THE ROLE OF GUT MICROBIOME IN POST-INFECTIOUS DIARRHEA RECOVERY

Abstract

Post-infectious diarrhea (PID) persists in some individuals following the resolution of acute enteric infections and is often associated with gut microbiota disturbances. This study aimed to investigate the microbial, metabolic, immunological, and clinical characteristics associated with delayed recovery in PID patients, compared to healthy controls.
A total of 100 people took part, including 60 with post-infectious diarrhoea and 40 healthy people who matched them by age and sex.  Microbiota assessment was done by analyzing the 16S rRNA sequence of stool samples.  The measurement of acetate and butyrate, as SCFAs, was possible using a gas chromatography–mass spectrometry technique.  Studies of the blood samples showed levels of IL-6, TNF-α and zonulin.  Weekly diarrhoea severity scores given by patients were self-reported. T-tests, Spearman correlation and multivariate regression methods assessed the relationships and factors.  Considering both Shannon (2.51 vs. 3.39) and Simpson indices (0.78 vs. 0.89), the microbial variety was lower for PID patients.  The SCFA levels in the PID group were much lower than those in the control group: butyrate was 18.2 µmol/g and acetate was 34.6 µmol/g, whereas in the SCFA group, butyrate was 25.9 µmol/g and acetate was 42.2 µmol/g.  Measuring zonulin in the intestines, we found its levels were high (62.4 ng/mL versus 38.3 ng/mL in the control group).  Standard values for IL-6 and TNF-α are 5.6 pg/mL and 9.2 pg/mL, respectively and are both seen to rise to 12.3 pg/mL and 17.9 pg/mL.  Diarrhoea severity was very high in PID patients, with a mean score of 6.8 and only 1.2 for control patients.  All the differences were statistically important—p < 0.01.  A decrease in SCFA, important changes in gut bacteria, raised gut permeability and ongoing inflammation together explain why it takes longer to recover from post-infectious diarrhoea.  Altering the bacteria in the gut could help people with these illnesses recover.