Abstract: The purpose of this study was to investigate the influence of an antibiotic policy programme based on restriction of the empirical use of fluoroquinolones and ceftazidime on the susceptibilities of Gram-negative microorganisms in a general Intensive Care Unit (ICU). The epidemiology of infections caused by the predominant ICU pathogens, i.e. Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae, and their resistance patterns as well as antibiotic consumption were recorded for a 6-month period. An antibiotic restriction policy including ceftazidime and quinolones was applied. After an 18-month period of protocol application, the same parameters were recorded for another 6-month period. Consumption of restricted and overall antibiotics was reduced by 92.5% and 55.4%, respectively. Susceptibilities to ciprofloxacin of the three predominant infection-causing Gram-negative bacilli were significantly increased. Ceftazidime showed an increase in susceptibility only for P. aeruginosa. Similar rates of infectious episodes were recorded in the two periods and no differences were observed either in overall mortality or in ICU ecology as expressed by the type of microorganisms implicated in colonisation and/or infection. The reported data suggest that an antibiotic restriction policy can significantly reduce antimicrobial consumption and antimicrobial resistance rates, although the latter effect can be also influenced by the prevalent resistance mechanisms and the prevalence of imported resistance.
Abstract: Post-surgical meningitis and/or ventriculitis caused by Gram-negative bacteria may be difficult to treat due to the emergence of multiresistant strains. Two patients with multiresistant Acinetobacter baumannii central nervous system infection, successfully treated with either intravenous and/or intraventricular colistin are presented. Unresolved issues such as dose and duration of intraventricular colistin are discussed.
Abstract: Klebsiella pneumoniae that was resistant to all available antibiotics (minimum inhibitory concentration of imipenem, 32 microg/mL), including carbapenems, was isolated from blood samples obtained from a 48-year-old patient in the intensive care unit. The patient developed septic shock, which was successfully treated with colistin, the only antibiotic with activity against this multidrug-resistant strain.
Abstract: A matched case-control study was performed to identify risk factors for acquiring multidrug-resistant Pseudomonas aeruginosa (MDRPA) in intensive care unit (ICU) patients during a 2-year period. MDRPA was defined as P. aeruginosa with combined decreased susceptibility to piperacillin, ceftazidime, imipenem, and ciprofloxacin. Thirty-seven patients who were colonized or infected with MDRPA were identified, 34 of whom were matched with 34 control patients who had cultures that showed no growth of P. aeruginosa. Matching criteria were severity of illness and length of ICU stay, with each control patient staying in the ICU for at least as long as the time period between the corresponding case patient's admission to the ICU and the acquisition of MDRPA. Baseline demographic and clinical characteristics and the use of invasive procedures were similar for case patients and control patients. Multivariate analysis identified duration of ciprofloxacin treatment as an independent risk factor for MDRPA acquisition, whereas the duration of treatment with imipenem was of borderline significance. These data support a major role for the use of antibiotics with high antipseudomonal activity, particularly ciprofloxacin, in the emergence of MDRPA.
