Background:As a non-invasive and effective diagnostic method for small intestinal bacterial overgrowth(SIBO),wild-use of breath test(BT)has demonstrated a high comorbidity rate in patients with diarrhea-predominant ir...Background:As a non-invasive and effective diagnostic method for small intestinal bacterial overgrowth(SIBO),wild-use of breath test(BT)has demonstrated a high comorbidity rate in patients with diarrhea-predominant irritable bowel syndrome(IBS-D)and SIBO.Patients overlapping with SIBO respond better to rifaximin therapy than those with IBS-D only.Gut microbiota plays a critical role in both of these two diseases.We aimed to determine the microbial difference between IBS-D overlapping with/without SIBO,and to study the underlying mechanism of its sensitivity to rifaximin.Methods:Patients with IBS-D were categorized as BT-negative(IBSN)and BT-positive(IBSP).Healthy volunteers(BT-negative)were enrolled as healthy control.The patients were clinically evaluated before and after rifaximin treatment(0.4 g bid,4 weeks).Blood,intestine,and stool samples were collected for cytokine assessment and gut microbial analyses.Results:Clinical complaints and microbial abundance were significantly higher in IBSP than in IBSN.In contrast,severe systemic inflammation and more active bacterial invasion function that were associated with enrichment of opportunistic pathogens were seen in IBSN.The symptoms of IBSP patients were relieved in different degrees after therapy,but the symptoms of IBSN rarely changed.We also found that the presence of IBSN-enriched genera(Enterobacter and Enterococcus)are unaffected by rifaximin therapy.Conclusions:IBS-D patients overlapping with SIBO showed noticeably different fecal microbial composition and function compared with IBS-D only.The better response to rifaximin in those comorbid patients might associate with their different gut microbiota,which suggests that BT is necessary before IBS-D diagnosis and use of rifaximin.Registration:Chinese Clinical Trial Registry,ChiCTR1800017911.展开更多
To the Editor:Increasing attention is being paid to preventing ulcerative colitis(UC)-associated carcinogenesis.The intestinal microbiota plays an important role in maintaining the intestinal barrier and immune functi...To the Editor:Increasing attention is being paid to preventing ulcerative colitis(UC)-associated carcinogenesis.The intestinal microbiota plays an important role in maintaining the intestinal barrier and immune function.Probiotic mixture VSL#3,that was bought from Sigma-Tau pharmaceuticals(De Simone Formulation)in May 2015,is a mixture of Lactobacillus casei,L.plantarum,L.acidophilus,L.delbrueckii subsp.bulgaricus,Bifidobacterium longum,B.breve,B.infantis and Streptococcus salivarius andcontains 4.5 billion live bacterialcolonies.i Previous studies have shown that VSL#3 can help induce and maintain UC remission.The effects of probiotics on UC-associated carcinogenesis are difficult to observe clinically;therefore,mouse models are often used to study this disease.Previous studies have shown that azoxymethane(AOM)combined with dextran sulfate sodium(DSS)can quickly induce a UC-associated carcinogenesis model.展开更多
基金supported by the National Natural Science Foundation of China(No.81670491)the Michigan Medicine-PKUHSC Joint Institute for Translational and Clinical Research(No.BMU20140478).
文摘Background:As a non-invasive and effective diagnostic method for small intestinal bacterial overgrowth(SIBO),wild-use of breath test(BT)has demonstrated a high comorbidity rate in patients with diarrhea-predominant irritable bowel syndrome(IBS-D)and SIBO.Patients overlapping with SIBO respond better to rifaximin therapy than those with IBS-D only.Gut microbiota plays a critical role in both of these two diseases.We aimed to determine the microbial difference between IBS-D overlapping with/without SIBO,and to study the underlying mechanism of its sensitivity to rifaximin.Methods:Patients with IBS-D were categorized as BT-negative(IBSN)and BT-positive(IBSP).Healthy volunteers(BT-negative)were enrolled as healthy control.The patients were clinically evaluated before and after rifaximin treatment(0.4 g bid,4 weeks).Blood,intestine,and stool samples were collected for cytokine assessment and gut microbial analyses.Results:Clinical complaints and microbial abundance were significantly higher in IBSP than in IBSN.In contrast,severe systemic inflammation and more active bacterial invasion function that were associated with enrichment of opportunistic pathogens were seen in IBSN.The symptoms of IBSP patients were relieved in different degrees after therapy,but the symptoms of IBSN rarely changed.We also found that the presence of IBSN-enriched genera(Enterobacter and Enterococcus)are unaffected by rifaximin therapy.Conclusions:IBS-D patients overlapping with SIBO showed noticeably different fecal microbial composition and function compared with IBS-D only.The better response to rifaximin in those comorbid patients might associate with their different gut microbiota,which suggests that BT is necessary before IBS-D diagnosis and use of rifaximin.Registration:Chinese Clinical Trial Registry,ChiCTR1800017911.
基金The study was funded by grants from National Natural Science Foundation of China(Nos.81370500 and 81770559)。
文摘To the Editor:Increasing attention is being paid to preventing ulcerative colitis(UC)-associated carcinogenesis.The intestinal microbiota plays an important role in maintaining the intestinal barrier and immune function.Probiotic mixture VSL#3,that was bought from Sigma-Tau pharmaceuticals(De Simone Formulation)in May 2015,is a mixture of Lactobacillus casei,L.plantarum,L.acidophilus,L.delbrueckii subsp.bulgaricus,Bifidobacterium longum,B.breve,B.infantis and Streptococcus salivarius andcontains 4.5 billion live bacterialcolonies.i Previous studies have shown that VSL#3 can help induce and maintain UC remission.The effects of probiotics on UC-associated carcinogenesis are difficult to observe clinically;therefore,mouse models are often used to study this disease.Previous studies have shown that azoxymethane(AOM)combined with dextran sulfate sodium(DSS)can quickly induce a UC-associated carcinogenesis model.
