Effect of Lactobacillus F19 on the emergence of antibiotic-resistant microorganisms in the intestinal microflora.
OBJECTIVE
Probiotic lactic-acid-producing bacteria have been used for prevention of gastrointestinal diseases. The aim of the present study was to examine whether Lactobacillus F19 in conjunction with treatment with penicillin, ciprofloxacin or norfloxacin prevents establishment of resistant bacteria in the gastrointestinal tract.


METHODS
Twenty patients admitted to hospital due for treatment with penicillin and 16 patients due for treatment with ciprofloxacin or norfloxacin were included in the study. In either group, the patients were randomized into two groups, receiving placebo or an active probiotic product. Faecal samples were collected before treatment, on day 10 and 1 month after the start of the treatment. Isolates of enterococci, enterobacteria and Bacteroides fragilis species were screened for resistance to penicillin and ciprofloxacin, respectively.


RESULTS
Administration of penicillin did not influence resistance in enterococci while quinolone resistance increased during quinolone treatment. Susceptibility to ampicillin and piperacillin/tazobactam decreased in enterobacteria during penicillin treatment and ciprofloxacin resistance increased in the quinolone group. Penicillin and quinolones did not influence the resistance rates of Bacteroides isolates. No major differences were observed between the probiotic- and placebo-supplemented groups.


CONCLUSIONS
There was a limited effect of Lactobacillus F19 on the emergence of resistant isolates during treatment with penicillin and quinolones.
Divisions of Clinical Bacteriology, F82, Karolinska University Hospital Huddinge, SE-141 86 Stockholm, Sweden.
Asa
A
Sullivan
Anita
A
Johansson
Bo
B
Svenungsson
Carl Erik
CE
Nord
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D001441:Bacteroides fragilis / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D004311:Double-Blind Method; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D004755:Enterobacteriaceae / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D016983:Enterococcus / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D024841:Fluoroquinolones / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007778:Lactobacillus / Q000502:physiology*; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010406:Penicillins / Q000008:administration & dosage / Q000627:therapeutic use; D019936:Probiotics / Q000008:administration & dosage*; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D010406:Penicillins