title: Antimicrobial use and resistance among Gram-negative bacilli in an Italian intensive care unit (ICU).
abstract: Gram-negative bacilli antimicrobial resistance remains a significant problem for patients in the intensive care unit (ICU). We performed a retrospective analysis of microbiological data and antibiotic consumption over a 4-year period (2000-2003) in an Italian ICU. Pseudomonas aeruginosa and Klebsiella pneumoniae represented approximately 40% of all isolates. The most significant trend in antimicrobial use was an increase in use of 3(rd )generation cephalosporins, imipenem, and ciprofloxacin. A significant trend toward an increase in resistance rates to piperacillin, 3( rd )generation cephalosporins and ciprofloxacin was observed for K. pneumoniae and a positive correlation between resistance and drug-usage was evident for K. pneumoniae and piperacillin, cefotaxime, ceftazidime, cefepime, and ciprofloxacin, but not for piperacillin/tazobactam. No statistically significant correlations were evidenced for P. aeruginosa. Trends in resistances were studied also for Serratia spp and Proteus spp. Isolation rates of extended-spectrum beta-lactamase (ESBL)-producing strains in pathogens studied were high, especially for K. pneumoniae (72%, 160/222) and Proteus spp (41%, 18/43). In conclusion, the study showed high resistance among Gram-negative organisms isolated in the ICU and significant ESBL production. A significant correlation between antibiotic consumption and increasing resistance was evident for K. pneumoniae.
authors.affiliation: Department of Infectious Diseases, University of Genoa School of Medicine, San Martino Hospital, Genoa, Italy. matteo.bassetti@hsanmartino.it
authors.forename: M
authors.initials: M
authors.lastname: Bassetti
authors.forename: M
authors.initials: M
authors.lastname: Cruciani
authors.forename: E
authors.initials: E
authors.lastname: Righi
authors.forename: B
authors.initials: B
authors.lastname: Rebesco
authors.forename: R
authors.initials: R
authors.lastname: Fasce
authors.forename: A
authors.initials: A
authors.lastname: Costa
authors.forename: M P
authors.initials: MP
authors.lastname: Molinari
authors.forename: C
authors.initials: C
authors.lastname: Mengoli
authors.forename: F
authors.initials: F
authors.lastname: Bobbio Pallavicini
authors.forename: C
authors.initials: C
authors.lastname: Viscoli
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D003428:Cross Infection / Q000188:drug therapy* / Q000382:microbiology; D003710:Demography; D024901:Drug Resistance, Multiple, Bacterial; D004363:Drug Utilization; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D007362:Intensive Care Units; D007558:Italy / Q000453:epidemiology; D007902:Length of Stay; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents