title: Differences of small intestinal bacteria populations in adults and children with/without celiac disease: effect of age, gluten diet, and disease.
abstract: BACKGROUND
  Scientific evidence has revealed microecological changes in the intestinal tract of celiac infants. The objective of this work is the study of bacterial differences in the upper small intestine in both adults (healthy, untreated celiac disease [CD], and CD treated with a gluten-free diet) and children (healthy and untreated CD).
  
  
  METHODS
  Intestinal bacterial communities were identified by 16S rRNA gene sequencing of DNA extracted from duodenal biopsies.
  
  
  RESULTS
  Analysis of the sequences from adults and children showed that this niche was colonized by bacteria affiliated mainly with three phyla: Firmicutes, Proteobacteria, and Bacteroidetes. In total, 89 different genera were identified in adults and 46 in children. Bacterial richness was significantly lower in the children than in the adults. A global principal component analysis of the bacterial communities of both healthy and untreated CD patient groups (including both children and adults) revealed a strong effect of age in principal component 1--clustering all adults and children separately--and a possible effect of the disease in adults with untreated patients clustering separately.
  
  
  CONCLUSIONS
  There are bacterial differences in the upper small intestine between untreated children CD patients and untreated CD adults due to age. There are bacterial differences in the upper small bacteria microbiota between treated and untreated CD adults due to treatment with a gluten-free diet.
authors.affiliation: Área de Microbiología, Facultad de Biología y Ciencias Ambientales, Universidad de León, León, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Nistal
authors.forename: Alberto
authors.initials: A
authors.lastname: Caminero
authors.forename: Alexandra R
authors.initials: AR
authors.lastname: Herrán
authors.forename: Laura
authors.initials: L
authors.lastname: Arias
authors.forename: Santiago
authors.initials: S
authors.lastname: Vivas
authors.forename: José M Ruiz
authors.initials: JM
authors.lastname: de Morales
authors.forename: Sara
authors.initials: S
authors.lastname: Calleja
authors.forename: Luis E Sáenz
authors.initials: LE
authors.lastname: de Miera
authors.forename: Paula
authors.initials: P
authors.lastname: Arroyo
authors.forename: Javier
authors.initials: J
authors.lastname: Casqueiro
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D041963:Bacteroidetes / Q000302:isolation & purification; D044822:Biodiversity; D002446:Celiac Disease / Q000178:diet therapy / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D055050:Diet, Gluten-Free; D005260:Female; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D007421:Intestine, Small / Q000382:microbiology*; D008297:Male; D020560:Proteobacteria / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D055815:Young Adult
chemical_list: D012336:RNA, Ribosomal, 16S