The relationship between the commensal microbiota levels and Crohn's disease activity.

BACKGROUND AND AIM: Human gut microbiota play an important role in metabolism and host physiology. Perturbations of the gut microbial communities lead to the development of various diseases such as inflammatory bowel disease, celiac disease, allergic diseases, and metabolic diseases. Crohn's disease is a chronic inflammatory bowel disease characterized by periods of remission and relapse. Several studies suggest that intestinal inflammation arises due to an abnormal response of the intestinal immune system to the fecal microbiota. The goal of the study was to evaluate the relative amount of four bacterial groups in fecal samples of Crohn's disease patients and their relation to the inflammatory activity. METHODS: We studied stool samples of 105 individuals, 54 with Crohn's disease and 51 as a control group. The DNA extracted from the stool samples was subjected to real-time polymerase chain reaction (qPCR) for quantification of the Bacteroidetes phylum, class Bacilli, and Bifidobacteriaceae and Enterobacteriaceae families. RESULTS: We found a significant increase in Bacteroidetes in Crohn's disease samples when compared to the control group (14 650 and 2060 CFU/ng DNA, respectively) (P = 0.014). On the other hand, we observed a significant reduction in Bacilli and Bifidobacteriaceae (13 and 58 CFU/ng DNA, respectively) (P < 0.0001). In contrast, patients without any drug treatment presented an increase of Bacilli and Bifidobacteriaceae (102 521 and 6235 CFU/ng DNA, respectively) (P < 0.0001). CONCLUSION: The commensal bacteria were decreased in fecal samples of participants with Crohn's disease when compared to the control group. There was no relation between the disease location and/or disease activity with the microbiota.

Gut microbiota of children with atopic dermatitis: Controlled study in the metropolitan region of São Paulo, Brazil.

BACKGROUND: It is possible that imbalances in the composition of the gut microbiota or the relationship of the microbiota with the host may be implicated in the origin of allergy. Therefore, we studied the intestinal microbiota of children with atopic dermatitis (AD). METHODS: Cross-sectional study with 81 children aged 5-11; 23 with AD and 58 controls. Surveys were conducted to obtain demographic, socioeconomic and neonatal data. Diagnosis of AD was made based on the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Eubacteria, Bacteroidetes, Firmicutes, B. fragilis, E. coli, Lactobacillus spp., S. aureus, E. faecalis, Salmonella spp., M. smithii, Bifidobacterium spp., C. difficile and C. perfringens were quantified using real-time PCR. RESULTS: The analysis showed an association between presence of C. difficile (OR: 5.88; 95 % CI: 1.24; 27.98), greater abundance of bifidobacteria (OR: 11.09; 95 % CI: 2.14; 57.39) and a lower abundance of lactobacilli (OR: 0.07; 95 % CI: 0.01; 0.51) in the gut microbiota of children with AD. Counts of Eubacteria (0,05×103 and 8.49×103), B. fragilis (0.72×109 and 4.5×109), Lactobacillus spp. (0.02×108 and 0.38×108), E. coli (0.13×109 and 1.52×109) and M. smithii (0.02×108 and 0.31×108) were lower in children with AD (P<0.05). CONCLUSIONS: This study confirmed that children living in the metropolitan area of São Paulo (Brazil) with AD have a different microbiota pattern with higher prevalence of C. difficile, lower abundance of Lactobacillus and greater abundance of bifidobacteria, regardless of socioeconomic status.

Randomized, Double-Blind, Placebo-Controlled Parallel Clinical Trial Assessing the Effect of Fructooligosaccharides in Infants with Constipation.

Constipation often begins in the first year of life. The aim of this study was to assess the effect of fructooligosaccharides (FOS) in the treatment of infants with constipation. This randomized, double-blind, placebo-controlled clinical trial included infants with constipation who were randomly assigned to one of two parallel groups: FOS or placebo. Either the FOS supplement or the placebo was added to the infant formula. Thirty-six infants completed the 4-week intervention. Therapeutic success occurred in 83.3% of the FOS group infants and in 55.6% of the control group infants (p = 0.073; one-tailed test). Compared with the control group, the FOS group exhibited a higher frequency of softer stools (p = 0.035) and fewer episodes of straining and/or difficulty passing stools (p = 0.041). At the end of the intervention, the mouth-to-anus transit time was shorter (22.4 and 24.5 h, p = 0.035), and the Bifidobacterium sp. count was higher (p = 0.006) in the FOS group. In conclusion, the use of FOS in infants with constipation was associated with significant improvement in symptoms, but the results showed no statistical significance regarding the success of the therapy compared with the control group. FOS was associated with reduced bowel transit time and higher counts of the genus Bifidobacterium in the stool.

Fecal microbiota analysis of children with small intestinal bacterial overgrowth among residents of an urban slum in Brazil / Análise da microbiota fecal de crianças com sobrecrescimento bacteriano no intestino delgado de moradoras de uma favela urbana no Brasil

Abstract Objective: To analyze the fecal microbiota composition of children living in an urban slum in Brazil, with or without small intestinal bacterial overgrowth, and to investigate the occurrence of stunting and anemia. Methods: A total of 100 children were studied, aged 5-11 years, from the municipality of Osasco, São Paulo. Small intestinal bacterial overgrowth was screened through hydrogen and methane breath test with lactulose. Weight and height were measured, and the height-for-age and body mass-for-age anthropometric indexes were calculated. The occurrence of anemia was investigated by capillary hemoglobin. Analysis of bacterial phylum, genus, and species was performed by real-time polymerase chain reaction in fecal samples. Results: Small intestinal bacterial overgrowth was identified in 61.0% of the children. A lower mean of height-for-age Z-score ([−0.48 ± 0.90] vs. [−0.11 ± 0.97]; p = 0.027), as well as capillary hemoglobin ([12.61 ± 1.03 g/dL] vs. [13.44 ± 1.19 g/dL]; p < 0.001) was demonstrated in children with SIBO when compared with children without small intestinal bacterial overgrowth. Children with small intestinal bacterial overgrowth presented a higher frequency of Salmonella spp., when compared to those without small intestinal bacterial overgrowth (37.7% vs. 10.3%; p = 0.002). Higher counts of total Eubacteria (p = 0.014) and Firmicutes (p = 0.038) were observed in children without small intestinal bacterial overgrowth; however, a higher count of Salmonella (p = 0.002) was found in children with small intestinal bacterial overgrowth. Conclusion: Children who lived in a slum and were diagnosed with small intestinal bacterial overgrowth showed lower H/A Z-scores and hemoglobin levels. Furthermore, differences were observed in the fecal microbiota of children with small intestinal bacterial overgrowth, when compared to those without it; specifically, a higher frequency and count of Salmonella, and lower counts of Firmicutes and total Eubacteria.

Resumo Objetivo: Analisar a composição da microbiota fecal de crianças moradoras de uma favela urbana no Brasil, com e sem sobrecrescimento bacteriano no intestino delgado, e investigar a ocorrência de déficit de crescimento e anemia. Métodos: Foram estudadas 100 crianças, com idade entre 5 e 11 anos, na cidade de Osasco, São Paulo. Sobrecrescimento bacteriano no intestino delgado foi pesquisado por teste respiratório do hidrogênio e metano no ar expirado com lactulose. Foram mensurados peso, estatura e calculados os índices antropométricos estatura para idade e índice de massa corporal para idade. Foi investigada a ocorrência de anemia, pela avaliação da hemoglobina capilar. A análise dos filos, gêneros e espécies bacterianas em amostras de fezes foi realizada por polymerase chain reaction em tempo real. Resultados: Sobrecrescimento bacteriano no intestino delgado foi diagnosticado em 61,0% das crianças avaliadas. Foi verificada menor média do escore Z do índice estatura para idade (-0,48±0,90 vs.-0,11±0,97 DP) e de hemoglobina capilar (12,61±1,03 vs. 13,44±1,19 g/dL) no grupo de crianças com sobrecrescimento bacteriano no intestino delgado, quando comparadas àquelas sem sobrecrescimento bacteriano no intestino delgado (p < 0,05). Nas crianças com sobrecrescimento bacteriano no intestino delgado foi observada maior frequência de Salmonella spp., quando comparadas àquelas sem sobrecrescimento bacteriano no intestino delgado (37,7% vs. 10,3%; p = 0,002). Maior contagem de Eubactérias totais (p = 0,014) e Firmicutes (p = 0,038) foi observada nas crianças sem sobrecrescimento bacteriano no intestino delgado, enquanto que as crianças com sobrecrescimento bacteriano no intestino delgado apresentaram maior contagem de Salmonella (p = 0,002). Conclusão: Nas crianças com diagnóstico de sobrecrescimento bacteriano no intestino delgado verificaram-se menores valores de estatura para idade e de hemoglobina. Foram constatadas diferenças na microbiota fecal das crianças com sobrecrescimento bacteriano no intestino delgado, especificamente, maior frequência e contagem de Salmonella spp. e menores contagens de Firmicutes e Eubactérias totais.

Children living near a sanitary landfill have increased breath methane and Methanobrevibacter smithii in their intestinal microbiota.

This study evaluated the breath CH4 excretion and concentration of M. smithii in intestinal microbiota of schoolchildren from 2 slums. One hundred and eleven children from a slum near a sanitary landfill, 35 children of a slum located away from the sanitary landfill, and 32 children from a high socioeconomic level school were included in the study. Real-time PCR was performed to quantify the M. smithii nifH gene and it was present in the microbiota of all the participating children, with higher (P < 0.05) concentrations in those who lived in the slum near the landfill (3.16 × 10(7) CFU/g of feces), comparing with the children from the slum away from the landfill (2.05 × 10(6) CFU/g of feces) and those from the high socioeconomic level group (3.93 × 10(5) CFU/g of feces). The prevalence of children who present breath methane was 53% in the slum near the landfill, 31% in the slum further away from the landfill and, 22% in the high socioeconomic level group. To live near a landfill is associated with higher concentrations of M. smithii in intestinal microbiota, comparing with those who live away from the landfill, regardless of their socioeconomics conditions.