The intestinal microflora in allergic Estonian and Swedish 2-year-old children

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study design
Citation
PMID PubMed identifier for scientific articles.
DOI Digital object identifier for electronic documents.
URI Uniform resource identifier for web resources.
Authors
Björkstén B, Naaber P, Sepp E, Mikelsaar M
Journal
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology
Year
1999
BACKGROUND: The prevalence of allergic diseases seems to have increased particularly over the past 35-40 years. Furthermore, allergic disease is less common among children in the formerly socialist countries of central and Eastern Europe as compared with Western Europe. It has been suggested that a reduced microbial stimulation during infancy and early childhood would result in a slower postnatal maturation of the immune system and development of an optimal balance between TH1- and TH2-like immunity. AIMS: To test the hypothesis that allergic disease among children may be associated with differences in their intestinal microflora in two countries with a low (Estonia) and a high (Sweden) prevalence of allergy. METHODS: From a prospective study of the development of allergy in relation to environmental factors, 29 Estonian and 33 Swedish 2-year-old children were selected. They were either nonallergic (n = 36) or had a confirmed diagnosis of allergy (n = 27) as verified by typical history and at least one positive skin prick test to egg or cow's milk. Weighed samples of faeces were serially diluted (10-2-10-9) and grown under anaerobic conditions. The counts of the various genera and species were calculated for each child. In addition, the relative amounts of the particular microbes were expressed as a proportion of the total count. RESULTS: The allergic children in Estonia and Sweden were less often colonized with lactobacilli (P < 0.01), as compared with the nonallergic children in the two countries. In contrast, the allergic children harboured higher counts of aerobic micro-organisms (P < 0. 05), particularly coliforms (P < 0.01) and Staphylococcus aureus (P < 0.05). The proportions of aerobic bacteria of the intestinal flora were also higher in the allergic children (P < 0.05), while the opposite was true for anaerobes (P < 0.05). Similarly, in the allergic children the proportions of coliforms were higher (P < 0. 05) and bacteroides lower (P < 0.05) than in the nonallergic children. CONCLUSIONS: Differences in the indigenous intestinal flora might affect the development and priming of the immune system in early childhood, similar to what has been shown in rodents. The role of intestinal microflora in relation to the development of infant immunity and the possible consequences for allergic diseases later in life requires further study, particularly as it would be readily available for intervention as a means for primary prevention of allergy by the administration of probiotic bacteria.

Experiment 1


Needs review

Curated date: 2021/01/10

Curator: WikiWorks

Revision editor(s): Rimsha, WikiWorks

Subjects

Location of subjects
Estonia
Sweden
Host species Species from which microbiome was sampled (if applicable)
Homo sapiens
Body site Anatomical site where microbial samples were extracted from according to the Uber Anatomy Ontology
Feces Cow dung,Cow pat,Droppings,Dung,Excrement,Excreta,Faeces,Fecal material,Fecal matter,Fewmet,Frass,Guano,Matières fécales@fr,Merde@fr,Ordure,Partie de la merde@fr,Piece of shit,Porción de mierda@es,Portion of dung,Portion of excrement,Portion of faeces,Portion of fecal material,Portion of fecal matter,Portion of feces,Portion of guano,Portion of scat,Portionem cacas,Scat,Spoor,Spraint,Stool,Teil der fäkalien@de,Feces
Condition The experimental condition / phenotype studied according to the Experimental Factor Ontology
food allergy Food Hypersensitivity,Food intolerance,food allergy
Group 0 name Corresponds to the control (unexposed) group for case-control studies
nonallergic
Group 1 name Corresponds to the case (exposed) group for case-control studies
allergic
Group 1 definition Diagnostic criteria applied to define the specific condition / phenotype represented in the case (exposed) group
child with allergy
Group 0 sample size Number of subjects in the control (unexposed) group
35
Group 1 sample size Number of subjects in the case (exposed) group
27


Statistical Analysis

Statistical test
T-Test
Significance threshold p-value or FDR threshold used for differential abundance testing (if any)
0.05
MHT correction Have statistical tests be corrected for multiple hypothesis testing (MHT)?
No



Signature 1

Needs review

Curated date: 2021/01/10

Curator: Lucy Mellor

Revision editor(s): WikiWorks

Source: Figure 3, text

Description: Relative amounts of aerobic and anaerobic microorganisms in allergic and nonallergic 2-year old children

Abundance in Group 1: increased abundance in allergic

NCBI Links
Enterobacterales

Revision editor(s): WikiWorks

Signature 2

Needs review

Curated date: 2021/01/10

Curator: Lucy Mellor

Revision editor(s): WikiWorks

Source: Figure 3, text

Description: Relative amounts of aerobic and anaerobic microorganisms in allergic and nonallergic 2-year old children

Abundance in Group 1: decreased abundance in allergic

NCBI Links
Bacteroides

Revision editor(s): WikiWorks