Triglycerides and glycated hemoglobin for screening insulin resistance in obese patients

International audienceOBJECTIVE: Assessment of insulin resistance (IR) is essential in non-diabetic patients with obesity. Thus study aims to identify the best determinants of IR and to propose an original approach for routine assessment of IR in obesity. DESIGN AND PATIENTS: All adult with obesity defined by a body mass index >=30kg/m2, evaluated in the Nutrition Department between January 2010 and January 2015 were included in this cross-sectional study. Patients with diabetes were excluded. IR was diagnosed according to the HOMA-IR. Based on a logistic regression, we determined a composite score of IR. We then tested the variables with a principal component analysis and a hierarchical clustering analysis. RESULTS: A total of 498 patients with obesity were included. IR was associated with grade III obesity (OR=2.6[1.6-4.4], p\textless0.001), HbA1c>=5.7% (OR=2.6[1.7-4.0], p\textless0.001), hypertriglyceridemia \textgreater1.7mmol/l (OR=3.0[2.0-4.5], p\textless0.001) and age (OR=0.98[0.96-0.99], p=0.002). Exploratory visual analysis using factor map and clustering analysis revealed that lipid and carbohydrates metabolism abnormalities were correlated with insulin resistance but not with excessive fat accumulation and low-grade inflammation. CONCLUSIONS: Our results highlight the interest of simple blood tests such as HbA1c and triglyceride determination, which associated with BMI, may be widely available tools for screening IR in obese patients

Curation and expansion of the Human Phenotype Ontology for systemic autoinflammatory diseases improves phenotype-driven disease-matching

INTRODUCTION: Accurate and standardized phenotypic descriptions are essential in diagnosing rare diseases and discovering new diseases, and the Human Phenotype Ontology (HPO) system was developed to provide a rich collection of hierarchical phenotypic descriptions. However, although the HPO terms for inborn errors of immunity have been improved and curated, it has not been investigated whether this curation improves the diagnosis of systemic autoinflammatory disease (SAID) patients. Here, we aimed to study if improved HPO annotation for SAIDs enhanced SAID identification and to demonstrate the potential of phenotype-driven genome diagnostics using curated HPO terms for SAIDs. METHODS: We collected HPO terms from 98 genetically confirmed SAID patients across eight different European SAID expertise centers and used the LIRICAL (Likelihood Ratio Interpretation of Clinical Abnormalities) computational algorithm to estimate the effect of HPO curation on the prioritization of the correct SAID for each patient. RESULTS: Our results show that the percentage of correct diagnoses increased from 66% to 86% and that the number of diagnoses with the highest ranking increased from 38 to 45. In a further pilot study, curation also improved HPO-based whole-exome sequencing (WES) analysis, diagnosing 10/12 patients before and 12/12 after curation. In addition, the average number of candidate diseases that needed to be interpreted decreased from 35 to 2. DISCUSSION: This study demonstrates that curation of HPO terms can increase identification of the correct diagnosis, emphasizing the high potential of HPO-based genome diagnostics for SAIDs

ISSAID/EMQN Best Practice Guidelines for the Genetic Diagnosis of Monogenic Autoinflammatory Diseases in the Next-Generation Sequencing Era

Abstract Background Monogenic autoinflammatory diseases are caused by pathogenic variants in genes that regulate innate immune responses, and are characterized by sterile systemic inflammatory episodes. Since symptoms can overlap within this rapidly expanding disease category, accurate genetic diagnosis is of the utmost importance to initiate early inflammation-targeted treatment and prevent clinically significant or life-threatening complications. Initial 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 the 4 prototypic recurrent fevers (MEFV, MVK, TNFRSF1A, and NLRP3 genes). The development of best practices guidelines integrating critical recent discoveries has become essential. Methods The preparatory steps included 2 online surveys and pathogenicity annotation of newly recommended genes. The current guidelines were drafted by European Molecular Genetics Quality Network members, then discussed by a panel of experts of the International Society for Systemic Autoinflammatory Diseases during a consensus meeting. Results In these guidelines, we combine the diagnostic strength of next-generation sequencing and recommendations to 4 more recently identified genes (ADA2, NOD2, PSTPIP1, and TNFAIP3), nonclassical pathogenic genetic alterations, and atypical phenotypes. We present a referral-based decision tree for test scope and method (Sanger versus next-generation sequencing) and recommend on complementary explorations for mosaicism, copy-number variants, and gene dose. A genotype table based on the 5-category variant pathogenicity classification provides the clinical significance of prototypic genotypes per gene and disease. Conclusions These guidelines will orient and assist geneticists and health practitioners in providing up-to-date and appropriate diagnosis to their patients

Obesity and Insulin resistance : which determinants ? : inflammation, fat mass or triglycerides ?

L'obésité est classiquement associée à plusieurs anomalies métaboliques comme l'insulinorésistance, la dyslipidémie et l'inflammation de bas grade, aujourd'hui reconnues comme facteurs de risques cardio-métaboliques. C’est également un composant fondamental du syndrome métabolique, un concept développé pour aider à l'identification des patients à haut risque cardio-métabolique. Pourtant, il existe une sous-population d'obèses dite "métaboliquement saine" qui est associée à un moindre risque. Cette sous-population n'est actuellement toujours pas définie de manière consensuelle mais l'insulinorésistance est essentielle dans les critères d'identification de la "santé métabolique". Une plus forte prévalence de l'insulinorésistance est associée à l'obésité abdominale, principal facteur diagnostique du syndrome métabolique, mais pourtant ces 2 phénotypes ne sont pas synonymes. Nous savons donc qu'il existe une hétérogénéité métabolique chez les patients obèses. Mon projet proposait d'identifier les meilleurs déterminants de l'insulinorésistance chez ces patients. Nous avons mis en évidence que l’inflammation de bas grade était associée aux marqueurs d’adiposité plutôt qu’à l’insulinorésistance, puis que les anomalies des métabolismes des glucides et des lipides, plus particulièrement les triglycérides et l’hémoglobine glyquée A1c, étaient les principaux facteurs associés de l’insulinorésistance chez nos patients obèses. Ceci restaure l’intérêt de ces dosages simples qui, associés à l’indice de masse corporelle, pourraient servir d’outils rapides et peu couteux pour aider le clinicien à identifier les individus insulino-résistants, alors que les nombreuses définitions du phénotype « obèse métaboliquement sain » ne font pas encore consensus.Obesity is classically associated with a constellation of metabolic pattern including insulin-resistance, dyslipidemia and low-grade inflammation, now clustered as cardio-metabolic risk factors. Obesity is also a main component of the metabolic syndrome, which has become one of the major public health challenges in helping identify individuals at high risk of both type 2 diabetes and cardiovascular diseases. However a subgroup of metabolically healthy individuals with obesity (MHO) who might be at lower risk of cardiovascular events has been clinically recognized but no universally accepted criteria exist to define it.Assessment of insulin resistance phenotype is essential, and for most definitions of metabolic health, insulin sensitivity is taken into account. It is well accepted that a higher prevalence of insulin resistance is associated with abdominal obesity measured by waist circumference in routine. Although abdominal adiposity is a major component of the concept of metabolic syndrome, it appears that metabolic syndrome is not synonymous with the insulin resistance phenotype. We can assume that there is heterogeneity in the metabolic status of patients with obesity. Accordingly, the aim of my project was to explore what are the best determinants of insulin resistance in the obesity condition. We showed that inflammation was associated to fat accumulation rather than insulin resistance and that triglycerides and glycated hemoglobin were the factors best correlated to insulin resistance. Finally, a simple blood test as triglycerides and glycated hemoglobin determination could be an easy and available method to help physicians identify obesity related insulin resistance for appropriate prevention

Dépistage de marqueurs cellulaires prédictifs de réponse au traitement par tocilizumab chez des patients atteints de polyarthrite rhumatoïde

MONTPELLIER-BU Pharmacie (341722105) / SudocSudocFranceF

Utilisation des lymphocytes T régulateurs en thérapies cellulaires dans les maladies auto-immunes

 Les lymphocytes T régulateurs (Treg) ont un rôle fondamental dans le maintien de la tolérance immunitaire. Des déficits qualitatifs ou quantitatifs de ces cellules ont été mis en évidence dans les maladies auto-immunes. La thérapie cellulaire par administration de Treg pourrait avoir un effet à long terme. Elle semble donc être une approche séduisante et innovante, ce d’autant que les traitements usuels des maladies auto-immunes sont souvent non curatifs, et doivent être administrés de façon répétée. Des résultats encourageants ont montré que le transfert de Treg naturels (nTreg) CD4+CD25+Foxp3+ ou de certains Treg induits (iTreg) in vitro permettait de ralentir l’évolution de ces pathologies dans des modèles murins. L’objectif de cette revue est de faire un état des lieux sur ces nouvelles thérapies et d’en discuter le potentiel thérapeutique et leurs limites

Actualité sur les lymphocytes T régulateurs CD4

Les lymphocytes T régulateurs (Treg) CD4+ sont impliqués dans le maintien de la tolérance périphérique et la prévention des maladies auto-immunes. Ils régulent également les réponses immunes observées dans les allergies, les greffes, les cancers et les maladies infectieuses. Les lymphocytes T ne forment pas une population homogène, et plusieurs sous-populations de Treg ont été isolées. L’objectif de cette revue est de discuter certains aspects marquants de la biologie des Treg naturels (nTreg), concernant notamment leur caractérisation, leurs principaux rôles dans l’homéostasie physiologique et dans certaines pathologies ainsi que leurs mécanismes d’action. Enfin, nous terminerons cette synthèse par la présentation des Treg induits (iTreg)

Phenotypic Associations of PSTPIP1 Sequence Variants in PSTPIP1-Associated Autoinflammatory Diseases

International audiencePathogenic variants in the PSTPIP1 gene cause pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome. They were also identified in a broad spectrum of phenotypes. As their interpretation is sometimes challenging, we discuss the genotype-phenotype association in PSTPIP1-associated autoinflammatory diseases (PAIDs) in light of a recent consensus classification of variant pathogenicity. Only 7 of 39 (18%) of the PSTPIP1 variants found in all reported cases and our national reference center (161 patients [114 probands]) were pathogenic. They were clearly associated with PAPA and PSTPIP1-associated myeloid-related proteinemia inflammatory syndrome (PAMI), reflecting a variable clinical expression of PAIDs

Mevalonate Kinase-Associated Diseases: Hunting for Phenotype–Genotype Correlation

Mevalonate kinase-associated diseases (MKAD) are caused by pathogenic mutations in the mevalonate kinase gene (MVK) and encompass several phenotypically different rare and hereditary autoinflammatory conditions. The most serious is a recessive systemic metabolic disease called mevalonic aciduria, and the most recently recognized is disseminated superficial actinic porokeratosis, a dominant disease limited to the skin. To evaluate a possible correlation between genotypes and (1) the different MKAD clinical subtypes or (2) the occurrence of severe manifestations, data were reviewed for all patients with MVK variants described in the literature (N = 346), as well as those referred to our center (N = 51). The genotypes including p.(Val377Ile) (homozygous or compound heterozygous) were more frequent in mild systemic forms but were also sometimes encountered with severe disease. We confirmed that amyloidosis was more prevalent in patients compound heterozygous for p.(Ile268Thr) and p.(Val377Ile) than in others and revealed new associations. Patients homozygous for p.(Leu264Phe), p.(Ala334Thr) or compound heterozygous for p.(His20Pro) and p.(Ala334Thr) had increased risk of severe neurological or ocular symptoms. All patients homozygous for p.(Leu264Phe) had a cataract. The variants associated with porokeratosis were relatively specific and more frequently caused a frameshift than in patients with other clinical forms (26% vs. 6%). We provide practical recommendations focusing on phenotype–genotype correlation in MKAD that could be helpful for prophylactic management

The Changing Concepts Regarding the Mediterranean Fever Gene: Toward a Spectrum of Pyrin-Associated Autoinflammatory Diseases with Variable Heredity

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