Titre : Carence en vitamine B12

Carence en vitamine B12 : Questions médicales fréquentes

Termes MeSH sélectionnés :

Complement C3
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?\nQuel rôle joue l'historique médical dans le diagnostic ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-diagnostic" }, { "@type": "MedicalWebPage", "name": "Symptômes", "headline": "Symptômes sur Carence en vitamine B12", "description": "Quels sont les symptômes courants de la carence en B12 ?\nLa carence en B12 peut-elle causer des problèmes neurologiques ?\nComment la carence affecte-t-elle la peau ?\nY a-t-il des symptômes digestifs associés ?\nLes symptômes varient-ils selon l'âge ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-symptômes" }, { "@type": "MedicalWebPage", "name": "Prévention", "headline": "Prévention sur Carence en vitamine B12", "description": "Comment prévenir la carence en vitamine B12 ?\nLes personnes âgées doivent-elles prendre des suppléments ?\nLes végétaliens peuvent-ils éviter la carence ?\nLes tests réguliers sont-ils recommandés ?\nLes maladies digestives augmentent-elles le risque ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-prévention" }, { "@type": "MedicalWebPage", "name": "Traitements", "headline": "Traitements sur Carence en vitamine B12", "description": "Comment traiter une carence en vitamine B12 ?\nQuelle est la durée du traitement ?\nLes aliments peuvent-ils aider à corriger la carence ?\nLes personnes végétariennes sont-elles à risque ?\nLes traitements sont-ils différents pour les enfants ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-traitements" }, { "@type": "MedicalWebPage", "name": "Complications", "headline": "Complications sur Carence en vitamine B12", "description": "Quelles complications peuvent survenir ?\nLa carence peut-elle entraîner des problèmes cognitifs ?\nY a-t-il un risque accru de maladies cardiovasculaires ?\nLes complications sont-elles réversibles ?\nLa carence en B12 peut-elle affecter la grossesse ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-complications" }, { "@type": "MedicalWebPage", "name": "Facteurs de risque", "headline": "Facteurs de risque sur Carence en vitamine B12", "description": "Qui est le plus à risque de carence en B12 ?\nLes maladies auto-immunes augmentent-elles le risque ?\nLes médicaments peuvent-ils influencer le risque ?\nLes troubles digestifs sont-ils un facteur de risque ?\nLes antécédents familiaux jouent-ils un rôle ?", "url": "https://questionsmedicales.fr/mesh/D014806?mesh_terms=Complement+C3&page=2#section-facteurs de risque" } ] }, { "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "Comment diagnostiquer une carence en vitamine B12 ?", "position": 1, "acceptedAnswer": { "@type": "Answer", "text": "Un diagnostic se fait par des analyses sanguines mesurant les niveaux de vitamine B12." } }, { "@type": "Question", "name": "Quels tests sont utilisés pour confirmer la carence ?", "position": 2, "acceptedAnswer": { "@type": "Answer", "text": "Les tests incluent la mesure de la vitamine B12, de l'homocystéine et de la méthylmalonyl-CoA." } }, { "@type": "Question", "name": "Quels signes cliniques indiquent une carence ?", "position": 3, "acceptedAnswer": { "@type": "Answer", "text": "Des signes comme l'anémie, la fatigue, et des troubles neurologiques peuvent indiquer une carence." } }, { "@type": "Question", "name": "La carence en B12 peut-elle être asymptomatique ?", "position": 4, "acceptedAnswer": { "@type": "Answer", "text": "Oui, certaines personnes peuvent avoir une carence sans présenter de symptômes visibles." } }, { "@type": "Question", "name": "Quel rôle joue l'historique médical dans le diagnostic ?", "position": 5, "acceptedAnswer": { "@type": "Answer", "text": "L'historique médical aide à identifier des facteurs de risque comme des troubles d'absorption." } }, { "@type": "Question", "name": "Quels sont les symptômes courants de la carence en B12 ?", "position": 6, "acceptedAnswer": { "@type": "Answer", "text": "Les symptômes incluent fatigue, faiblesse, engourdissements et troubles de l'humeur." } }, { "@type": "Question", "name": "La carence en B12 peut-elle causer des problèmes neurologiques ?", "position": 7, "acceptedAnswer": { "@type": "Answer", "text": "Oui, elle peut entraîner des troubles neurologiques comme des démences ou des neuropathies." } }, { "@type": "Question", "name": "Comment la carence affecte-t-elle la peau ?", "position": 8, "acceptedAnswer": { "@type": "Answer", "text": "Elle peut provoquer des changements cutanés comme une pâleur ou des lésions cutanées." } }, { "@type": "Question", "name": "Y a-t-il des symptômes digestifs associés ?", "position": 9, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des symptômes comme des nausées, des diarrhées ou des troubles digestifs peuvent survenir." } }, { "@type": "Question", "name": "Les symptômes varient-ils selon l'âge ?", "position": 10, "acceptedAnswer": { "@type": "Answer", "text": "Oui, les symptômes peuvent être plus prononcés chez les personnes âgées en raison de l'absorption réduite." } }, { "@type": "Question", "name": "Comment prévenir la carence en vitamine B12 ?", "position": 11, "acceptedAnswer": { "@type": "Answer", "text": "Une alimentation équilibrée incluant des sources de B12 et des suppléments si nécessaire aide." } }, { "@type": "Question", "name": "Les personnes âgées doivent-elles prendre des suppléments ?", "position": 12, "acceptedAnswer": { "@type": "Answer", "text": "Oui, les personnes âgées peuvent avoir besoin de suppléments en raison d'une absorption réduite." } }, { "@type": "Question", "name": "Les végétaliens peuvent-ils éviter la carence ?", "position": 13, "acceptedAnswer": { "@type": "Answer", "text": "Ils doivent prendre des suppléments de B12 ou consommer des aliments enrichis pour éviter la carence." } }, { "@type": "Question", "name": "Les tests réguliers sont-ils recommandés ?", "position": 14, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des tests réguliers sont conseillés pour les personnes à risque de carence." } }, { "@type": "Question", "name": "Les maladies digestives augmentent-elles le risque ?", "position": 15, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des maladies comme la maladie de Crohn peuvent affecter l'absorption de la vitamine B12." } }, { "@type": "Question", "name": "Comment traiter une carence en vitamine B12 ?", "position": 16, "acceptedAnswer": { "@type": "Answer", "text": "Le traitement inclut des suppléments oraux ou des injections de vitamine B12 selon la gravité." } }, { "@type": "Question", "name": "Quelle est la durée du traitement ?", "position": 17, "acceptedAnswer": { "@type": "Answer", "text": "La durée dépend de la gravité, mais peut durer de quelques mois à plusieurs années." } }, { "@type": "Question", "name": "Les aliments peuvent-ils aider à corriger la carence ?", "position": 18, "acceptedAnswer": { "@type": "Answer", "text": "Oui, consommer des aliments riches en B12 comme la viande, le poisson et les produits laitiers aide." } }, { "@type": "Question", "name": "Les personnes végétariennes sont-elles à risque ?", "position": 19, "acceptedAnswer": { "@type": "Answer", "text": "Oui, elles peuvent être à risque en raison d'un apport alimentaire limité en vitamine B12." } }, { "@type": "Question", "name": "Les traitements sont-ils différents pour les enfants ?", "position": 20, "acceptedAnswer": { "@type": "Answer", "text": "Les traitements sont similaires, mais les doses peuvent varier selon l'âge et le poids." } }, { "@type": "Question", "name": "Quelles complications peuvent survenir ?", "position": 21, "acceptedAnswer": { "@type": "Answer", "text": "Des complications incluent l'anémie mégaloblastique, des troubles neurologiques et des problèmes cardiaques." } }, { "@type": "Question", "name": "La carence peut-elle entraîner des problèmes cognitifs ?", "position": 22, "acceptedAnswer": { "@type": "Answer", "text": "Oui, une carence prolongée peut causer des troubles cognitifs et des pertes de mémoire." } }, { "@type": "Question", "name": "Y a-t-il un risque accru de maladies cardiovasculaires ?", "position": 23, "acceptedAnswer": { "@type": "Answer", "text": "Oui, une carence en B12 peut augmenter le risque de maladies cardiovasculaires en élevant l'homocystéine." } }, { "@type": "Question", "name": "Les complications sont-elles réversibles ?", "position": 24, "acceptedAnswer": { "@type": "Answer", "text": "Certaines complications peuvent être réversibles avec un traitement approprié, d'autres non." } }, { "@type": "Question", "name": "La carence en B12 peut-elle affecter la grossesse ?", "position": 25, "acceptedAnswer": { "@type": "Answer", "text": "Oui, elle peut entraîner des complications pendant la grossesse, comme des malformations congénitales." } }, { "@type": "Question", "name": "Qui est le plus à risque de carence en B12 ?", "position": 26, "acceptedAnswer": { "@type": "Answer", "text": "Les personnes âgées, les végétariens, et ceux ayant des troubles d'absorption sont à risque." } }, { "@type": "Question", "name": "Les maladies auto-immunes augmentent-elles le risque ?", "position": 27, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des maladies comme la gastrite atrophique peuvent affecter l'absorption de la B12." } }, { "@type": "Question", "name": "Les médicaments peuvent-ils influencer le risque ?", "position": 28, "acceptedAnswer": { "@type": "Answer", "text": "Oui, certains médicaments comme les inhibiteurs de la pompe à protons peuvent réduire l'absorption." } }, { "@type": "Question", "name": "Les troubles digestifs sont-ils un facteur de risque ?", "position": 29, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des troubles comme la maladie cœliaque peuvent nuire à l'absorption de la vitamine B12." } }, { "@type": "Question", "name": "Les antécédents familiaux jouent-ils un rôle ?", "position": 30, "acceptedAnswer": { "@type": "Answer", "text": "Oui, des antécédents familiaux de carence peuvent augmenter le risque chez certains individus." } } ] } ] }

Sources (1986 au total)

Plasma complement C3 and C3a are increased in major depressive disorder independent of childhood trauma.

Dysregulated complement system is linked to pathophysiology of major depressive disorder (MDD). Childhood trauma has been associated with an increased incidence of adult depression via a putative mech... The participants were 49 medication-free MDD patients and 45 healthy controls. All participants were asked to finish the Childhood Trauma Questionnaire, followed by blood sampling for measurement of p... Peripheral plasma concentration of C3 and C3a in medication-free MDD group was significantly higher than that in the healthy controls; whereas the concentration of plasma C1q and CRP in depressed pati... Our data suggest that complement C3 and C3a may be implicated in the pathophysiology of MDD, although traumatic childhood experiences were not associated with the circulating levels of complement C3, ...

Complement gene mutations in children with C3 glomerulopathy: do they affect the response to mycophenolate mofetil?

C3 glomerulopathy (C3G) is a complement-mediated disease. Although genetic studies are not required for diagnosis, they are valuable for treatment planning and prognosis prediction. The aim of this st... Sixty pediatric C3G patients were included, divided into two groups based on complement-related gene mutations. Demographic and clinical-pathological findings, treatment modalities, and outcome data w... Out of the 60 patients, 17 had mutations. The most common mutation was in the CFH gene (47%). The mean age at diagnosis was higher in the group with mutation (12.9 ± 3.6 vs. 11.2 ± 4.1 years, p = 0.03... This study is the largest pediatric C3G study examining the relationship between genotype and phenotype. We showed that the mutation group often presented with asymptomatic urinary abnormalities, was ...

Complement C3 as a potential drug target in periodontitis: Evidence from the cis-Mendelian randomization approach.

Evidence from a Phase IIa trial showed that a complement C3-targeted drug reduced gingival inflammation in patients with gingivitis. Using drug-target Mendelian randomization (MR), we investigated whe... We used multiple 'cis' instruments from the vicinity of the encoding loci of C3. Instrument selection was restricted to the drug target encoding loci (chromosome 19; 6,677,715-6,730,573 (GRCh37/hg19))... MR analysis revealed that the inhibition of C3 reduces the odds of periodontitis (OR 0.91 per 1 standard deviation reduction in C3; 95% confidence interval 0.87-0.96, p value = .0003).... Findings from our MR analysis suggest a potential protective effect of C3 blockade against periodontitis....

Serum C3 complement levels predict prognosis and monitor disease activity in Guillain-Barré syndrome.

Biomarkers are needed to predict prognosis and disease activity in patients with Guillain-Barré syndrome (GBS). The complement system is a key player in the pathogenesis of GBS. This study aimed to as... We reviewed the medical records of 76 GBS patients with C3 and C4 measurements during hospitalization between 2010 and 2021. Clinical outcomes were correlated with baseline serum C3, C4, and seven add... Higher C3, but not C4, was associated with poorer outcomes: lower Medical Research Council sum scores (MRCSS), higher GBS disability score (GBSDS), longer hospitalization, and more frequent treatment-... This study highlights the use of serum C3 as a novel mechanistic biomarker in GBS. Larger prospective studies are needed to validate our findings....

Relationship Between Serum Complement C3 Levels and Outcomes Among Patients With Anti-GBM Disease.

IgG and complement 3 (C3) are generally found to be deposited along the glomerular basement membrane (GBM) in human anti-GBM disease. The pathogenic role of complement activation in kidney damage of a... Ninety-four anti-GBM disease patients between January 2004 and December 2020 at the National Clinical Research Center of Kidney Diseases Jinling Hospital were retrospectively analyzed, and were divide... A total of 94 patients (aged 43.6 ± 16.2; male patients, 46%) with anti-GBM disease were enrolled. There were 26 patients with low C3 levels and 68 patients with normal C3 levels. Compared with the no... The kidney outcomes of anti-GBM disease in the low C3 group were poorer than those in the normal C3 group. The influence of C3 on the kidney outcomes of patients with anti-GBM disease may be of clinic...

Comparative analysis of complement C3 and C4 serum levels for outcome prediction in ANCA-associated renal vasculitis.

The activation of the complement system contributes essentially to the pathogenesis of anti-neutrophil cytoplasmic antibody (ANCA)-associated renal vasculitis. We here aimed to directly compare levels... Serum levels of complement components C3 and C4 were directly compared in association with clinical and outcome data in a retrospective cohort of ANCA-associated renal vasculitis.... As compared to poor outcome prediction by low levels of complement C3 (p = 0.0093), low levels of complement C4 did not associate with early requirement of kidney replacement therapy (KRT) or death (p... While low levels of complement C3 were superior in predicting poor outcome in ANCA-associated renal vasculitis, a minor fraction with poor outcome had isolated C4 lowering not captured by serum C3 mea...

Implication of platelets and complement C3 as link between innate immunity and tubulointerstitial injury in renal vasculitis with MPO-ANCA seropositivity.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a potentially life-threatening systemic small-vessel vasculitis that is characterized by pauci-immune glomerulonephritis, depi... A cohort of 53 biopsy-proven cases of ANCA-associated renal vasculitis were retrospectively enrolled in a single-center observational study. Univariate and multivariate regression analysis was perform... Lower platelet counts correlated with markers of kidney injury including eGFR loss (... Based on our observation that an association between platelets and complement system activation is only observed in the MPO-ANCA subgroup, this could implicate that platelets and complement C3 link in...