In vitro activity of daptomycin versus linezolid and vancomycin against gram-positive uropathogens and ampicillin against enterococci, causing complicated urinary tract infections.
OBJECTIVE
The existing therapeutic options for complicated urinary tract infections (UTI) caused by gram-positive uropathogens are not always optimal. Therefore, newer antimicrobials have to be assessed.


METHODS
The antimicrobial activity of daptomycin was tested versus linezolid, vancomycin, and ampicillin (enterococci on ly), against pathogens from three different collections: (1) Uropathogens from hospitalized urological patients with complicated and/or hospital-acquired UTIs of the Urologic Clinic, Hospital St. Elisabeth, Straubing. (2) Uropathogens from a multicenter study comprising 37 urological centers throughout Germany. (3) Methicillin-resistant Staphylococcus aureus (MRSA) isolates of patients and staff within the Hospital St. Elisabeth, Straubing. Genotyping of the latter isolates was performed by pulsed-field gel electrophoresis. The minimal inhibitory concentrations (MIC) of daptomycin, linezolid, vancomycin, and ampicillin (only tested against enterococci) were determined by an agar dilution method using a multipointer with an inoculum of 10(4) CFU per point.


RESULTS
For all methicillin-susceptible Staphylococcus aureus (n = 25), MRSA (n = 49), methicillin-susceptible coagulase-negative staphylococci (n = 129), methicillin-resistant coagulase-negative staphylococci (n = 33), for Enterococcus faecalis (n = 289), and for Enterococcus faecium (n = 4) the MICs ranged up to 2 mg/l (daptomycin, linezolid), up to 4 mg/l (vancomycin), and up to 8 mg/l (ampicillin, enterococci only) indicating that all strains were susceptible to the antibiotics tested.


CONCLUSIONS
According to the in vitro activity daptomycin may be considered a promising antibacterial agent for the treatment of complicated UTI caused by gram-positive uropathogens. Thus, daptomycin should be evaluated in a clinical study.
Wagenlehner
Florian M E
FM
Department of Urology, St. Elisabeth Hospital, Straubing, Germany.
Lehn
Norbert
N
Witte
Wolfgang
W
Naber
Kurt G
KG
D000081:Acetamides / Q000494:pharmacology; D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003428:Cross Infection / Q000382:microbiology / Q000652:urine; D017576:Daptomycin / Q000494:pharmacology; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D005838:Genotype; D006801:Humans; D000069349:Linezolid; D008826:Microbial Sensitivity Tests; D023303:Oxazolidinones / Q000494:pharmacology; D013210:Staphylococcus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D014552:Urinary Tract Infections / Q000382:microbiology* / Q000652:urine; D014640:Vancomycin / Q000494:pharmacology
D000081:Acetamides; D000900:Anti-Bacterial Agents; D023303:Oxazolidinones; D014640:Vancomycin; D000667:Ampicillin; D000069349:Linezolid; D017576:Daptomycin