Effects ofSaccharomyces boulardiion fecal short-chain fatty acids and microflora in patients on long-term total enteral nutrition

Diarrhea is a significant problem in patients on total enteral nutrition (TEN) and may involve changes in intestinal short chain fatty acids or microflora. Recent studies suggest that the probiotic yeast Saccharomyces boulardii (Sb) may decrease its incidence. The aim of this study was to assess the effects of Sb on fecal flora and short-chain fatty acids (SCFA) in patients on long-term TEN.Ten patients (3 females, 7 males, 59+/-5.5 years), on TEN for a median of 13 mo (1-125), and 15 healthy volunteers (4 females, 11 males, 32+/-2.0 years) received Sb (0.5 g bid PO) for 6 d. Two stool samples were taken before, on the last 2 d and 9-10 d after treatment, for SCFA measurement and for culture and bacterial identification. Values (mean+/-SE) were compared using sign tests and ANOVA.Fecal butyrate levels were lower in patients (10.1+/-2.9 mmol/kg) than in controls (19.2+/-3.9, P = 0.02). Treatment with Sb increased total fecal SCFA levels in patients (150.2+/-27.2 vs 107.5+/-18.2 mmol/kg, P = 0.02) but not in controls (129.0+/-28.6 vs 113.0+/-15.2 mmol/kg, NS). At the end of treatment with Sb, patients had higher fecal butyrate (16.0+/-4.4 vs 10.1 [2.9] mmol/kg, P = 0.004). Total SCFAs remained high 9 d after treatment was discontinued. Before the treatment, the anaerobe to aerobe ratio was lower in patients compared to controls (2.4+/-2.3 vs 69.8+/-1.8, P = 0.003). There were no significant changes in the fecal flora of TEN patients.Sb-induced increase of fecal SCFA concentrations (especially butyrate) may explain the preventive effects of this yeast on TEN-induced diarrhea.