

Association between familial Mediterranean fever and multiple sclerosis: A case series from the JIR cohort and systematic literature review

IntroductionFamilial Mediterranean fever (FMF) is the most frequent monogenic autoinflammatory disorder; and leads to the uncontrolled production of interleukin (IL)-1β. Multiple sclerosis (MS) is an inflammatory disease of the central nervous system; and its development seems to be partly correlated with IL-1β levels. It is hypothesized that FMF could be associated with MS. We aim to describe the features of patients displaying both diseases and to investigate the MEFV mutation rate in MS patients. MethodsPatients with definite MS were retrieved from the cohort of FMF patients in the Reference Center for Rare Auto-inflammatory Diseases and Amyloidosis (CEREMAIA). We also performed a systematic literature review of articles from PubMed that were published from 1990 to 2020. ResultsTwenty-four patients were included in the case series: five patients (1.3%) from our cohort of 364 and 19 patients from the literature. The sex ratio was 2:1. The mean age at diagnosis of FMF was 19 years old; and that for MS was 29 years old. Seven studies investigating the MEFV mutation rate in MS patients were included. Three studies found a higher mutation rate in MS patients than in the control group. ConclusionFMF and MS features were comparable to those of patients with unrelated diseases; and MEFV mutation carriage was not positively correlated with MS. However; MS prevalence in FMF patients was higher than was expected in a healthy population. To a lesser extent; FMF prevalence in MS patients was higher than expected in a healthy population and the difference might not be significant. These data suggest that FMF could be associated with MS; and further studies are needed to investigate a potential causal association.

Monogenic autoinflammatory disorders: Conceptual overview, phenotype, and clinical approach

Monogenic autoinflammatory disorders: Conceptual overview, phenotype, and clinical approach

Identification of a New Mutation (C.562G>T P. Gly188) in a Young Man Affected by NLRP12 Associated Periodic Syndrome (NAPS12): Efficacy of Anti-IL1-Beta Treatment

NLRP12 associated periodic syndrome, also called Familial Cold Autoinflammatory Syndrome-2 (FCAS2), is a monogenic autoinflammatory disorder caused by mutations of the gene NLRP12 and is characterized by recurrent episodes of fever, often after cold exposure or physical stress, in association with arthralgias/arthritis, myalgias, headaches, aphthous ulcers, lymphadenopathy, abdominal pain, sierositis, dermatitis and urticaria. The episodes can last several days and can be very disabling. In the latest years different mutations of NLRP12 have been identified, explaining the clinical heterogeneity and the different response to treatments. Here we describe a case of a 24-years-old man affected by FCAS2 with a new nonsense mutation of the gene NLRP12 who initially had a good response to steroid therapy and subsequently to anti-IL-1 beta treatment.

Monogenic autoinflammatory disorders: beyond the periodic fever.

The past two decades have seen an exponential increase in the number of monogenic autoinflammatory disorders described, coinciding with improved genetic sequencing techniques. This group of disorders has evolved to be heterogeneous and certainly more complex than the original four 'periodic fever syndromes' caused by innate immune over-activation. This review aims to provide an update on the classic periodic fever syndromes as well as introducing the broadening spectrum of clinical features seen in more recently described conditions.