Comparison of hospital-wide and unit-specific cumulative antibiograms in hospital- and community-acquired infection.
BACKGROUND
Empirical antibacterial therapy in hospitals is usually guided by local epidemiologic features reflected by institutional cumulative antibiograms. We investigated additional information inferred by aggregating cumulative antibiograms by type of unit or according to the place of acquisition (i.e. community vs. hospital) of the bacteria.


METHODS
Antimicrobial susceptibility rates of selected pathogens were collected over a 4-year period in an university-affiliated hospital. Hospital-wide antibiograms were compared with those selected by type of unit and sampling time (<48 or >48 h after hospital admission).


RESULTS
Strains isolated >48 h after admission were less susceptible than those presumably arising from the community (<48 h). The comparison of units revealed significant differences among strains isolated >48 h after admission. When compared to hospital-wide antibiograms, susceptibility rates were lower in the ICU and surgical units for Escherichia coli to amoxicillin-clavulanate, enterococci to penicillin, and Pseudomonas aeruginosa to anti-pseudomonal beta-lactams, and in medical units for Staphylococcus aureus to oxacillin. In contrast, few differences were observed among strains isolated within 48 h of admission.


CONCLUSIONS
Hospital-wide antibiograms reflect the susceptibility pattern for a specific unit with respect to community-acquired, but not to hospital-acquired strains. Antibiograms adjusted to these parameters may be useful in guiding the choice of empirical antibacterial therapy.
Lamoth
F
F
Infectious Diseases Service, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Rue du Bugnon 46, 1011 Lausanne, Switzerland. Frederic.Lamoth@chuv.ch
Wenger
A
A
Prod'hom
G
G
Vallet
Y
Y
Plüss-Suard
C
C
Bille
J
J
Zanetti
G
G
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D001424:Bacterial Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D016021:Epidemiologic Studies; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects; D013557:Switzerland / Q000453:epidemiology
D000900:Anti-Bacterial Agents