Format

Send to

Choose Destination
Clin Infect Dis. 2006 Mar 1;42(5):e35-44. Epub 2006 Jan 25.

Lactobacillus bacteremia, species identification, and antimicrobial susceptibility of 85 blood isolates.

Author information

1
Division of Infectious Diseases, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland. minna.salminen@hus.fi

Abstract

BACKGROUND:

Data regarding antimicrobial susceptibility of clinical Lactobacillus isolates are scarce, and appropriate interpretation criteria for susceptibility tests are not available.

METHODS:

We examined 85 cases of Lactobacillus bacteremia, of which 47 cases have been included in our previous studies. Overall, 14 antimicrobial agents were evaluated by the E-test method, and these results were compared with disk diffusion test findings. The clinical outcomes of the patients and their antimicrobial treatments were registered.

RESULTS:

The antimicrobial susceptibility of Lactobacillus strains was species dependent. The considerable number of Lactobacillus rhamnosus (n=46), Lactobacillus fermentum (n=12), and Lactobacillus casei (n=12) strains available for testing made it possible to compare the susceptibilities within 1 species, as well. Of the 46 L. rhamnosus isolates, 22 were identified as L. rhamnosus GG type by pulsed-field gel electrophoresis. All Lactobacillus isolates demonstrated low minimum inhibitory concentrations (MICs) of imipenem, piperacillin-tazobactam, erythromycin, and clindamycin. MICs of vancomycin were high (>256 microg/mL) for all other species except Lactobacillus gasseri and Lactobacillus jensenii. Disk diffusion and E-test results were concordant. The MICs of cephalosporins varied; cefuroxime demonstrated a higher level of activity than did ceftriaxone. Benzylpenicillin and ampicillin MICs had variable ranges between different species. Combination therapy was given to 83% of the patients, but, in 54% of them, therapy included only 1 microbiologically active agent, according to results of the susceptibility tests. Mortality at 1 week was 12% among patients who presumably were receiving adequate treatment and 27% among patients who were receiving inadequate treatment (P=.131, by E-test).

CONCLUSION:

Most clinical Lactobacillus blood isolates demonstrated low MICs of imipenem, piperacillin-tazobactam, erythromycin, and clindamycin, but they had variable susceptibility to penicillin and cephalosporins.

PMID:
16447101
DOI:
10.1086/500214
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center