Extended-spectrum beta-lactamase-producing Enterobacteriaceae in an Italian intensive care unit: clinical and therapeutical remarks.
In this study we evaluated the prevalence of Enterobacteriaceae and the epidemiology of ESBL+ microorganisms in an ICU of our Institution over a 5-year period and analyzed the clinical features and outcomes of the infections caused by these microorganisms. The most frequent ESBL+ isolate was Proteus mirabilis (69 isolates, 58%); a high rate of positive results in the double-disk synergy test (DDS) was also recognized for Klebsiella pneumoniae (52 isolates, 51%), whereas this phenomenon was observed less frequently in other species. In 312 cases the isolated microorganism was considered to be the cause of infection; we documented 103 wound infections, 89 UTIs, 62 LRTIs, 30 primary bacteremias, 27 infections of indwelling catheters and 1 CNS infection. The overall mortality rate due to ESBL+ strains was 1%, compared with 10.6% rate caused by ESBL-negative Enterobacteriaceae. This could be explained because ESBL+ strains caused mostly localized infections (wound infections and UTIs), whereas systemic or severe infections were sustained by ESBL-negative strains, and therapy with carbapenems was started promptly after ESBL+ isolation (always within 24h after strain isolation).
Carretto
E
E
Laboratori Sperimentali di Ricerca, Area Infettivologica, IRCCS Policlinico San Matteo, Pavia, Italy. e.carretto@smatteo.pv.it
Emmi
V
V
Barbarini
D
D
Capra Marzani
F
F
Bolongaro
A
A
Braschi
A
A
Marone
P
P
D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D003428:Cross Infection / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control; D004755:Enterobacteriaceae / Q000187:drug effects / Q000302:isolation & purification* / Q000378:metabolism; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control; D006801:Humans; D017053:Infection Control; D007362:Intensive Care Units; D007558:Italy / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D001618:beta-Lactamases / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases