Mevalonate Kinase Research Articles

Fitness to Serve in the Armed Forces and Internal Medicine: A Retrospective Study.

Assessment of the medical fitness to serve in the armed forces has two objectives: to prevent the military operations from being jeopardized by a medical issue, and to protect soldiers from the sequelae of diseases that could become complicated in the operational field, especially in overseas operations where soldiers are exposed to a remote setting and a long evacuation time. Little is known about fitness decisions for soldiers with systemic or autoimmune diseases. Therefore, we conducted a single-center retrospective study of internal medicine fitness decisions. All the fitness decisions discussed from September 2019 to December 2020 in our department of internal medicine were reviewed. Gender, age, army or service, rank, garrison and health topic were collected from the medical files. Our Military Hospital local ethics committee, in accordance with the French law, approved this study. There were 41 cases, involving 31 men and 10 women (mean age: 31 years), presenting with autoimmune or systemic diseases, metabolic disorders, thrombophilia, congenital or acquired malformations or organ failure, miscellaneous nephropathies, or hemogram abnormalities. Four patients were taking immunosuppressive agents, 3 biologics, and 4 anticoagulants. Among the 15 civilians requiring medical fitness assessment to enlistment, 6 were declared fit. They presented with a history of juvenile idiopathic arthritis with intermediate uveitis without relapse for 7 years, Mayer-Rokitansky-Küster-Hauser syndrome type II with ectopic kidney, solitary kidney with normal renal function and with hypertension, isolated proteinuria, proteinuria with microscopic hematuria, and muscular fibrolipoma with a history of surgical treatment of a vascular malformation. Among the 26 patients already enlisted in the armed forces, 9 were referred for assessment of medical fitness to serve overseas. Two soldiers were assessed as fit without restrictions; one presented with a history of a single episode of deep vein thrombosis after surgery, and the other had a history of monoclonal gammopathy of renal significance without relapse and without treatment for 8 years. Four soldiers were assessed as fit only for overseas territories with sanitary structures similar to mainland France. They presented with immunoglobulin A (IgA) nephropathy and treatment with angiotensin-converting enzyme inhibitor, mevalonate kinase deficiency and treatment with anakinra, chronic idiopathic thrombocytopenic purpura, and history of unilateral partial renal infarction. The 17 other soldiers were referred for dispensation, long-sickness leave granting, or for specification toward administrative coding of their disease. We have described the first exhaustive study of specialized fitness decisions referred to an internal medicine department. One-third of the referred patients were declared fit to serve in the armed forces. Further studies are needed to confirm these results, as our study was monocentric. Fitness decisions must take into account the disease, the treatment, and the operational field characteristics. Soldiers with systemic diseases controlled by immunosuppressive agents can serve in tropical areas if they can reach adequate sanitary structures in a short time. The knowledge of systemic diseases as well as the skillfulness of the internists, which are regularly projected to the operational fields, allows them to provide pragmatic fitness expertise to myriad complex situations.

Analysis of MVK gene variant in a child with high IgD syndrome caused by mevalonate kinase deficiency

To analyze the clinical and genetic features of a patient with mevalonate kinase deficiency (MKD). Whole exome sequencing was carried out for the proband. Candidate variant was verified by Sanger sequencing. The proband was found to harbor compound heterozygous variants of the MVK gene, including a c.248C>T (p.Phe83Cys) variant derived from his father and a c.971C>T (p.Ala324Val) variant from his mother. Based on the guidelines of the American College of Medical Genetics and Genomics, both variations were predicted to be likely pathogenic (PM1 + PM2 + PM3 + PP3). The compound heterozygous variants of the MVK gene probably underlay the MKD in the proband. Above findings have enriched the mutational spectrum of the MVK gene.

De novo assembly and analysis of Polygonatum cyrtonema Hua and identification of genes involved in polysaccharide and saponin biosynthesis

BackgroundThe investigation of molecular mechanisms involved in polysaccharides and saponin metabolism is critical for genetic engineering of Polygonatum cyrtonema Hua to raise major active ingredient content. Up to now, the transcript sequences are available for different tissues of P. cyrtonema, a wide range scanning about temporal transcript at different ages’ rhizomes was still absent in P. cyrtonema.ResultsTranscriptome sequencing for rhizomes at different ages was performed. Sixty-two thousand six hundred thirty-five unigenes were generated by assembling transcripts from all samples. A total of 89 unigenes encoding key enzymes involved in polysaccharide biosynthesis and 56 unigenes encoding key enzymes involved in saponin biosynthesis. The content of total polysaccharide and total saponin was positively correlated with the expression patterns of mannose-6-phosphate isomerase (MPI), GDP-L-fucose synthase (TSTA3), UDP-apiose/xylose synthase (AXS), UDP-glucose 6-dehydrogenase (UGDH), Hydroxymethylglutaryl CoA synthase (HMGS), Mevalonate kinase (MVK), 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (ispF), (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase (ispG), 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (ispH), Farnesyl diphosphate synthase (FPPS). Finally, a number of key genes were selected and quantitative real-time PCR were performed to validate the transcriptome analysis results.ConclusionsThese results create the link between polysaccharides and saponin biosynthesis and gene expression, provide insight for underlying key active substances, and reveal novel candidate genes including TFs that are worth further exploration for their functions and values.

Analysis of clinical characteristics of 35 inflammasomopathies cases

Objective: To summarize the clinical characteristics of inflammasomopathies, enhance the recognition of those diseases, and help to establish the early diagnosis. Methods: The clinical manifestations including fever, rash, systems involvement as well as laboratory results and genotypic characteristics of 35 children with inflammasomopathies diagnosed by the Department of Pediatrics, Peking Union Medical College Hospital, from January 1, 2008 to December 31, 2020 were analyzed retrospectively. Results: A total of 35 cases of inflammasomopathies were diagnosed, and 20 of them were boys while 15 were girls. Inflammasomopathies patients have early onset, the age of onset as well as diagnostic age were 1 (0,7) and 7 (3,12), respectively. Among those patients, 10 had familial mediterranean fever, 3 had mevalonate kinase deficiency, 15 cases had NLRP3 gene associated autoinflammatory disease, 4 cases had NLRP12-associated autoinflammatory disease, 2 cases had familial cold autoinflammatory syndrome 3, and 1 case had familial cold autoinflammatory syndrome 4. A total of 34 cases (97%) showed recurrent fever, 27 cases (77%) had skin rashes, while 11 cases (31%), 10 cases (29%), and 8 cases (23%) were presented with lymphadenopathy, hepatosplenomegaly and growth retardation, respectively. In terms of systemic involvement, there were 18 cases (51%), 12 cases (34%), 8 cases (23%), and 5 cases (14%) with skeletal, neurological, auditory, and renal involvement, respectively. Central nervous system involvement was seen only in NLRP3 gene associtated autoinflammatory diseases (12 cases), sensorineural deafness was seen in NLRP3 gene associtated autoinflammatory diseases (6 cases) and NLRP12 gene associated autoinflammatory diseases (2 cases), and abdominal pain was observed in familial Mediterranean fever (5 cases), mevalonate kinase deficiency (1 case) and NLRP12 gene related autoinflammatory diseases (1 case). In the acute inflammatory phase, the acute phase reactants (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)) of 35 cases (100%) were significantly increased. There were 21 cases received ferritin examination, and only 4 cases (19%) showed an increase of it. In terms of autoantibodies, among all 35 patients, 4 cases (11%) were positive for antinuclear antibodies (ANA). Conclusions: Fever, skin rash, and skeletal manifestations are the most common clinical features, accompanied with increased CRP and ESR, and negative results of autoantibodies such as ANA. The clinical manifestations of those diseases are complex and diverse, and it is prone to delayed diagnosis and treatment.

Engineering Lactococcus lactis as a Cell Factory for the Production of Limonene

Limonene is a plant monoterpene which contributes significantly to the scent of most essential oils due to its pleasant fragrance. The compound had been reported to have anti-cancer properties against several types of cancer including colorectal cancer. However, the production of this compound in nature is limited because it is produced as a secondary metabolite. To overcome these challenges, Lactococcus lactis was developed as a heterologous host for the production of limonene. A synthesized limonene synthase (LS) from Mentha spicata (mint) was cloned into L. lactis NZ9000. Western blot analysis using mouse IgG His-Tag monoclonal antibody showed successful LS expression by L. lactis at the size of ~55 kDa. GC-MS analysis results showed that limonene production was optimum after 24 h of induction (~8.0 ppm). Metabolic engineering was attempted to enhance the limonene production by overexpression of lactococcal 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) and mevalonate kinase (mvk) genes in the bacterial host. The recombinant L. lactis carrying pNZ:LSMM plasmid successfully enhanced the limonene production to two-fold (~15.1 ppm) after 24 h of induction. The outcomes of this study show the potential of L. lactis to produce plant proteins and bioactive compounds production, which prospectively leads to an oral delivery system for anti-cancer compounds.

Activation of the plant mevalonate pathway by extracellular ATP

The mevalonate pathway plays a critical role in multiple cellular processes in both animals and plants. In plants, the products of this pathway impact growth and development, as well as the response to environmental stress. A forward genetic screen of Arabidopsis thaliana using Ca2+-imaging identified mevalonate kinase (MVK) as a critical component of plant purinergic signaling. MVK interacts directly with the plant extracellular ATP (eATP) receptor P2K1 and is phosphorylated by P2K1 in response to eATP. Mutation of P2K1-mediated phosphorylation sites in MVK eliminates the ATP-induced cytoplasmic calcium response, MVK enzymatic activity, and suppresses pathogen defense. The data demonstrate that the plasma membrane associated P2K1 directly impacts plant cellular metabolism by phosphorylation of MVK, a key enzyme in the mevalonate pathway. The results underline the importance of purinergic signaling in plants and the ability of eATP to influence the activity of a key metabolite pathway with global effects on plant metabolism.

Abstracts from the ISSAID 2021 Periodic Congress

Abstracts from the ISSAID 2021 Periodic Congress

L’esofagite eosinofila: quando deglutire diventa difficile

Knowledge in the genetic field of autoinflammatory diseases has progressively increased over the last decade. Starting from the genetic knowledge on a few initially known diseases (Familial Mediterranean Fever, Periodic Syndrome Associated with Tumor Necrosis Factor Receptor 1, Mevalonate Kinase Deficiency, Cryopyrinopathies), at least 40 genes associated with these conditions have been identified, and more than 100 genes are currently being tested with Next Generation Sequencing (NGS) technologies. Indeed, starting recommendations for the genetic diagnosis of autoinflammatory diseases were limited to a gene-by-gene diagnosis strategy, based on the Sanger method, and restricted to a few prototypic recurrent fevers. More recently, improvement of genetic technologies, in particular NGS, allowed identification of genetic variants among involved genes in an easier and more rapid way. Detection of more and more genetic variants made interpretation of results more complicated, and often a genetic diagnosis is not achieved. On the other hand, other mechanisms, namely somatic mosaicisms, epigenetic modifications, digenic inheritance, allow to explain some not genetically defined cases. Eventually, further genetic and non-genetic mechanisms will be probably identified in near future to explain underlying basis of autoinflammatory diseases, especially in a still large part of patients without a clearcut genetic basis.

Comparative Transcriptome Analysis of Genes Involved in Sesquiterpene Alkaloid Biosynthesis in Trichoderma longibrachiatum MD33 and UN32

Trichoderma longibrachiatum MD33, a sesquiterpene alkaloid-producing endophyte isolated from Dendrobium nobile, shows potential medical and industrial applications. To understand the molecular mechanisms of sesquiterpene alkaloids production, a comparative transcriptome analysis was performed on strain MD33 and its positive mutant UN32, which was created using Ultraviolet (UV) mutagenesis and nitrogen ion (N+) implantation. The alkaloid production of UN32 was 2.62 times more than that of MD33. One thousand twenty-four differentially expressed genes (DEGs), including 519 up-regulated and 505 down-regulated genes, were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed 139 GO terms and 87 biosynthesis pathways. Dendrobine, arguably the main sesquiterpene alkaloid the strain MD33 produced, might start synthesis through the mevalonate (MVA) pathway. Several MVA pathway enzyme-coding genes (hydroxy-methylglutaryl-CoA synthase, mevalonate kinase, and farnesyl diphosphate synthase) were found to be differentially expressed, suggesting that physical mutagenesis can disrupt genome integrity and gene expression. Some backbone post-modification enzymes and transcript factors were either discovered, suggesting the sesquiterpene alkaloid metabolism in T. longibrachiatum is a complex genetic network. Our findings help to shed light on the underlying molecular regulatory mechanism of sesquiterpene alkaloids production in T. longibrachiatum.

Transcriptional and Histochemical Signatures of Bone Marrow Mononuclear Cell-Mediated Resolution of Synovitis.

Osteoarthritis (OA) may result from impaired ability of synovial macrophages to resolve joint inflammation. Increasing macrophage counts in inflamed joints through injection with bone marrow mononuclear cells (BMNC) induces lasting resolution of synovial inflammation. To uncover mechanisms by which BMNC may affect resolution, in this study, differential transcriptional signatures of BMNC in response to normal (SF) and inflamed synovial fluid (ISF) were analyzed. We demonstrate the temporal behavior of co-expressed gene networks associated with traits from related in vivo and in vitro studies. We also identified activated and inhibited signaling pathways and upstream regulators, further determining their protein expression in the synovium of inflamed joints treated with BMNC or DPBS controls. BMNC responded to ISF with an early pro-inflammatory response characterized by a short spike in the expression of a NF-ƙB- and mitogen-related gene network. This response was associated with sustained increased expression of two gene networks comprising known drivers of resolution (IL-10, IGF-1, PPARG, isoprenoid biosynthesis). These networks were common to SF and ISF, but more highly expressed in ISF. Most highly activated pathways in ISF included the mevalonate pathway and PPAR-γ signaling, with pro-resolving functional annotations that improve mitochondrial metabolism and deactivate NF-ƙB signaling. Lower expression of mevalonate kinase and phospho-PPARγ in synovium from inflamed joints treated with BMNC, and equivalent IL-1β staining between BMNC- and DPBS-treated joints, associates with accomplished resolution in BMNC-treated joints and emphasize the intricate balance of pro- and anti-inflammatory mechanisms required for resolution. Combined, our data suggest that BMNC-mediated resolution is characterized by constitutively expressed homeostatic mechanisms, whose expression are enhanced following inflammatory stimulus. These mechanisms translate into macrophage proliferation optimizing their capacity to counteract inflammatory damage and improving their general and mitochondrial metabolism to endure oxidative stress while driving tissue repair. Such effect is largely achieved through the synthesis of several lipids that mediate recovery of homeostasis. Our study reveals candidate mechanisms by which BMNC provide lasting improvement in patients with OA and suggests further investigation on the effects of PPAR-γ signaling enhancement for the treatment of arthritic conditions.

Engineering Rhodosporidium toruloides for limonene production

BackgroundLimonene is a widely used monoterpene in the production of food, pharmaceuticals, biofuels, etc. The objective of this work was to engineer Rhodosporidium toruloides as a cell factory for the production of limonene.ResultsBy overexpressing the limonene synthase (LS), neryl pyrophosphate synthase (NPPS)/geranyl pyrophosphate synthase and the native hydroxy-methyl-glutaryl-CoA reductase (HMGR), we established a baseline for limonene production based on the mevalonate route in Rhodosporidium toruloides. To further enhance the limonene titer, the acetoacetyl-CoA thiolase/HMGR (EfMvaE) and mevalonate synthase (EfMvaS) from Enterococcus faecalis, the mevalonate kinase from Methanosarcina mazei (MmMK) and the chimeric enzyme NPPS-LS were introduced in the carotenogenesis-deficient strain. The resulting strains produced a maximum limonene titer of 393.5 mg/L.ConclusionIn this study, we successfully engineered the carotenogenesis yeast R. toruloides to produce limonene. This is the first report on engineering R. toruloides toward limonene production based on NPP and the fusion protein SltNPPS-CltLS. The results demonstrated that R. toruloides is viable for limonene production, which would provide insights into microbial production of valuable monoterpenes.

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.

Performance of recent PRINTO criteria versus current ILAR criteria for systemic juvenile idiopathic arthritis: A single-centre experience.

The purpose of this study is to evaluate the performances of recently proposed Pediatric Rheumatology International Trials Organization criteria versus current International League of Associations for Rheumatology criteria for systemic juvenile idiopathic arthritis (sJIA). The study was performed at the Department of Pediatric Rheumatology in Istanbul Faculty of Medicine with a retrospective design, covering the date range 2010-2021. Patients diagnosed with sJIA, Kawasaki disease and common autoinflammatory diseases were included. Both the International League of Associations for Rheumatology and Pediatric Rheumatology International Trials Organization classification criteria were applied to each patient and cross-checked with expert rheumatologist diagnosis. Eighty-two patients with sJIA were compared against 189 (74 Kawasaki disease, 83 familial Mediterranean fever, 16 mevalonate kinase deficiency, 10 cryopyrin-associated periodic syndromes, and 6 tumour necrosis factor receptor-associated periodic syndrome) patients. The Pediatric Rheumatology International Trials Organization criteria demonstrated higher sensitivity (62.2% vs 80.5%, P =.003) but comparable specificity (90.5% vs 91%) as regards the International League of Associations for Rheumatology criteria. The revised criteria appear to enhance the ability to provide early recognition and pertinent classification of sJIA. No superiority was observed in segregating sJIA from common autoinflammatory diseases and Kawasaki disease, namely in terms of specificity.

Vasculitis in a patient with mevalonate kinase deficiency (MKD): a case report

BackgroundMevalonate kinase deficiency (MKD) is a rare autoinflammatory condition caused by biallelic loss-of-function (LOF) mutations in mevalonate kinase (MVK) gene encoding the enzyme mevalonate kinase. Patients with MKD display a variety of non-specific clinical manifestations, which can lead to diagnostic delay. We report the case of a child presenting with vasculitis that was found by genetic testing to be caused by MKD, and now add this autoinflammatory disease to the ever-expanding list of causes of monogenic vasculitides.Case presentationA 2-year-old male presented with an acute 7-day history of high-grade fever, abdominal pain, diarrhoea, rectal bleeding and extensive purpuric and necrotic lesions, predominantly affecting the lower limbs. He had been suffering from recurrent episodes of fever from early in infancy, associated with maculopapular/petechial rashes triggered by intercurrent infection, and after vaccines. Extensive infection screen was negative. Skin biopsy revealed small vessel vasculitis. Visceral digital subtraction arteriography was normal. With a diagnosis of severe idiopathic cutaneous vasculitis, he was treated with corticosteroids and mycophenolate mofetil. Despite that his acute phase reactants remained elevated, fever persisted and the vasculitic lesions progressed. Next-generation sequencing revealed compound heterozygous mutation in MVK c.928G > A (p.V310M) and c.1129G > A (p.V377I) while reduced mevalonate enzyme activity was confirmed suggesting a diagnosis of MKD as a cause of the severe vasculitis. Prompt targeted treatment with IL-1 blockade was initiated preventing escalation to more toxic vasculitis therapies and reducing unnecessary exposure to cytotoxic treatment.ConclusionsOur report highlights the broad clinical phenotype of MKD that includes severe cutaneous vasculitis and emphasizes the need to consider early genetic screening for young children presenting with vasculitis to exclude a monogenic vasculitis which may be amenable to targeted treatment.

Influence of Polysaccharides From Polygonatum kingianum on Short-Chain Fatty Acid Production and Quorum Sensing in Lactobacillus faecis

Polysaccharide is one of the main active ingredients of Polygonatum kingianum, which has been proven to regulate the balance of gut microbiota. For the first time, this study focused on the regulation of polysaccharides from Polygonatum kingianum (PS) on Lactobacillus faecis, a specific probiotic in the intestinal tract. PS effectively promoted the biomass, biofilm and acetic acid production in L. faecis 2-84, and enhanced quorum sensing (QS) signaling. The characteristics of gene sequence were analyzed using genomics approaches, and L. faecis 2-84 was found to encode 18 genes that are closely related to QS and 10 genes related to short-chain fatty acids (SCFAs). Additionally, transcriptome and proteome analysis demonstrated that PS could promote the QS system of L. faecis by enhancing the transcription of oppA gene and expression of oppD protein. PS also regulated the production and metabolism of SCFAs of L. faecis by upregulating the expression of ldh and metE gene and adh2 protein, and downregulating the expression of mvK gene. In conclusion, it was speculated that PS could affect intestinal SCFAs production by affecting the QS system and SCFAs production in L. faecis. The present study implied that PS might have a role in promoting the growth of intestinal probiotics, where the QS system and SCFAs might be two of the important mechanisms for the probiotic activity of PS.

O007. Register of hereditary auto-inflammatory diseases in a pediatric rheumatology unit

Abstract Background Autoinflammatory diseases (AID) are a group of genetic syndromes resulting from an excessive activation of the innate immune system, caused by mutations in genes regulating the inflammatory pathways and can involve several organs. The aim of this study is to evaluate the clinical, paraclinical, epidemiogical and genetic data of Moroccan patients with confirmed AID, in order to allow a first experience of AID registry in our unit. Material We have retrospectively analyzed 30 cases of patients in our unit over a period of 13 years (between 2006 and 2019), according to inclusion criterias (recurrent fever > 3 episodes and a CRP > 40mg/L) and having excluded immune deficiency, autoimmune disease, neoplasia and infectious diseases. Results The mean age of our patients at 1st consultation was 6.9 years (with extremes ranging from 8 months to 14 years). Consanguinity was reported in 16 cases, and unknown in one case of an adopted child. The patients were classified as follows: 66% of cases with Familial Mediterranean Fever (FMF) including 1 case with a characteristic phenotype of Marshall/Periodic Fever Aphtous Pharyngitis Adenitis (PFAPA) syndrome, 16% of cases with Mevalonate Kinase Deficiency (MKD), 10% of cases with Chronic Recurrent Multifocal Osteomyelitis (CRMO), 1 patient with Familial Pustular Psoriasis (FPP) and another symptomatic patient with Muckle Wells syndrome. An association with Henoch Schonlein purpura was reported in 30% of cases and with periarteritis nodosa in 1 case in FMF patients. The mean diagnostic delay was 3 years (with extremes ranging from 1 month to 12 years). The main clinical features found in our patients included fever (83%), abdominal pain (90%), arthralgia (83%), arthritis (46%), adenopathies (40%), aphtous (30%) and other specific signs. Genetic analysis revealed that M694V was the most frequent mutation (60%), followed by A744S (15%), E148Q (10%), K695R (10%) and P369S/ R408Q (5%) in all FMF patients, and V337I found in 1 patient with MKD while the 4 others were confirmed basing on a high rate of urinary mevalonic acid. CRMO patients were confirmed by radiological and histological analysis. The case of FPP was confirmed histologically by skin biopsy and the patients with Muckle Wells and PFAPA syndroms were diagnosed basing on characteristic clinical features. Therapeutically, all FMF patients were treated with colchicine in addition of corticosteroids in 1 case of PFAPA syndrome. Patients with MKD received targeted therapy (Anakinra, Etanercept) and Ibuprofen in 1 case. CRMO patients were treated with targeted therapy and NSAIDs. The case of FPP was treated with Methotrexate combined with Etanercept and the patient with Muckel Wells Syndrome received corticosteroid therapy combined with Azathioprine and then Anakinra. The clinical and biological evolution was considered favorable in 76% of cases, partial in 13% of cases and 3 death cases were reported. Conclusion AIDs remain rare genetic syndromes whose lack of knowledge explains the late diagnostic delay. Therefore, it is necessary for any pediatrician to know how to evoke an AID in front of recurrent fever with free intervals, clinical features and inflammatory syndrome, in order to choose the optimal treatment as well as to make the genetic counseling. Abbreviations AID: Auto-Inflammatory Disease CAPS: Cryopyrin Associated Periodic Syndromes CARD14: Caspase Recruitment Domain Family Member 14 CIAS1: Cold-Induced Autoinflammatory Syndrome 1 CRMO: Chronic Recurrent Multifocal Osteomyelitis CRP: C-Reactive Protein CT scan: Computerized Tomography scan DNA: DeoxyriboNucleic Acid ESR: Erythrocyte Sedimentation Rate FMF: Familial Mediterranean Fever FPP: Familial Pustular Psoriasis IL-1β: Interleukine-1beta IL-17A: Interleukine 17A MEFV: Mediterranean fever gene MKD: Mevalonate Kinase Deficiency MVK: Mevalonate Kinase MW: Muckle Wells NALP3: NAcht Leucine-rich repeat Protein 3 NLRP3: NOD-like receptor family, pyrin domain containing 3 NSAID: Non-Steroidal Anti Inflammatory Drugs PFAPA: Periodic Fever Aphtous Pharyngitis Adenitis PRINTO: Pediatric Rheumatology INternational Trials Organization SAA: Serum Amyloid A TRAPS: TNF Receptor Associated Periodic Syndroms TNF: Tumor Necrosis Factor

Real-Life Indications of Interleukin-1 Blocking Agents in Hereditary Recurrent Fevers: Data From the JIRcohort and a Literature Review.

BackgroundInterleukin (IL)-1 inhibitors represent the main treatment in patients with colchicine-resistant/intolerant familial Mediterranean fever (crFMF), mevalonate kinase deficiency (MKD), and tumor necrosis factor receptor-associated periodic syndrome (TRAPS). However, the reasons for the use of IL-1 inhibitors in these diseases are still not completely clarified.ObjectiveIdentify real-life situations that led to initiating anakinra or canakinumab treatment in hereditary recurrent fevers (HRFs), combining data from an international registry and an up-to-date literature review.Patients and MethodsData were extracted from the JIRcohort, in which clinical information (demographic data, treatment, disease activity, and quality of life) on patients with FMF, MKD, and TRAPS was retrospectively collected. A literature search was conducted using Medline, EMBASE, and Cochrane databases.ResultsComplete data of 93 patients with HRF (53.8% FMF, 31.2% MKD, and 15.1% TRAPS) were analyzed. Data from both the registry and the literature review confirmed that the main reasons for use of IL-1 blockers were the following: failure of previous treatment (n = 57, 61.3% and n = 964, 75.3%, respectively), persistence of disease activity with frequent attacks (n = 44, 47.3% and n = 1,023, 79.9%) and/or uncontrolled inflammatory syndrome (n = 46, 49.5% and n = 398, 31.1%), severe disease complication or associated comorbidities (n = 38, 40.9% and n = 390, 30.4%), and worsening of patients’ quality of life (n = 36, 38.7% and n = 100, 7,8%). No reasons were specified for 12 (16.4%) JIRcohort patients and 154 (12%) patients in the literature.ConclusionIn the absence of standardized indications for IL-1 inhibitors in crFMF, MKD, and TRAPS, these results could serve as a basis for developing a treat-to-target strategy that would help clinicians codify the therapeutic escalation with IL-1 inhibitors.

P084 Recurrent fever in children: why not a mevalonate kinase deficiency?

Abstract Background Mevalonate kinase deficiency (MKD) is a rare autosomal recessive auto inflammatory disease. The clinical spectrum of this disease is a continuum ranging from the moderate form of Hyper-IgD syndrome (HIDS) to lethal forms of mevalonic aciduria (MA). An autoinflammatory disease should be considered in children with recurrent fever of unexplained origin. Case report M, 28 months old boy from a non-consanguineous marriage of Algerian parents, presented since the age of two months’ episodes of unexplained fever resistant to antibiotics and requiring several hospitalizations. Family history found that the mother and a maternal uncle experienced an unexplained recurrent fever. Personal history found episodes of fever lasting in average 6 days, with no obvious cause and recurring every 15–20 days; associated with bilateral cervical adenopathy, mouth ulcers, arthralgia, abdominal pain with vomiting and diarrhea. Clinical examination confirmed the fever with temperature of 38.7°, Chills and irritability, Multiple cervical adenopathy oral aphthae, tongue of geographical aspect, cervical pain and large joint arthralgia, tender abdomen with no organomegaly. Biologic workups found major inflammatory syndrome with hyper leucocytosis at 14X103/mm3 predominantly polynuclear, high CRP level, high ESR at 110 mm. Blood cultures and viral serologies were negative. Immunoelectrophoresis found elevated IgA, IgG and IgM with a normal IgD level. Chest X-ray and abdominal ultrasound were normal. The diagnosis of MKD in its moderate form was supported by elevated urinary mevalonic acid excretion to 5.1 mmol/mol during the febrile episode and subsequently confirmed by a 2nd contributory urine assay during another febrile episode. Conclusion MKD is a rare disease. The clinical spectrum of this condition is variable and could benefit of an effective treatment. Our patient developed a moderate form with a better long-term prognosis.

Circulating Primitive Erythroblasts in the Murine Embryo Undergo Complex Proteomic and Metabolomic Changes during Terminal Maturation

Primitive erythropoiesis is a critical component of the fetal cardiovascular network and is essential for growth and survival of the mammalian embryo. The need to rapidly establish a functional cardiovascular system in the post-implantation murine embryo is met, in part, by the intravascular circulation of primitive erythroid precursors that mature as a single semi-synchronous cohort. To better understand the processes that regulate erythroid precursor maturation, we analyzed the proteome, metabolome and lipidome of primitive erythroblasts isolated from embryonic day (E)10.5 and E12.5 of mouse gestation, which represents their transition from basophilic erythroblast (BasoE) to orthochromatic erythroblast (OrthoE) stages of maturation. Previous transcriptional and biomechanical characterization of these precursors has highlighted a transition towards the expression of protein elements characteristic of mature red blood cell structure and function, including initial formation of a functional erythroid-specific cytoskeleton. Our analysis confirmed a loss of organelle-specific protein components - from mRNA maturation to translation, from metabolism to protein degradation - including ribosome, spliceosome, mitochondria and proteasomes. In parallel, we observed a metabolic rewiring towards the pentose phosphate pathway, glycolysis and the Rapoport-Luebering shunt, which is consistent with the progressively decreasing steady state levels of carboxylic acids, acylcarnitines and free fatty acids along with decreased mitochondrial content. In addition, activation of the pentose phosphate pathway in particular may stem from increases in the expression of mature red blood cell components including hemoglobin chains and band 3 that control oxygen-dependent metabolic modulation. Furthermore, this metabolic reprogamming may reflect increased control of oxidative stress in line with increased expression of several antioxidant enzymes, including catalase, peroxiredoxins and glutathione peroxidase 4. On the other hand, accumulation of oxylipins and cholesteryl esters in primitive OrthoE cells was paralleled by increased transcript levels of the p53-regulated cholesterol transporter (ABCA1) and decreased transcript levels of cholesterol synthetic enzymes including mevalonate kinase (MVK) and phosphomevalonate kinase (PVMK), highlighting transcriptional control of metabolic reprogramming during this developmental process. The present study characterizes the extensive metabolic rewiring that occurs in primary embryonic erythroid precursors as they prepare to enucleate and continue circulating without internal organelles. DisclosuresNemkov: Omix Thecnologies: Other: Co-founder. Hansen: Omix Technologies: Other: Co-founder; ScalmiBio: Membership on an entity's Board of Directors or advisory committees. Palis: Rubius Therapeutics: Consultancy. D'Alessandro: Omix Thecnologies: Other: Co-founder; Rubius Therapeutics: Consultancy; Forma Therapeutics: Membership on an entity's Board of Directors or advisory committees.

Canakinumab improves patient-reported outcomes in children and adults with autoinflammatory recurrent fever syndromes: results from the CLUSTER trial.

To evaluate the effect of canakinumab on health-related quality of life (HRQoL), work/school and social life of patients with autoinflammatory recurrent fever syndromes, including colchicine-resistant familial Mediterranean fever, mevalonate kinase deficiency, and tumour necrosis factor receptor-associated periodic syndrome, in the CLUSTER trial. HRQoL of patients who received canakinumab 150 mg or 300 mg every four weeks in the CLUSTER trial (n=173) was assessed at baseline and Weeks 17 and 41. For children we used the Child Health Questionnaire - Parent Form 50 (CHQ-PF50), including psychosocial (PsS) and physical (PhS) component summary scores. For adults, the Short-Form-12 (SF-12) Health Survey was used, including physical (PFS) and mental (PCS) component summary scores. The Sheehan Disability Scale (SDS) was used to determine the impact of treatment on work/school, social and family life. The results obtained were remarkably consistent in both paediatric and adult patients across the three disease cohorts. At baseline, median scores for physical components were relatively low (26-29 for PhS and 34-38 for PFS); they improved to values similar to those expected in the general population by Week 17, and this improvement was sustained at Week 41, when median PhS scores were 47-50 and PFS 44-54. Psychosocial and mental scores also improved from baseline to Week 17 and 41, with scores comparable to the general population. Notable improvements were also observed in the SDS scale. Patients with three inherited autoinflammatory syndromes experienced sustained improvements on their HRQoL, work/school, and social life on treatment with canakinumab.