PT  - JOURNAL ARTICLE
AU  - Chaysavanh Manichanh
AU  - Anat Eck
AU  - Encarna Varela
AU  - Joaquim Roca
AU  - José C Clemente
AU  - Antonio González
AU  - Dan Knights
AU  - Rob Knight
AU  - Sandra Estrella
AU  - Carlos Hernandez
AU  - Denis Guyonnet
AU  - Anna Accarino
AU  - Javier Santos
AU  - Juan-R Malagelada
AU  - Francisco Guarner
AU  - Fernando Azpiroz
TI  - Anal gas evacuation and colonic microbiota in patients with flatulence: effect of diet
AID  - 10.1136/gutjnl-2012-303013
DP  - 2014 Mar 01
TA  - Gut
PG  - 401--408
VI  - 63
IP  - 3
4099  - http://gut.bmj.com/content/63/3/401.short
4100  - http://gut.bmj.com/content/63/3/401.full
SO  - Gut2014 Mar 01; 63
AB  - Objective To characterise the influence of diet on abdominal symptoms, anal gas evacuation, intestinal gas distribution and colonic microbiota in patients complaining of flatulence. Design Patients complaining of flatulence (n=30) and healthy subjects (n=20) were instructed to follow their usual diet for 3 days (basal phase) and to consume a high-flatulogenic diet for another 3 days (challenge phase). Results During basal phase, patients recorded more abdominal symptoms than healthy subjects in daily questionnaires (5.8±0.3 vs 0.4±0.2 mean discomfort/pain score, respectively; p=<0.0001) and more gas evacuations by an event marker (21.9±2.8 vs 7.4±1.0 daytime evacuations, respectively; p=0.0001), without differences in the volume of gas evacuated after a standard meal (262±22 and 265±25 mL, respectively). On flatulogenic diet, both groups recorded more abdominal symptoms (7.9±0.3 and 2.8±0.4 discomfort/pain, respectively), number of gas evacuations (44.4±5.3 and 21.7±2.9 daytime evacuations, respectively) and had more gas production (656±52 and 673±78 mL, respectively; p<0.05 vs basal diet for all). When challenged with flatulogenic diet, patients’ microbiota developed instability in composition, exhibiting variations in the main phyla and reduction of microbial diversity, whereas healthy subjects’ microbiota were stable. Taxa from Bacteroides fragilis or Bilophila wadsworthia correlated with number of gas evacuations or volume of gas evacuated, respectively. Conclusions Patients complaining of flatulence have a poor tolerance of intestinal gas, which is associated with instability of the microbial ecosystem.