The Proportion of Bifidobacterium and Escherichia coli in Colon of Children with Recurrent Urinary Tract Infection.

Recurrent urinary tract infection (UTI) in children is a well-known risk factor of chronic kidney disease. Periurethral area is normally inhabited by non-pathogenic flora, such as Bifidobacterium sp., and pathogenic flora from gastrointestinal tract, such as Escherichia coli (E. coli), which can cause UTI. Dysbiosis between pathogenic and non-pathogenic bacteria leads to infections, but studies regarding dysbiosis and recurrent UTI have not yet been documented. To estimate the proportional differences between gastrointestinal E. coli and Bifidobacterium sp. in children with recurrent UTI, a cross-sectional study was conducted in children from age six months to <18 years old diagnosed with recurrent UTI in Dr. Cipto Mangunkusumo Hospital. Healthy children matched in gender and age were recruited as control group. Stool samples were obtained from all the children in the two groups. Stool DNA was extracted using real-time polymerized chain reaction method to count E. coli and Bifidobacterium sp. proportion. Children with recurrent UTI had significantly higher proportion of E. coli compared to control group (10.97 vs. 4.74; P = 0.014) and lower proportion of Bifidobacterium sp. (6.54 vs. 9.33; P = 0.594). In children with recurrent UTI group, E. coli proportion was found higher than Bifidobacterium sp. although not statistically significant (10.97 vs. 6.54; P = 0.819). In healthy controls, Bifidobacterium sp. proportion was significantly higher than E. coli (4.74 vs. 9.33; P = 0.021). The total amount of E. coli (996,004 vs. 1,099,271; P = 0.798) and Bifidobacterium sp. (835,921 vs. 1,196,991; P = 0.711) were higher in secondary UTI compared to the simple UTI. Proportion of E. coli is higher in children with recurrent UTI than in healthy children. The proportion of E. coli is higher than Bifidobacterium sp in the colon of children with recurrent UTI.

Bifidobacterium Abundance in Early Infancy and Vaccine Response at 2 Years of Age.

BACKGROUND: The intestinal microbiome in early infancy affects immunologic development and thus may affect vaccine memory, though few prospective studies have examined such associations. We examined the association of Bifidobacterium levels in early infancy with memory responses to early vaccination measured at 2 years of age. METHODS: In this prospective observational study, we examined the association of Bifidobacterium abundance in the stool of healthy infants at 6 to 15 weeks of age, near the time of vaccination, with T-cell and antibody responses measured at 6 weeks, 15 weeks, and 2 years of age. Infants were vaccinated with Bacillus Calmette-Guérin (BCG) (at birth), oral polio virus (at birth and at 6, 10, and 14 weeks), tetanus toxoid (TT) (at 6, 10, and 14 weeks), and hepatitis B virus (at 6, 10, and 14 weeks). Fecal Bifidobacterium was measured at 6, 11, and 15 weeks. Bifidobacterium species and subspecies were measured at 6 weeks. RESULTS: Mean Bifidobacterium abundance in early infancy was positively associated with the CD4 T-cell responses to BCG, TT, and hepatitis B virus at 15 weeks, with CD4 responses to BCG and TT at 2 years, and with plasma TT-specific immunoglobulin G and stool polio-specific immunoglobulin A at 2 years. Similar associations were seen for the predominant subspecies, Bifidobacterium longum subspecies infantis. CONCLUSIONS: Bifidobacterium abundance in early infancy may increase protective efficacy of vaccines by enhancing immunologic memory. This hypothesis could be tested in clinical trials of interventions to optimize Bifidobacterium abundance in appropriate populations.

Site and clinical significance of Alloscardovia omnicolens and Bifidobacterium species isolated in the clinical laboratory.

Most of the members of the genus Bifidobacterium, including the related organism Alloscardovia omnicolens, are inhabitants of the gastrointestinal tract and oral cavity of humans and animals and have been considered nonpathogenic for humans. However, the actual site of isolation and the clinical significance of A. omnicolens and of Bifidobacterium species are unclear. This may be due in part to the difficulties in distinguishing these organisms from other genera such as Actinomyces. To determine the potential disease-causing role of these organisms, we analyzed the clinical significance of 15 A. omnicolens and Bifidobacterium isolates identified by 16S rRNA gene sequencing from a clinical laboratory. All of the organisms in this study were isolated from sterile sites or in significant numbers by standard clinical microbiological culture methods. Our 15 clinical strains fit into only four species: A. omnicolens (five isolates), Bifidobacterium scardovii (four isolates), B. longum (two isolates), and B. breve (four isolates). All five A. omnicolens isolates, one of the B. breve isolates, and three of the four B. scardovii isolates were cultured from urine at 10(5) CFU/ml. One B. scardovii isolate was from a patient with a genitourinary tract wound infection, two B. longum isolates were from abdominal wounds, and three B. breve isolates were from blood cultures. This study enlarges the spectrum of diseases and clinical sources associated with A. omnicolens and Bifidobacterium species and addresses identification problems.

Bifidobacterial species differentially affect expression of cell surface markers and cytokines of dendritic cells harvested from cord blood.

The gut microbiota may be important in the postnatal development of the immune system and hence may influence the prevalence of atopic diseases. Bifidobacteria are the most numerous bacteria in the guts of infants, and the presence or absence of certain species could be important in determining the geographic incidence of atopic diseases. We compared the fecal populations of bifidobacteria from children aged 25 to 35 days in Ghana (which has a low prevalence of atopy), New Zealand, and the United Kingdom (high-prevalence countries). Natal origin influenced the detection of bifidobacterial species in that fecal samples from Ghana almost all contained Bifidobacterium infantis whereas those of the other children did not. Choosing species on the basis of our bacteriological results, we tested bifidobacterial preparations for their effects on cell surface markers and cytokine production by dendritic cells harvested from cord blood. Species-specific effects on the expression of the dendritic-cell activation marker CD83 and the production of interleukin-10 (IL-10) were observed. Whereas CD83 expression was increased and IL-10 production was induced by Bifidobacterium bifidum, Bifidobacterium longum, and Bifidobacterium pseudocatenulatum, B. infantis failed to produce these effects. We concluded that B. infantis does not trigger the activation of dendritic cells to the degree necessary to initiate an immune response but that B. bifidum, B. longum, and B. pseudocatenulatum induce a Th2-driven immune response. A hypothesis is presented to link our observations to the prevalence of atopic diseases in different countries.

Risk factors of development of gut-derived bacterial translocation in thermally injured rats.

AIM: Studies have demonstrated that gut-derived bacterial translocation (BT) might play a role in the occurrence of sepsis and multiple organ dysfunction syndrome (MODS). Yet, no convincing overall analysis of risk factors for BT has been reported. The purpose of this study was to evaluate the related factors for the development of BT in burned rats. METHODS: Wistar rats were subjected to 30% third-degree burns. Then samples were taken on postburn d 1, 3, and 5. Incidence of BT and counts of mucosal bifidobacteria, fungi and E. coli, mucus sIgA, degree of injury to ileal mucosa, and plasma interleukin-6 were observed. Univariate analysis and multivariate logistic regression analysis were performed. RESULTS: The overall BT rate was 53.9% (69 in 128). The result of univariate analysis showed that the levels of plasma endotoxin and interleukin-6, the counts of mucosal fungi and E. coli, and the scores of ileum lesion were markedly increased in animals with BT compared with those without (P=0.000-0.005), while the levels of mucus sIgA and the counts of mucosal bifidobacteria were significantly reduced in animals with translocation compared with those without (P=0.000). There was a significant positive correlation between mucus sIgA and the counts of mucosal bifidobacteria (r=0.74, P=0.001). Moreover, there were strong negative correlations between scores of ileum-lesion and counts of bifidobacteria (r=-0.67, P=0.001). Multivariate logistic regression revealed that ileum lesion score (odds ratio [OR] 45.52, 95% confidence interval [CI] 5.25-394.80), and counts of mucosal bifidobacteria (OR 0.039, 95% CI 0.0032-0.48) were independent predictors of BT secondary to severe burns. CONCLUSION: Ileal lesion score and counts of mucosal bifidobacteria can be chosen as independent prognosis factors of the development of BT. Specific interventions targeting these high-risk factors might be implemented to attenuate BT, including strategies for repair of damaged intestinal mucosae and restoration of the balance of gastrointestinal flora.