Diarrhea in preschool children and Lactobacillus reuteri: a randomized controlled trial

Dietary Keratan Sulfate from Shark Cartilage Modulates Gut Microbiota and Increases the Abundance of Lactobacillus spp

Keratan sulfate (KS) represents an important family of glycosaminoglycans that are critical in diverse physiological processes. Recently, accumulating evidence has provided a wealth of information on the bioactivity of KS, which established it as an attractive candidate for drug development. However, although KS has been widely explored, less attention has been given to its effect on gut microbiota. Therefore, given that gut microbiota plays a pivotal role in health homeostasis and disease pathogenesis, we investigated here in detail the effect of KS on gut microbiota by high-throughput sequencing. As revealed by heatmap and principal component analysis, the mice gut microbiota was readily altered at different taxonomic levels by intake of low (8 mg/kg) and high dosage (40 mg/kg) of KS. Interestingly, KS exerted a differing effect on male and female microbiota. Specifically, KS induced a much more drastic increase in the abundance of Lactobacillus spp. in female (sixteen-fold) versus male mice (two-fold). In addition, combined with alterations in gut microbiota, KS also significantly reduced body weight while maintaining normal gut homeostasis. Altogether, we first demonstrated a sex-dependent effect of KS on gut microbiota and highlighted that it may be used as a novel prebiotic for disease management.

Probiotic administration among free-living older adults: a double blinded, randomized, placebo-controlled clinical trial

BACKGROUND

Diseases of the digestive system have been found to contribute to a higher symptom burden in older adults. Thus, therapeutic strategies able to treat gastrointestinal discomfort might impact the overall health status and help older adults to increase their overall health status and optimal functionality.

OBJECTIVE

The aim of this double-blinded, randomized, placebo-controlled clinical trial was to evaluate the effect of the probiotic strain Lactobacillus reuteri on digestive health and wellbeing in older adults.

METHODS

The study enrolled general older adults (>65 years). After eligibility screening qualified subjects (n = 290) participated in a 2-arm study design, with each arm consisting of 12 weeks of intervention of either active or placebo product. Primary outcome measure was set to changes in gastrointestinal symptoms and secondary outcome measures were changes in level of wellbeing, anxiety and stress. Follow up was performed at 8 and 12 weeks.

RESULTS

No persistent significant effects were observed on the primary or secondary outcome parameters of the study. A modest effect was observed in the probiotic arm, were levels of stress decreased at week 8 and 12. Similarly, we found that subjects suffering from indigestion and abdominal pain, respectively, showed a significant decrease of anxiety at week 8 after probiotic treatment, but not at week 12.

CONCLUSION

The RCT failed to show any improvement in digestive health after daily intake of a probiotic supplement containing L. reuteri. Neither was any significant improvement in wellbeing, stress or anxiety observed. Even though the RCT had a negative outcome, the study highlights issues important to take into consideration when designing trials among older adults.

TRIAL REGISTRATION

Clinicaltrials.gov/ NCT01837940 .

Systematic review with meta-analysis: Lactobacillus reuteri DSM 17938 for diarrhoeal diseases in children

BACKGROUND

Not all probiotics are equal.

AIM

To investigate the efficacy of Lactobacillus reuteri DSM 17938 (L. reuteri) in the management of various types of diarrhoeal diseases in children.

METHODS

Medline, Embase, the Cochrane Library, trial registries and reference lists of included studies were searched in January 2016, with no language restriction, for randomised controlled trials (RCTs).

RESULTS

Eight RCTs (n = 1229) met the inclusion criteria. In treatment trials, L. reuteri administration reduced the duration of diarrhoea (three RCTs, n = 256, mean difference, MD -24.82 h, 95% CI -38.8 to -10.8) and increased the cure rate on day 1 and day 2. However, heterogeneity and wide confidence intervals call for caution in interpreting results. In preventive trials carried out in hospitalised children, based on the findings from two RCTs (n = 290), there was no significant reduction in the risk of nosocomial diarrhoea, rotavirus diarrhoea or diarrhoea of any origin with L. reuteri administration. Based on one RCT (n = 97), there was no effect of L. reuteri on the risk of antibiotic-associated diarrhoea. However, the evidence is limited because the overall frequency of diarrhoea was surprisingly low. In preventive studies carried out in apparently healthy children, L. reuteri reduced diarrhoeal outcomes in one RCT; the evidence from another trial was less convincing.

CONCLUSIONS

In therapeutic settings, L. reuteri administration reduces the duration of diarrhoea and increases the chance of cure. In preventive settings, L. reuteri has the potential to reduce the risk of community-acquired diarrhoea in otherwise healthy children.

What are the indications for using probiotics in children?

The health benefits of probiotics have been the subject of extensive research. Still, some questions are being repeatedly asked: should one use or not use probiotics? If yes, how and when should probiotics be used? The purpose of this review is to summarise current evidence on specific probiotics' efficacy and safety to help healthcare professionals make evidence-based decisions on the indications for using specific probiotic strains or combinations in children. To identify relevant data, searches of MEDLINE and the Cochrane Library databases were performed in July 2015 to locate randomised controlled trials or their meta-analyses published in the last five years. The MEDLINE database also was searched for evidence-based clinical practice guidelines, developed by scientific societies. Considering that probiotics have strain-specific effects, the main focus was on data on individual probiotic strains, not on probiotics in general.

Safety and acceptability of Lactobacillus reuteri DSM 17938 and Bifidobacterium longum subspecies infantis 35624 in Bangladeshi infants: a phase I randomized clinical trial

BACKGROUND

Probiotics have rarely been studied in young healthy infants from low-income countries. This phase I study investigated the safety and acceptability of two probiotics in Bangladesh.

METHODS

Healthy infants aged four to twelve weeks from urban slums in Bangladesh were randomized to one of three different intervention dosing arms (daily, weekly, biweekly - once every two weeks) of Lactobacillus reuteri DSM 17938 and Bifidobacterium longum subspecies infantis 35624 over one month or to a fourth arm that received no probiotics. All subjects were followed for two additional months. Reported gastrointestinal and respiratory symptoms as well as breastfeeding rates, hospitalizations, differential withdrawals, and caretakers' perception of probiotic use were compared among arms.

RESULTS

In total, 160 infants were randomized (40 to each arm) with 137 (Daily n = 35, Weekly n = 35, Biweekly n = 35, Control n = 32) followed up for a median of twelve weeks; 113 completed the study. Illness and breastfeeding rates were similar across all arms. Ten hospitalizations unrelated to probiotic use occurred. Forty eight percent of the caretakers of infants in intervention arms believed that probiotics improved their baby's health.

CONCLUSIONS

These two commonly used probiotics appeared safe and well-accepted by Bangladeshi families.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01899378 . Registered July 10, 2013.

Effectiveness of Lactobacillus reuteri DSM 17938 for the Prevention of Nosocomial Diarrhea in Children: A Randomized, Double-blind, Placebo-controlled Trial

BACKGROUND

Multiple studies of probiotics used to prevent nosocomial diarrhea have provided conflicting results. The effects likely depend on the probiotic strain and/or dosage. The aim of this study was to assess the effectiveness of Lactobacillus reuteri DSM 17938 (L. reuteri; daily dose of 1 × 10 colony forming units) for preventing nosocomial diarrhea in children.

METHODS

We conducted a multicenter, randomized, double-blind, placebo-controlled trial in 184 children, 1-48 months of age, admitted to the hospital for reasons other than diarrhea. A computer-generated randomization scheme was used to allocate participants to receive either L. reuteri (n = 91) at a daily dose of 1 × 10 colony forming units, for the duration of hospitalization, or an identical appearing placebo (n = 93). Patients, study personnel and data analysts were blinded to assignment. The primary outcome was the occurrence of nosocomial diarrhea (≥3 loose or watery stools in 24 hours that occurred >72 hours after admission). Analysis was by intention-to-treat.

RESULTS

Baseline characteristics were similar in the 2 groups. Nosocomial diarrhea occurred in 13 (7.1%) children. No difference was found between the L. reuteri and the placebo groups (7/91 vs 6/93, respectively; relative risk: 1.19; 95% confidence interval: 0.43-3.27). There was also no difference between the L. reuteri and placebo groups for any of the secondary outcomes, including adverse effects. Rotavirus vaccination status had no effect on the results.

CONCLUSION

L. reuteri in the dosage regimen used was not effective in preventing nosocomial diarrhea in children.

Probiotics for Prevention and Treatment of Diarrhea

Probiotics are increasingly used for prevention and treatment of diarrhea more in children than in adults. Given the broad spectrum of diarrhea, this review focuses on the main etiologies: acute gastroenteritis, antibiotic-associated diarrhea (AAD), and necrotizing enterocolitis (NEC). For each, we reviewed randomized controlled trials, meta-analyses, and guidelines. For acute gastroenteritis we found 12 guidelines: 5 recommended probiotics and 7 did not. However, the guidelines containing positive recommendations provided proof of evidence from clinical trials and meta-analyses. Lactobacillus rhamnosus GG (LGG) and Saccharomyces boulardii had the most compelling evidence of efficacy as they reduced the duration of the disease by 1 day. For AAD 4 meta-analyses were found, reporting variable efficacy of probiotics in preventing diarrhea, based on the setting, patient's age, and antibiotics. The most effective strains were LGG and S. boulardii. For NEC, we found 3 randomized controlled trials, 5 meta-analyses, and 4 position papers. Probiotics reduced the risk of NEC enterocolitis and mortality in preterm babies. Guidelines did not support a routine use of probiotics and asked for further data for such sensitive implications. In conclusion, there is strong and solid proof of efficacy of probiotics as active treatment of gastroenteritis in addition to rehydration. There is solid evidence that probiotics have some efficacy in prevention of AAD, but the number needed to treat is an issue. For both etiologies LGG and S. boulardii have the strongest evidence. In NEC the indications are more debated, yet on the basis of available data and their implications, probiotics should be carefully considered.

Use of probiotics in pediatric infectious diseases

We summarize current evidence and recommendations for the use of probiotics in childhood infectious diseases. Probiotics may be of benefit in treating acute infectious diarrhea and reducing antibiotic-associated diarrhea. Potential benefits of probiotic on prevention of traveler's diarrhea,Clostridium difficile-associated diarrhea, side effects of triple therapy in Helicobacter pylori eradication, necrotizing enterocolitis, acute diarrhea, acute respiratory infections and recurrent urinary tract infections remain unclear. More studies are needed to investigate optimal strain, dosage, bioavailability of drops and tablets, duration of treatment and safety. Probiotics and recombinant probiotic strain represent a promising source of molecules for the development of novel anti-infectious therapy.

Gut Microbiome Composition in Young Nicaraguan Children During Diarrhea Episodes and Recovery

Understanding how the gut microbiota is affected by diarrhea episodes may help explain alterations in intestinal function among children in low-income settings. This study examined the composition of the gut microbiome of Nicaraguan children both during diarrhea episodes and while free of diarrhea for at least 2 months. Relative abundances of bacterial taxa, phylogenetic diversity, and species richness were determined by 16S amplicon sequencing and compared between paired diarrhea and recovery samples. A total of 66 stools were provided by 25 children enrolled in a 1-year cohort study of diarrhea etiologies. Children in our cohort had a mean age of 21.9 months; 64% were breast-fed, and 10% had received an antibiotic during the diarrhea episode. Overall, phylogenetic diversity and species richness did not differ significantly between diarrhea and recovery stools. However, of children who had a bacterial enteropathogen detected in any diarrhea stool, none experienced an increase in phylogenetic diversity in recovery, whereas of those in whom no bacterial enteropathogens were detected in their diarrhea stool(s), 59% experienced an increase in phylogenetic diversity in recovery (P = 0.008). This preliminary study suggests that recovery of the gut microbiota after a diarrhea episode may take longer time than previously thought and may be pathogen specific.

Lactobacillus reuteri DSM 17938 shortens acute infectious diarrhea in a pediatric outpatient setting

OBJECTIVE

Two randomized controlled clinical trials have shown that Lactobacillus (L) reuteri DSM 17938 reduces the duration of diarrhea in children hospitalized due to acute infectious diarrhea. This was the first trial evaluating the efficacy of L. reuteri DSM 17938 in outpatient children with acute infectious diarrhea.

METHODS

This was a multicenter, randomized, single-blinded, case control clinical trial in children with acute watery diarrhea. A total of 64 children who presented at outpatient clinics were enrolled. The probiotic group received 1×10(8)CFU L. reuteri DSM 17938 for five days in addition to oral rehydration solution (ORS) and the second group was treated with ORS only. The primary endpoint was the duration of diarrhea (in hours). The secondary endpoint was the number of children with diarrhea at each day of the five days of intervention. Adverse events were also recorded.

RESULTS

The mean duration of diarrhea was significantly reduced in the L. reuteri group compared to the control group (approximately 15h, 60.4±24.5h [95% CI: 51.0-69.7h] vs. 74.3±15.3h [95% CI: 68.7-79.9h], p<0.05). The percentage of children with diarrhea was lower in the L. reuteri group (13/29; 44.8%) after 48h than the control group (27/31; 87%; RR: 0.51; 95% CI: 0.34-0.79, p<0.01). From the 72nd hour of intervention onwards, there was no difference between the two groups in the percentage of children with diarrhea. No adverse effects related to L. reuteri were noted.

CONCLUSION

L. reuteri DSM 17938 is effective, safe, and well-tolerated in outpatient children with acute infectious diarrhea.

Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier

A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent–invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases.

Milk- and solid-feeding practices and daycare attendance are associated with differences in bacterial diversity, predominant communities, and metabolic and immune function of the infant gut microbiome

The development of the infant intestinal microbiome in response to dietary and other exposures may shape long-term metabolic and immune function. We examined differences in the community structure and function of the intestinal microbiome between four feeding groups, exclusively breastfed infants before introduction of solid foods (EBF), non-exclusively breastfed infants before introduction of solid foods (non-EBF), EBF infants after introduction of solid foods (EBF+S), and non-EBF infants after introduction of solid foods (non-EBF+S), and tested whether out-of-home daycare attendance was associated with differences in relative abundance of gut bacteria. Bacterial 16S rRNA amplicon sequencing was performed on 49 stool samples collected longitudinally from a cohort of 9 infants (5 male, 4 female). PICRUSt metabolic inference analysis was used to identify metabolic impacts of feeding practices on the infant gut microbiome. Sequencing data identified significant differences across groups defined by feeding and daycare attendance. Non-EBF and daycare-attending infants had higher diversity and species richness than EBF and non-daycare attending infants. The gut microbiome of EBF infants showed increased proportions of Bifidobacterium and lower abundance of Bacteroidetes and Clostridiales than non-EBF infants. PICRUSt analysis indicated that introduction of solid foods had a marginal impact on the microbiome of EBF infants (24 enzymes overrepresented in EBF+S infants). In contrast, over 200 bacterial gene categories were overrepresented in non-EBF+S compared to non-EBF infants including several bacterial methyl-accepting chemotaxis proteins (MCP) involved in signal transduction. The identified differences between EBF and non-EBF infants suggest that breast milk may provide the gut microbiome with a greater plasticity (despite having a lower phylogenetic diversity) that eases the transition into solid foods.

Probiotics for preventing acute upper respiratory tract infections

BACKGROUND

Probiotics may improve a person's health by regulating their immune function. Some trials have shown that probiotic strains can prevent respiratory infections. Even though the previous version of our review showed benefits of probiotics for acute upper respiratory tract infections (URTIs), several new studies have been published.

OBJECTIVES

To assess the effectiveness and safety of probiotics (any specified strain or dose), compared with placebo, in the prevention of acute URTIs in people of all ages, at risk of acute URTIs.

SEARCH METHODS

We searched CENTRAL (2014, Issue 6), MEDLINE (1950 to July week 3, 2014), EMBASE (1974 to July 2014), Web of Science (1900 to July 2014), the Chinese Biomedical Literature Database, which includes the China Biological Medicine Database (from 1978 to July 2014), the Chinese Medicine Popular Science Literature Database (from 2000 to July 2014) and the Masters Degree Dissertation of Beijing Union Medical College Database (from 1981 to July 2014). We also searched the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov for completed and ongoing trials on 31 July 2014.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing probiotics with placebo to prevent acute URTIs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and quality of trials, and extracted data using the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We included 13 RCTs, although we could only extract data to meta-analyse 12 trials, which involved 3720 participants including children, adults (aged around 40 years) and older people. We found that probiotics were better than placebo when measuring the number of participants experiencing episodes of acute URTI (at least one episode: odds ratio (OR) 0.53; 95% confidence interval (CI) 0.37 to 0.76, P value < 0.001, low quality evidence; at least three episodes: OR 0.53; 95% CI 0.36 to 0.80, P value = 0.002, low quality evidence); the mean duration of an episode of acute URTI (mean difference (MD) -1.89; 95% CI -2.03 to -1.75, P value < 0.001, low quality evidence); reduced antibiotic prescription rates for acute URTIs (OR 0.65; 95% CI 0.45 to 0.94, moderate quality evidence) and cold-related school absence (OR 0.10; 95% CI 0.02 to 0.47, very low quality evidence). Probiotics and placebo were similar when measuring the rate ratio of episodes of acute URTI (rate ratio 0.83; 95% CI 0.66 to 1.05, P value = 0.12, very low quality evidence) and adverse events (OR 0.88; 95% CI 0.65 to 1.19, P value = 0.40, low quality evidence). Side effects of probiotics were minor and gastrointestinal symptoms were the most common. We found that some subgroups had a high level of heterogeneity when we conducted pooled analyses and the evidence level was low or very low quality.

AUTHORS' CONCLUSIONS

Probiotics were better than placebo in reducing the number of participants experiencing episodes of acute URTI, the mean duration of an episode of acute URTI, antibiotic use and cold-related school absence. This indicates that probiotics may be more beneficial than placebo for preventing acute URTIs. However, the quality of the evidence was low or very low.

Informed consent in pediatric research

Pediatric drug research is gradually becoming more and more accepted as the norm for assessing whether a drug is safe and efficacious for infants and children. The process of informed consent and assent for these trials presents a major challenge. The aim of this review is to map historical, ethical and legal aspects relevant to the challenges of informed consent in the setting of pediatric drug research. The impact of age, level of maturity and life circumstances on the process of obtaining informed consent as well as the relations between consent and assent are discussed. There appears to be a lack of regulatory clarity in the area of pediatric clinical trials; while numerous statements have been made regarding children's rights to autonomy and their ability to care for themselves and for younger ones, the ever changing status of adolescence is still difficult to translate to informed consent. This may delay scientific and clinical advancement for children who are at the very junction of being independent and not needing parental permission. Obtaining consent and assent for pediatric clinical trials is a delicate matter, as both parent and child need to agree to participate. The appropriate transfer of information to guardians and the children, especially concerning potential risks and benefits, is at the heart of informed consent, as it serves to protect both patient and physician. As many adults lack health literacy, one must ensure that guardians receive relevant information at a level and in forms they can understand regarding the trials their children are asked to participate in.

Probiotics: an update

OBJECTIVE

Triggered by the growing knowledge on the link between the intestinal microbiome and human health, the interest in probiotics is ever increasing. The authors aimed to review the recent literature on probiotics, from definitions to clinical benefits, with emphasis on children.

SOURCES

Relevant literature from searches of PubMed, CINAHL, and recent consensus statements were reviewed.

SUMMARY OF THE FINDINGS

While a balanced microbiome is related to health, an imbalanced microbiome or dysbiosis is related to many health problems both within the gastro-intestinal tract, such as diarrhea and inflammatory bowel disease, and outside the gastro-intestinal tract such as obesity and allergy. In this context, a strict regulation of probiotics with health claims is urgent, because the vast majority of these products are commercialized as food (supplements), claiming health benefits that are often not substantiated with clinically relevant evidence. The major indications of probiotics are in the area of the prevention and treatment of gastro-intestinal related disorders, but more data has become available on extra-intestinal indications. At least two published randomized controlled trials with the commercialized probiotic product in the claimed indication are a minimal condition before a claim can be sustained. Today, Lactobacillus rhamnosus GG and Saccharomyces boulardii are the best-studied strains. Although adverse effects have sporadically been reported, these probiotics can be considered as safe.

CONCLUSIONS

Although regulation is improving, more stringent definitions are still required. Evidence of clinical benefit is accumulating, although still missing in many areas. Misuse and use of products that have not been validated constitute potential drawbacks.

The efficacy of Lactobacillus reuteri DSM 17938 in infants and children: a review of the current evidence

We aimed to systematically evaluate evidence on the effectiveness of Lactobacillus reuteri DSM 17938 (L. reuteri) for treating and preventing diseases in infants and children. MEDLINE and the Cochrane Library were searched in December 2013, with no language restrictions, for relevant randomized controlled trials (RCTs) and meta-analyses. The search was updated in April 2014. One systematic review and 14 RCTs met the inclusion criteria. The use of L. reuteri may be considered in the management of acute gastroenteritis as an adjunct to rehydration. There is some evidence that L. reuteri is effective in reducing the incidence of diarrhea in children attending day care centers. There is no evidence of effectiveness of L. reuteri in preventing nosocomial diarrhea in children. The administration of L. reuteri is likely to reduce crying time in infants with infantile colic in exclusively or predominantly exclusively breast-fed infants, but not in formula-fed infants. More studies are needed. Preliminary data suggest that L. reuteri may be effective in the prevention of some functional gastrointestinal disorders, such as colic and regurgitation. This innovative approach needs further evaluation by an independent research team. Preliminary evidence provides a rationale for further assessing the efficacy of L. reuteri for treating functional constipation or functional abdominal pain. However, it is too soon to recommend the routine use of L. reuteri for these conditions. There are no safety concerns with regard to the use of L. reuteri in nonimmunocompromised subjects. There are also data to support the safety of using L. reuteri in preterm infants.

CONCLUSION

Our results precisely define current evidence on the effects of the administration of L. reuteri DSM 17938 to the pediatric population.