ABSTRACT
The knowledge regarding celiac disease has increased dramatically in recent years, due to the availability of accurate serologic markers. Mass screening studies have shown that the prevalence of sensitization can be as high as 1/80. The range of symptoms is wide, from the classic growth failure, denutrition and diarrhea in infancy to clinically and histologically asymptomatic sensitized subjects. The interest of a routine mass screening is debated. The classical celiac disease in infancy is well known. Atypical symptoms and potentially associated disease are more frequent and potentially confounding. Physicians should be aware of any clue for celiac disease in atypical cases in order to improve the diagnostic yield, and therefore avoiding short or long term consequences.
Subject(s)
Celiac Disease/diagnosis , Age of Onset , Celiac Disease/classification , Celiac Disease/epidemiology , Celiac Disease/etiology , Child , Down Syndrome/complications , Down Syndrome/epidemiology , Genetic Predisposition to Disease , Humans , Risk Factors , Turner Syndrome/complications , Turner Syndrome/epidemiologySubject(s)
Gastroesophageal Reflux/drug therapy , Inappropriate Prescribing , Proton Pump Inhibitors/therapeutic use , Adolescent , Adult , Child , Child, Preschool , Contraindications , Cross-Sectional Studies , Drug Utilization , Esophagitis, Peptic/drug therapy , Esophagitis, Peptic/epidemiology , Gastroesophageal Reflux/epidemiology , Humans , Infant , Infant, Newborn , Infant, Premature, Diseases/drug therapy , Placebo Effect , Proton Pump Inhibitors/adverse effectsABSTRACT
With the discovery of CARD15 as susceptibility gene for Crohn's disease (CD) a first link to a potential defect in the innate immune system was made. In this work we aimed to analyze enterocyte NOD2/CARD15 expression and regulation in response to bacterial motifs and the consequences of the most common CD-specific CARD15 mutation on antibacterial responses of normal intestinal epithelial cells (IEC). Under normal conditions, IEC lines and ileal enterocytes did not express NOD2/CARD15 mRNA or protein, contrary to IEC derived from inflammatory CD sections. In vitro analyses revealed that the simple contact with non-pathogenic commensal E. Coli K12 was sufficient to induced NOD2/CARD15 mRNA and protein in human IEC (HIEC). We identified bacterial flagellin interacting with TLR5 as major motif in this regulation of NOD2/CARD15. E. Coli mutants not expressing flagellin (DeltaFliC) failed to induce CARD15. Similarly, in HIEC transfected with a plasmid encoding dominant negative TLR5, no CARD15 induction was observed after K12 contact. Isolated TLR2 or TLR4 stimulation had no or only a marginal effect on NOD2/CARD15 expression. NOD2/CARD15 negative HIEC were unresponsive to muramyl dipeptide (MDP), but once NOD2/CARD15 was induced, HIEC and Caco2 cells responded to intra or extracellular MDP presentation with the activation of the NFkB pathway. IEC transfected with the Crohn-specific CARD15 mutant (F3020insC, FS) failed to activate NFkB after MDP-challenge, in contrast to CARD15WT IEC. In response to MDP, IEC induced a massive antibacterial peptide (ABP) response, seen in the apical release of CCL20. This was completely abolished in IEC carrying CARD15FS. These data suggest a critical role of NOD2/CARD15 in the bacterial clearance of the intestinal epithelium while CD-specific mutated NOD2/CARD15 causes an impaired epithelial barrier.