Biological cost of fosfomycin resistance in Escherichia coli in a murine model of urinary tract infection.
Int J Med Microbiol
; 307(8): 452-459, 2017 Dec.
Article
in En
| MEDLINE
| ID: mdl-28986014
ABSTRACT
Prevalence of fosfomycin resistance in E. coli clinical isolates from UTIs remains very low. Our hypothesis was that fosfomycin resistance may be associated with a biological cost. Three groups of strains of E. coli belonging to the B2 phylogenetic group were used clinical wild-type (WT) isolates, clinical multidrug-resistant isolates and in vitro fosfomycin-resistant derivatives from the uropathogen clinical strain E. coli CFT073. In each group fosfomycin-susceptible and -resistant isolates were compared. In vitro, we found a significantly decreased growth rate for fosfomycin-resistant strains as compared with susceptible strains in the WT group. In a murine model of ascending UTI, there was a significant reduction in infection rates with fosfomycin-resistant isolates as compared with susceptible ones, in all 3 study groups, ranging from 28 to 39% (P<0.03). All fosfomycin-susceptible clinical strains were virulent in vivo (13/13), while fosfomycin-resistant clinical strains were either virulent (2/7) or non-virulent (5/7) (P<0.002). This difference was not explained by the number of virulence factors or pathogenicity-associated islands. In conclusion, fosfomycin resistance appears to carry some biological cost in E. coli, which may explain in part the apparent paradox of the low prevalence of fosfomycin resistance despite a high rate of spontaneous mutants.
Key words
Full text:
1
Collection:
01-internacional
Health context:
1_ASSA2030
/
2_ODS3
/
3_ND
Database:
MEDLINE
Main subject:
Urinary Tract Infections
/
Drug Resistance, Bacterial
/
Escherichia coli
/
Escherichia coli Infections
/
Genetic Fitness
/
Fosfomycin
/
Anti-Bacterial Agents
Type of study:
Health_economic_evaluation
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Animals
Language:
En
Journal:
Int J Med Microbiol
Year:
2017
Document type:
Article