Utilization of the Intestinal Tract as a Delivery System for Urogenital Probiotics Oral probiotics influence oral and respiratory tract infections in pediatric population: a randomized double-blinded placebo-controlled pilot study. Prebiotic and probiotic supplementation prevents rhinovirus infections in preterm infants: A randomized, placebo-controlled trial Use of probiotics in HIV-infected children: a randomized double-blind controlled study. Bifidobacterium animalis subsp. lactis BB-12 in reducing the risk of infections in early childhood Consumption of a Bifidobacterium bifidum Strain for 4 Weeks Modulates Dominant Intestinal Bacterial Taxa and Fecal Butyrate in Healthy Adults Efficacy of a polyvalent bacterial lysate in children with recurrent respiratory tract infections Probiotics Modulate Host-Microbe Interaction in the Placenta and Fetal Gut: A Randomized, Double-Blind, Placebo-Controlled Trial Probiotics and Prebiotics for the Prevention of Necrotizing Enterocolitis Lactobacillus plantarum 299v Does Not Reduce Enteric Bacteria or Bacterial Translocation in Patients Undergoing Colon Resection Disrupted Intestinal Microbiota and Intestinal Inflammation in Children with Cystic Fibrosis and Its Restoration with Lactobacillus GG: A Randomised Clinical Trial [Effects of probiotics on intestinal bacterial colonization in premature infants]. Three-Year Study of Viral Etiology and Features of Febrile Respiratory Tract Infections in Japanese Pediatric Outpatients Oral administration of two probiotic strains, Lactobacillus gasseri CECT5714 and Lactobacillus coryniformis CECT5711, enhances the intestinal function of healthy adults. Long-term safety of early consumption of Lactobacillus fermentum CECT5716: A 3-year follow-up of a randomized controlled trial. Effects of probiotic therapy in critically ill patients: a randomized, double-blind, placebo-controlled trial. Lactobacillus rhamnosus GG Intake Modifies Preschool Children’s Intestinal Microbiota, Alleviates Penicillin-Associated Changes, and Reduces Antibiotic Use [Effect of oral administration of probiotics on intestinal colonization with drug-resistant bacteria in preterm infants]. The Effect of Iranian Customary Used Probiotic Yogurt on the Children’s Salivary Cariogenic Microflora Low Serum 25-Hydroxyvitamin D Level and Risk of Upper Respiratory Tract Infection in Children and Adolescents Ingested probiotics reduce nasal colonization with pathogenic bacteria (Staphylococcus aureus, Streptococcus pneumoniae, and beta-hemolytic streptococci). Use of a polyvalent bacterial lysate in patients with recurrent respiratory tract infections: results of a prospective, placebo-controlled, randomized, double-blind study. Personalized Gut Mucosal Colonization Resistance to Empiric Probiotics Is Associated with Unique Host and Microbiome Features
Orally consumed viable bacteria with proposed beneficial health effects , the so-called probiotics , are increasingly used to treat disorders of the gastrointestinal tract . It has been recently suggested that specifically selected lactobacilli could have a therapeutic role in female urogenital tract infections . It has been also suggested that some of these bacteria could be not intravaginally instilled , but also orally delivered . The authors investigate the ability of lactobacilli isolated from the vagina to survive gastrointestinal tract transit , and establish a link between the rate of intestinal survival and vaginal colonization OBJECTIVE Acute oral and respiratory tract infections ( RTIs ) are highly present in the general population , and they represent one of the most impacting causes of morbidity and mortality every year . The aim of our study was to assess the clinical impact of oral probiotics on acute oral and respiratory tract infections affecting paediatric patients . PATIENTS AND METHODS This is a r and omized , double-blinded placebo-controlled clinical study , where probiotics have been compared with placebo in a double-blinded investigation . 40 subjects with a recent clinical history reporting oral and respiratory tract infections were r and omly selected and assigned to control ( n=20 ) or the probiotics ( n=20 ) group . During the 3 months before the starting , all subjects were assessed with several salivary examinations . RESULTS We found significant differences in the incidence of oral and respiratory tract infections between control and probiotic group , with a marked reduction of oral and respiratory tract infections episodes in the probiotic group . Salivary examinations gave similar results in both the groups , however , despite the salivary flow , viscosity and buffering were similar , on the contrary , pH values were found to be more alkaline in patients of probiotic group . CONCLUSIONS This study showed the main positive effects related to a supplementation with probiotics in order to prevent or reduce the incidence of infections onset in oral and respiratory tracts without any drugs-related adverse effects Background Simple and safe strategies for the prevention of viral respiratory tract infections ( RTIs )  are needed . Objective We hypothesized that early prebiotic or probiotic supplementation would reduce the risk of virus-associated RTIs during the first year of life in a cohort of preterm infants . Methods In this r and omized , double-blind , placebo-controlled trial ( Clinical Trials.gov no. NCT00167700 ) , 94 preterm infants ( gestational age , ≥32 + 0 and ≤36 + 6 weeks ; birth weight , > 1500 g ) treated at Turku University Hospital , Turku , Finl and , were allocated to receive oral prebiotics ( galacto-oligosaccharide and polydextrose mixture , 1:1 ) , a probiotic ( Lactobacillus rhamnosus GG , ATCC 53103 ) , or placebo ( microcrystalline cellulose ) between days 3 and 60 of life . The primary outcome was the incidence of clinical ly defined virus-associated RTI episodes confirmed from nasal swabs by using nucleic acid testing . Secondary outcomes were the severity and duration of RTIs . Results A significantly lower incidence of RTIs was detected in infants receiving prebiotics  ( rate ratio [ RR ] , 0.24 ; 95 % CI , 0.12 - 0.49 ; P < .001 ) or probiotics ( RR , 0.50 ; 95 % CI , 0.28 - 0.90 ; P = .022 ) compared with those receiving placebo . Also , the incidence of rhinovirus-induced episodes , which comprised 80 % of all RTI episodes , was found to be significantly lower in the prebiotic ( RR , 0.31 ; 95 % CI , 0.14 - 0.66 ; P = .003 ) and probiotic ( RR , 0.49 ; 95 % CI , 0.24 - 1.00 ; P = .051 ) groups compared with the placebo group . No differences emerged among the study groups in rhinovirus RNA load during infections , duration of rhinovirus RNA shedding , duration or severity of rhinovirus infections , or occurrence of rhinovirus RNA in asymptomatic infants . Conclusions Gut microbiota modification with specific prebiotics and probiotics might offer a novel and cost-effective means to reduce the risk of rhinovirus infections HIV/AIDS is an infection characterized by immune cell dysfunction and subsequent immunodeficiency , as well as intestinal disorder . Probiotics are live microbial feed supplements that beneficially affect the host animal by improving intestinal microbial balance and promoting health benefits . The goals of this study were to determine whether the use of probiotics could improve the immune response determined by CD4 cells mm(-3 ) counts and reduce liquid stool episodes . A r and omized double-blind controlled trial with 77 HIV-infected children ( 2 - 12 years ) , divided into two groups : one receiving probiotics ( formula containing Bifidobacterium bifidum with Streptococcus thermophilus -2.5 x 10(10 ) colony forming units ) and the other , a st and ard formula ( control group ) , for 2 months . The CD4 counts ( cells mm(-3 ) ) were collected at the beginning and end of the study . The quality and number of stools were assessed by a question naire ( watery to normal stool consistency ) . There was an increase in the mean CD4 count in the probiotics group ( 791 cells mm(-3 ) ) and a small decrease in the control group ( 538 cells mm(-3 ) ) . The change from baseline in mean CD4 cell count was + 118 cells mm(-3 ) vs. -42 cells mm(-3 ) for children receiving the probiotic formula and control formula , respectively ( p = 0.049 ) . A similar reduction in liquid stool consistency in both the groups ( p < 0.06 ) , with a slight enhancement in the probiotics group , was observed , but without significant difference ( p < 0.522 ) . The incidence of loose-soft stools showed a small decrease in both groups ( p < 0.955 ) and there was an increase in the incidence of normal stool consistency in both the groups ( p < 0.01 ) . Our study showed that probiotics have immunostimulatory properties and might be helpful in the treatment of HIV-infected children Background : Specific probiotic bacteria have proven to be effective in the prevention and treatment of infectious diseases in early life in at-risk population s. The impact of administration of Bifidobacterium animalis subsp . lactis BB-12 ( BB-12 ) on the risk of acute infectious diseases was studied in healthy children . Methods : In this double-blind , placebo-controlled study , 109 1-mo-old infants were assigned r and omly to a probiotic group receiving a BB-12–containing tablet ( n = 55 ) or a placebo ( n = 54 ) . Test tablets were administered to the infants twice a day ( daily dose of BB-12 10 billion colony-forming units ) until the age of 2 y with a novel slow-release pacifier or a spoon . Breastfeeding habits , pacifier use , dietary habits , medications , and all signs and symptoms of acute infections were registered in diaries by parents and in question naires by trained professionals . Results : The infants receiving BB-12 were reported to have experienced fewer respiratory tract infections ( RTIs ; 87 vs. 100 % ; risk ratio : 0.87 ; 95 % confidence interval : 0.76 , 1.00 ; P = 0.033 ) than the controls . No significant differences between the groups were observed in reported gastrointestinal symptoms , otitis media , or fever . The baseline characteristics of the two groups were similar , as was the duration of breastfeeding . Conclusion : Administration of BB-12 in early childhood may reduce RTIs ABSTRACT Modulation of the intestinal microbial ecosystem ( IME ) is a useful target to establish probiotic efficacy in a healthy population . We conducted a r and omized , double-blind , crossover , and placebo-controlled intervention study to determine the impact of Bifidobacterium bifidum strain Bb on the IME of adult healthy volunteers of both sexes .  High-throughput 16S rRNA gene sequencing was used to characterize the fecal microbiota before and after 4 weeks of daily probiotic cell consumption . The intake of approximately one billion live B. bifidum cells affected the relative abundance of dominant taxa in the fecal microbiota and modulated fecal butyrate levels . Specifically , Prevotellaceae ( P = 0.041 ) and Prevotella ( P = 0.034 ) were significantly decreased , whereas Ruminococcaceae ( P = 0.039 ) and Rikenellaceae ( P = 0.010 ) were significantly increased . We also observed that the probiotic intervention modulated the fecal concentrations of butyrate in a manner dependent on the initial levels of short-chain fatty acids ( SCFAs ) . In conclusion , our study demonstrates that a single daily administration of Bifidobacterium bifidum strain Bb can significantly modify the IME in healthy ( not diseased ) adults . These findings demonstrate the need to reassess the notion that probiotics do not influence the complex and stable IME of a healthy individual . IMPORTANCE Foods and supplements cl aim ed to contain health-promoting probiotic microorganisms are everywhere these days and mainly intended for consumption by healthy people . However , it is still debated what actual effects probiotic products may have on the healthy population . In this study , we report the results of an intervention trial aim ed at assessing the modifications induced in the intestinal microbial ecosystem of healthy adults from the consumption of a probiotic product . Our results demonstrate that the introduction of a probiotic product in the dietary habits of healthy people may significantly modify dominant taxa of the intestinal microbiota , result ing in the modulation of short-chain fatty acid concentrations in the gut . The overall changes witnessed in the probiotic intervention indicate a mechanism of microbiota modulation that could have potential effects on human health Respiratory tract infections ( RTIs ) are the most frequent infections in humans , particularly in children . In addition to intervention , increasing interest is focusing on immunomodulatory therapy for recurrent RTIs , which indicate a reduced defense capacity of the respiratory mucosa . LW 50020 , an oral immunomodulator that contains the antigens of seven bacteria common in RTIs , has reduced the number , duration , and severity of RTIs in children and adults . This 56-week placebocontrolled , double-blind study in 188 children investigated whether the efficacy of the st and ard schedule ( immunization cycle + one booster cycle ) would be enhanced by additional booster cycles . Efficacy and safety over the long term were also assessed . The rate of infection was reduced by 50 % with the st and ard schedule and could not be further decreased by two consecutive booster cycles . With both schedules , this reduction was sustained during a 28-week treatmentfree observation period that followed the 28-week treatment period . The number of adverse drug reactions was low , and all were transient , expected , and nonserious . These results confirm that LW 50020 is an effective and safe strategy for RTIs Background : Early host-microbe interaction provides important maturational stimuli for the developing immune system . The role of prenatal microbial contact remains elusive . Objectives : Our aim was to investigate whether microbes in placenta or amniotic fluid affect fetal innate immune gene expression during late pregnancy and whether innate immune gene expression profiles in the placenta and the fetal gut may be modulated by dietary supplementation with specific probiotics . Methods : Altogether 43 pregnant women were r and omized to receive ( 1 ) Bifidobacterium lactis , ( 2 ) B. lactis in combination with Lactobacillus rhamnosus GG ( LGG ) or ( 3 ) placebo for 14 days before elective cesarian section at full term in a double-blind clinical trial . Bacteria in amniotic fluid and placenta were detected by quantitative (q)PCR . The expression of Toll-like receptor (TLR)-related genes in the placenta and meconium sample s was assessed by qPCR . Gene expression patterns in meconium were interpreted to reflect immune physiology in the fetal gut . Results : The study was completed by 29 mother-infant pairs . Bacterial DNA was detected in all placenta sample s. Microbial DNA in amniotic fluid and placenta was associated with changes in TLR-related gene expression in the fetal intestine . Maternal probiotic supplementation significantly modulated the expression of TLR-related genes both in the placenta and in the fetal gut . Conclusions : Microbial contact in utero is associated with changes in fetal intestinal innate immune gene expression profile . Fetal and placental immune physiology may be modulated by maternal dietary intervention using specific probiotics Necrotizing enterocolitis ( NEC ) continues to be a major cause of morbidity and mortality in premature infants . Although the pathogenesis of NEC remains unclear , abnormal bacterial colonization has been postulated as playing a central role . Various factors impact bacterial colonization following delivery . Compared to term infants , the bacterial colonization pattern in prematurely born infants is markedly different , with a greater predilection for colonization with pathogenic bacteria . Probiotic and prebiotic administration offers the opportunity to manipulate the intestinal bacterial environment , favoring the growth of commensal bacteria . Experimental data from animal studies and data from human trials suggest that probiotics decrease the incidence of NEC . These preliminary studies support the need for a large , r and omized , controlled trial to further investigate the role of probiotics in the prevention of NEC Background Probiotics may exert beneficial effects in the gastrointestinal tract . This r and omized trial investigated the effect of the probiotic Lactobacillus plantarum 299v on the intestinal load of potentially pathogenic bacteria , bacterial translocation , and cell proliferation in elective colon surgery . Methods Seventy-five patients were r and omized to pre- and postoperative oral intake of Lactobacillus plantarum 299v or placebo .  Rectal swabs and mucosal biopsies were taken before the start of intake , after 1 week , at surgery , and after 6 days , weeks , and months . Viable counts were quantified for clostridia , Enterobacteriaceae , Gram-negative anaerobes , and lactobacilli . Bacterial translocation was determined by the analysis of bacterial DNA genes in mesenteric lymph nodes . Ki-67 was used as a marker of cell proliferation in normal mucosa and tumor . Results Lactobacillus plantarum 299v was given without adverse effects . Lactobacillus plantarum 299v as well as Enterobacteriaceae and Gram-negative anaerobes increased in the colon 1 week after the administration of Lactobacillus plantarum 299v . There were no significant differences between patients receiving Lactobacillus plantarum 299v and placebo in the incidence of bacterial translocation ( 27 vs. 13 % ) and postoperative complications ( 16 vs. 31 % ) . Conclusions Lactobacillus plantarum 299v was established in the intestine , but no inhibitory effect on enteric bacteria , bacterial translocation , or postoperative complications was found . The mechanism behind the protective effects of probiotics found in animal and some human studies remain elusive and require further explorations . No adverse effects were recorded after the administration of high doses of Lactobacillus plantarum 299v Background & Aims Intestinal inflammation is a hallmark of cystic fibrosis ( CF ) . Administration of probiotics can reduce intestinal inflammation and the incidence of pulmonary exacerbations . We investigated the composition of intestinal microbiota in children with CF and analyzed its relationship with intestinal inflammation . We also investigated the microflora structure before and after Lactobacillus GG ( LGG ) administration in children with CF with and without antibiotic treatment .  Methods The intestinal microbiota were analyzed by denaturing gradient gel electrophoresis ( DGGE ) , real-time polymerase chain reaction ( RT-PCR ) , and fluorescence in situ hybridization ( FISH ) . Intestinal inflammation was assessed by measuring fecal calprotectin ( CLP ) and rectal nitric oxide ( rNO ) production in children with CF as compared with healthy controls . We then carried out a small double-blind r and omized clinical trial with LGG . Results Twenty-two children with CF children were enrolled in the study ( median age , 7 years ; range , 2–9 years ) . Fecal CLP and rNO levels were higher in children with CF than in healthy controls ( 184±146 µg/g vs. 52±46 µg/g ; 18±15 vs. 2.6±1.2 µmol/L NO2 − , respectively ; P<0.01 ) . Compared with healthy controls , children with CF had significantly different intestinal microbial core structures . The levels of Eubacterium rectale , Bacteroides uniformis , Bacteroides vulgatus , Bifidobacterium adolescentis , Bifidobacterium catenulatum , and Faecalibacterium prausnitzii were reduced in children with CF . A similar but more extreme pattern was observed in children with CF who were  taking antibiotics . LGG administration reduced fecal CLP and partially restored intestinal microbiota . There was a significant correlation between reduced microbial richness and intestinal inflammation . Conclusions CF causes qualitative and quantitative changes in intestinal microbiota , which may represent a novel therapeutic target in the treatment of CF . Administration of probiotics restored gut microbiota , supporting the efficacy of probiotics in reducing intestinal inflammation and pulmonary exacerbations . Trial Registration Clinical Trials.gov NCT OBJECTIVE To study the possible roles of probiotics in decreasing intestinal bacterial colonization rate and the incidence of enterogenic infections in premature infants . METHODS Seventy premature infants were r and omly assigned to two groups : probiotics and conventional treatment groups ( control ) ( n=35 each ) . The probiotics treatment group was administered with oral Clostridium butyricum powder ( 250 mg , twice daily up to discharge ) 24 hrs after birth except conventional treatment .  Rectal swab cultures were done at admission , 5 and 12 days after admission , and before discharge . Clinical and laboratory findings were compared between the two groups . RESULTS The intestinal bacterial colonization rate in the probiotics treatment group was lower than that in the control group 12 days after admission ( 60 % vs 83 % ; p<0.05 ) and before discharge ( 51 % vs 80 % ; p<0.05 ) . Klebsiella pneumoniae , Escherichia coli and Enterococcus faecium were common colonization bacteria in the two groups . Diarrhea occurred in 7 cases ( 20 % ) in the probiotics treatment group compared with 16 cases ( 46 % ) in the control group ( p<0.05 ) . Two infants ( 6 % ) developed sepsis in the probiotics treatment group compared with 9 cases ( 26 % ) in the control group ( p<0.05 ) . CONCLUSIONS Probiotics can decrease intestinal bacterial colonization rate and the incidence of diarrhea and sepsis in premature infants Background : For most febrile respiratory tract infections ( RTIs ) in children , the causative pathogen is never identified . We sought to identify the causative pathogen in individual cases of pediatric outpatient with RTIs and to determine whether particular clinical features of RTIs are associated with particular viruses . Methods : Over 3 years , we prospect ively collected nasopharyngeal aspirate specimens from individual pediatric out patients with an RTI accompanied by persistent fever ( > 3 days , ≥38.0 ° C ) and peak temperature ≥39.0 ° C . Two methods —(1 ) viral culture for respiratory viruses and ( 2 ) real-time polymerase chain reaction ( PCR ) assays identifying 9 different respiratory viruses and 2 respiratory bacteria — were used to test specimens . Results : For 495 specimens , viral culture and real-time PCR assays together identified at least 1 pathogen in 83.0 % and ≥1 viruses alone in 79.4 % . These 2 methods identified 138 children with respiratory syncytial virus , 66 with human metapneumovirus , 73 with parainfluenza viruses , 124 with adenovirus , 23 with rhinovirus , 38 with enterovirus , 11 with influenza type C virus , 15 with Mycoplasma pneumoniae and 3 with Chlamydophila pneumoniae ; the coinfection rate was 19.7 % among all infections . Among the patients with single-pathogen infections , the rate of lower RTI was 37.6 % for respiratory syncytial virus , 40.7 % for human metapneumovirus , 18.2 % for parainfluenza viruses and 2.2 % for adenovirus ( P < 0.01 ) . Conclusions : Viral culture and real-time PCR assays were used together to identify causative pathogens in 83 % of febrile outpatient children with RTI ; specific viruses were associated with particular clinical diagnoses Modifications in gastrointestinal parameters , intestinal colonization and tolerance are some of the main goals cl aim ed for probiotics . However , although healthy people are the common target for these new functional food products , the number of clinical trials analysing the effects of probiotics in gastrointestinal parameters of healthy subjects is very scarce . A r and omized , double blind , placebo-controlled human clinical trial involving 30 healthy adults was performed to investigate the effect of a fermented product containing two probiotic strains , Lactobacillus gasseri CECT5714 and Lactobacillus coryniformis CECT5711 , on several blood and fecal parameters , most of them related to the host intestinal function . The volunteers were r and omly distributed into two groups , one receiving a st and ard yogurt and the other a similar dairy fermented product in which the Lactobacillus delbreuckii subsp . bulgaricus yogurt strain had been replaced by a combination of the probiotic strains L. gasseri CECT5714 and L. coryniformis CECT5711 . The volunteers that received the probiotic strains reported no adverse effects and the strains could be isolated from their feces at a relatively high level . In fact , the concentration of fecal lactic acid bacteria significantly increased in the probiotic group . Additionally , the oral administration of the probiotic strains led to an improvement of parameters such as the production of short chain fatty acids , the fecal moisture and the frequency and volume of the stools . As a result , the volunteers assigned to the probiotic group perceived a clear improvement in their intestinal habits . The study revealed that probiotics may exert a positive effect on healthy adults Lactobacillus fermentum CECT5716 is a probiotic strain originally isolated from human breast milk . Previous clinical studies in infants showed that the early administration of a milk formula containing this probiotic strain was safe and may be useful for the prevention of community-acquired infections . This is a 3-year follow-up study aim ed at evaluating the long-term effects produced by the early consumption of an infant formula supplemented with L. fermentum CECT5716 ( experimental group , EG ) compared with a control formula without the probiotic ( control group , CG ) . The infants included in this follow-up study had previously completed a 5-month r and omized double-blind controlled trial ( from 1 to 6 months of age ) , where the safety and tolerance of the probiotic formula was evaluated . The main outcome of the follow-up study was the growth of the children . The secondary outcomes included the incidence of infectious and non-infectious diseases , parameters related with intestinal function and faecal microbiota . At 3 years , the mean values of weight , length and head circumference were similar in children of the EG compared with those of the CG . No differences were observed in the incidence of infectious and non-infectious diseases or disorders related with intestinal function . The pattern of faecal microbiota was also similar between both groups . In conclusion , this 3-year study shows that the early administration of the probiotic of L. fermentum CECT5716 in an infant formula is safe and it does not produce measurable differences in children compared with a control formula BACKGROUND Multiple organ dysfunction syndrome ( MODS ) is a major cause of mortality in intensive care units . A breakdown in gut barrier function and immune dysfunction are associated with the onset of MODS . Probiotic bacteria have been shown to modulate intestinal barrier and immune function . OBJECTIVE This study assessed the efficacy of a probiotic compound in a viable and nonviable formulation in modulating intestinal permeability and immune function and preventing the onset of MODS in patients in the intensive care unit . DESIGN A double-blind , r and omized controlled trial was conducted in the intensive care unit of a tertiary care teaching hospital . Twenty-eight critically ill patients admitted to the intensive care unit were r and omly assigned to receive 1 of 3 treatments daily for 7 d : 1 ) placebo , 2 ) viable probiotics , or 3 ) equivalent probiotic sonicates .  MODS scores and systemic concentrations of immunoglobulin ( Ig ) A and IgG were measured on days -1 , 4 , and 7 , and intestinal permeability measurements were taken daily . RESULTS The patients responded to viable probiotics with a significantly larger increase in systemic IgA and IgG concentrations than in the patients who received placebo or sonicates ( P < 0.05 ) . MODS scores were not significantly affected by probiotic treatment . Over the study period , intestinal permeability decreased in most patients . CONCLUSION Patients receiving viable probiotics show a greater enhancement in immune activity than do patients receiving either placebo or probiotic bacterial sonicates Antibiotic use is considered among the most severe causes of disturbance to children ’s developing intestinal microbiota , and frequently causes adverse gastrointestinal effects ranging from mild and transient diarrhoea to life-threatening infections . Probiotics are commonly advocated to help in preventing antibiotic-associated gastrointestinal symptoms . However , it is currently unknown whether probiotics alleviate the antibiotic-associated changes in children ’s microbiota . Furthermore , it is not known how long-term probiotic consumption influences the developing microbiota of children . We analysed the influence of long-term Lactobacillus rhamnosus GG intake on preschool children ’s antibiotic use , and antibiotic-associated gastrointestinal complaints in a double blind , r and omized placebo-controlled trial with 231 children aged 2–7 . In addition , we analysed the effect of L. rhanmosus GG on the intestinal microbiota in a subset of 88 children . The results show that long-term L. rhamnosus GG supplementation has an influence on the composition of the intestinal microbiota in children , causing an increase in the abundance of Prevotella , Lactococcus , and Ruminococcus , and a decrease in Escherichia . The treatment appeared to prevent some of the changes in the microbiota associated with penicillin use , but not those associated with macrolide use . The treatment , however , did reduce the frequency of gastrointestinal complaints after a macrolide course . Finally , the treatment appeared to prevent certain bacterial infections for up to 3 years after the trial , as indicated by reduced antibiotic use . Trial Registration : Clinical Trials.gov OBJECTIVE To evaluate the effect of oral administration of probiotics on intestinal colonization with drug-resistant bacteria among preterm infants in the neonatal intensive care unit ( NICU ) . METHODS A double-blind , r and omized , placebo-controlled trial was carried out in the preterm infants who were transferred to the NICU immediately after birth . These infants were stratified by whether they were breastfed and then r and omized into test group and control group . The test group was given probiotics from the day when enteral feeding began , while the control group was treated conventionally without probiotics . The two groups were compared in terms of the colonization with extended-spectrum beta-lactamase-producing bacteria , as assessed by rectal swabs on days 1 , 3 , 7 , and 14 after birth , and the incidence of diseases . RESULTS Rectal colonization with drug-resistant bacteria was found in the test group ( n=119 ) and control group ( n=138 ) on days 1 , 3 , 7 , and 14 after birth . There were no significant differences in the incidence of late-onset sepsis and necrotizing enterocolitis between the two groups ( P>0.05 ) . Among non-breastfed infants , the test group had significantly decreased rectal colonization with drug-resistant bacteria compared with the control group on day 14 after birth ( 71.1 % vs 88.9 % ; P=0.04 ) . No probiotic-related adverse events were observed in the study . CONCLUSIONS Oral administration of probiotics may reduce rectal colonization with drug-resistant bacteria in preterm infants under certain conditions and shows good safety Statement of the Problem Dental caries is the most common disease of childhood . Using probiotics has recently been introduced to reduce the incidence of dental caries . It consists of live microbial food supplements that beneficially affect the host , and hence are considered an alternative way to eradicate the infections . Purpose The aim of this study is to evaluate the effect of consumption of probiotic yogurt on the children ’s salivary cariogenic microflora .  Material s and Method A double-blind r and omized study was performed recruiting 2 parallel groups ; 24 healthy children in the case and 25 children in the control group . All healthy children were followed- up over 4 periods . Periods 1 and 3 were wash-out periods with duration of 1 and 2 weeks , respectively . During periods 2 and 4 ( 2weeks duration each ) , the case group consumed 200 g yogurt containing Bifidobacterium lactis ( 1 × 106 per gram ) once daily and the control group consumed normal yogurt .  Salivary Streptococci mutans and Lactobacilli were enumerated before and after the yogurt consumption periods . Pre- and post-treatment values within and between regimens were compared using the t-test and paired sample s. Results There was a reduction in Streptococcus mutans and Lactobacillus counts in the control group , but for Streptococcus mutans , the count reduction between phases 1 and 4 was statistically significant ( p= 0.009 ) . In the case group , neither the Streptococcus mutans count nor the Lactobacilli count was significantly reduced . Conclusion Based on the findings of this study , short-term daily consumption of probiotic yogurt containing Bifidobacterium lactis could not reduce the levels of salivary Streptococcus mutans and Lactobacilli in 6 to 12 year-old children , while normal yogurt could reduce the Streptococcus mutans counts significantly Respiratory tract infections ( RTIs ) are very common worldwide . We prospect ively demonstrate an association between low serum 25-hydroxyvitamin D level and increased risk of laboratory-confirmed viral upper RTI  in children . Future studies should evaluate the role of supplementation to reduce RTIs BACKGROUND As a bacterial reservoir , the nose may harbor potentially pathogenic bacteria ( PPB : Staphylococcus aureus , Streptococcus pneumoniae , beta-hemolytic streptococci , and Haemophilus influenzae ) . In patients carrying PPB , antiseptic regimens could be crucial for infection control after major operations on or injuries of the head , nasal sinuses , or lungs . Such regimens may also be important for diabetic patients and persons receiving hemodialysis , in intensive care units , or with impaired immunity due to various other causes . OBJECTIVE We tested a possible effect of the ingestion of probiotics on the bacterial flora of the nose . DESIGN In an open , prospect i ve trial , 209 volunteers were r and omly assigned to consume either a probiotic , fermented milk drink [ 65 mL with Lactobacillus GG ( ATCC 53103 ) , Bifidobacterium sp B420 , Lactobacillus acidophilus 145 , and Streptococcus thermophilus ; n = 108 ] or st and ard yogurt ( 180 g ; n = 101 ) daily for 3 wk . Nasal microbial flora were analyzed on days 1 , 21 , and 28 . The microbial examination was blinded to the source of the sample s. RESULTS We found a significant reduction ( 19 % ; P < 0.001 ) in the occurrence of nasal PPB in the group who consumed the probiotic drink but not in the group who consumed yogurt . The effect was mainly on gram-positive bacteria , which decreased significantly ( P < 0.05 ) . CONCLUSIONS The results indicate that regular intake of probiotics can reduce PPB in the upper respiratory tract . The results also indicate a linkage of the lymphoid tissue between the gut and the upper respiratory tract Respiratory tract infections ( RTIs ) are the most common infections in humans , and it is difficult to effectively treat patients with increased susceptibility to these ailments . LW 50020 ( Luivac ; Paspat oral ) , an oral immunomodulator consisting of the antigens of seven bacteria commonly involved in RTIs , has been developed for the induction of specific and nonspecific immune responses of the mucosa-associated lymphoid tissue . In this placebo-controlled study , the efficacy and safety of the tablet formulation of LW 50020 were evaluated in children and adults with recurrent RTIs . Tablets were taken once daily during two periods of 4 weeks each , interrupted by a treatment-free interval of 4 weeks . The main endpoint of the study , a clinical severity score that evaluated treatment benefits , was significantly lower in the second study period in patients treated with the bacterial lysate compared to patients given placebo . A comparison of the infection rates in the first and second study periods of patients treated with LW 50020 revealed a placebo-corrected reduction of 39 % in children and a placebo-corrected reduction of 44 % in adolescents and adults . The placebo-corrected duration of infections was shortened by 47 % in children and by 55 % in older patients . No serious drug-related side effects occurred . This study demonstrated that the oral bacterial immunomodulator LW 50020 is efficacious in treating patients with recurrent RTIs Empiric probiotics are commonly consumed by healthy individuals as means of life quality improvement and disease prevention . However , evidence of probiotic gut mucosal colonization efficacy remains sparse and controversial . We metagenomically characterized the murine and human mucosal-associated gastrointestinal microbiome and found it to only partially correlate with stool microbiome . A sequential invasive multi-omics measurement at baseline and during consumption of an 11-strain probiotic combination or placebo demonstrated that probiotics remain viable upon gastrointestinal passage . In colonized , but not germ-free mice , probiotics encountered a marked mucosal colonization resistance . In contrast , humans featured person- , region- and strain-specific mucosal colonization patterns , hallmarked by predictive baseline host and microbiome features , but indistinguishable by probiotics presence in stool . Consequently , probiotics induced a transient , individualized impact on mucosal community structure and gut transcriptome . Collectively , empiric probiotics supplementation may be limited in universally and persistently impacting the gut mucosa , meriting development of new personalized probiotic approaches
Conclusion : Based on the available data and taking into account the safety profile of RCTs , probiotic consumption appears to be a feasible way to decrease the incidence of RTIs in children
Background : Respiratory tract infections ( RTIs ) represent one of the main health problems in children .
Probiotics are viable bacteria that colonize the intestine and affect the host intestinal microbial balance .
Accumulating evidence suggests that probiotic consumption may decrease the incidence of or modify RTIs .
The authors systematic ally review ed data from r and omized controlled trials ( RCTs ) to investigate the effect of probiotic consumption on  RTIs in children .