Failure of dietary oligofructose to prevent antibiotic-associated diarrhoea.
BACKGROUND
Oligofructose is metabolized by bifidobacteria, increasing their numbers in the colon. High bifidobacteria concentrations are important in providing 'colonization resistance' against pathogenic bacteria.


OBJECTIVE
To reduce the incidence of antibiotic-associated diarrhoea in elderly patients.


METHODS
Patients over the age of 65 taking broad-spectrum antibiotics received either oligofructose or placebo. A baseline stool sample was cultured for Clostridium difficile and tested for C. difficile toxin. A further stool sample was analysed for C. difficile if diarrhoea developed.


RESULTS
No difference was seen in the baseline characteristics, incidence of diarrhoea, C. difficile infection or hospital stay between the two groups (n = 435). Oligofructose increased bifidobacterial concentrations (P < 0.001, 95% CI: 0.69-1.72). A total of 116 (27%) patients developed diarrhoea of which 49 (11%) were C. difficile-positive and were more likely to be taking a cephalosporin (P = 0.006), be female (P < 0.001), to have lost more weight (P < 0.001, 95% CI: 0.99-2.00) and stayed longer in hospital (P < 0.001, 95% CI: 0.10-1.40). Amoxicillin (amoxycillin) and clavulanic acid increased diarrhoea not caused by C. difficile (P = 0.006).


CONCLUSIONS
Oligofructose does not protect elderly patients receiving broad-spectrum antibiotics from antibiotic-associated diarrhoea whether caused by C. difficile or not. Oligofructose was well-tolerated and increased faecal bifidobacterial concentrations.
Lewis
S
S
Department of Medicine, Addenbrooke's Hospital, Cambridge, UK. sjl@dircon.co.uk
Burmeister
S
S
Cohen
S
S
Brazier
J
J
Awasthi
A
A
D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D016360:Clostridioides difficile / Q000302:isolation & purification; D003015:Clostridium Infections / Q000139:chemically induced / Q000150:complications / Q000517:prevention & control; D003967:Diarrhea / Q000139:chemically induced / Q000382:microbiology / Q000517:prevention & control*; D004311:Double-Blind Method; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D009844:Oligosaccharides / Q000627:therapeutic use*
D000900:Anti-Bacterial Agents; D009844:Oligosaccharides; C120489:oligofructose