Emergence of Klebsiella pneumoniae carrying the novel extended-spectrum beta-lactamase gene variants bla(SHV-40), bla(TEM-116) and the class 1 integron-associated bla(GES-7) in Brazil.

A clinical Klebsiella pneumoniae isolate carrying the extended-spectrum beta-lactamase gene variants bla(SHV-40), bla(TEM-116) and bla(GES-7) was recovered. Cefoxitin and ceftazidime activity was most affected by the presence of these genes and an additional resistance to trimethoprim-sulphamethoxazole was observed. The bla(GES-7) gene was found to be inserted into a class 1 integron. These results show the emergence of novel bla(TEM) and bla(SHV) genes in Brazil. Moreover, the presence of class 1 integrons suggests a great potential for dissemination of bla(GES) genes into diverse nosocomial pathogens. Indeed, the bla(GES-7) gene was originally discovered in Enterobacter cloacae in Greece and, to our knowledge, has not been reported elsewhere.

Carbapenem-resistant Acinetobacter baumannii outbreak at university hospital / Caracterização de cepas de Acinetobacter baumannii durante um surto de infecção hospitalar

Nineteen clonally related imipenem-resistant Acinetobacter baumannii isolates were recovered from eight intensive care unit patients. All isolates harboured blaOXA-51-like â-lactamase genes and showed the absence of 22 kDa fraction in outer membrane porin profile analysis. It suggests a combination of two mechanisms as responsible for carbapenemresistant phenotypes.

Foram isoladas 19 cepas monoclonais de 8 pacientes da unidade de terapia intensiva, resistentes aos carbapenêmicos. Todas as cepas apresentaram o gene blaOXA-51-like e por análise do perfil de proteínas de membrana notou-se ausência da fração de 22 kDa, sugerindo a combinação de dois mecanismos de resistência aos carbapenêmicos.

Risk factors for colonisation of newborn infants during an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in an intermediate-risk neonatal unit.

We describe a cross-sectional survey to identify risk factors for colonisation of neonates by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae. This occurred following exposure to a colonised healthcare worker during an outbreak in an intermediate-risk neonatal unit. In total, 120 neonates admitted consecutively during a three-month period were screened for ESBL-producing K. pneumoniae by rectal swabbing and 27 were identified as colonised. Multivariate analysis showed colonisation to be independently associated with use of antibiotics and absence of breastfeeding. Previous use of antibiotics presented an odds ratio (OR) of 12.3 [95% confidence interval (CI): 3.66-41.2, P<0.001]. The most commonly used antibiotics were penicillin and amikacin. Breastfeeding was associated with reduced risk for colonisation (OR: 0.22; 95% CI: 0.05-0.99; P=0.049). Nine isolates recovered during the first stage of the outbreak and 27 isolates from surveillance cultures were typed thereafter by pulsed-field gel electrophoresis, revealing six different profiles (A-F). Clones A, C, and E were implicated in the first stage of the outbreak, whereas among the 27 strains recovered from surveillance cultures, all six clones were identified. Clone A was also found on the hand of a nursing auxiliary with onychomycosis. We concluded that prior antimicrobial use predisposed to colonisation. The possible role of breastfeeding as a protective factor needs to be further elucidated. Detection of different genotypes of ESBL-producing K. pneumoniae suggests that dissemination of mobile genetic elements bearing the ESBL gene may have been superimposed on the simple dissemination of a clone during the outbreak.

Carbapenem-resistant Acinetobacter baumannii outbreak at university hospital.

Nineteen clonally related imipenem-resistant Acinetobacter baumannii isolates were recovered from eight intensive care unit patients. All isolates harboured bla OXA-51-like ß-lactamase genes and showed the absence of 22 kDa fraction in outer membrane porin profile analysis. It suggests a combination of two mechanisms as responsible for carbapenem-resistant phenotypes.

Educational intervention program to optimize the use of antibiotics: impact on prescribing habits, consumption of antimicrobial agents and cost savings

Antimicrobials are among the most frequently used drugs worldwide, especially in developing countries, where there are limited data on the use of these therapeutic agents. The Pharmacy Service and the Hospital Infection Control Commission (HICC) of a medium complexity university hospital, concerned about the rational use of broad-spectrum antimicrobials, have devised a sequential intervention program to improve the use of the antibiotics ceftazidime, ciprofloxacin, imipenem and vancomycin in Intensive Care Units (ICUs). The program was developed in three successive steps lasting six months each: baseline data collection (November 2001 to April 2002), initial intervention period (May 2002 to October 2002), educational intervention program (November 2002 to April 2003). All the ICU antimicrobial prescriptions were reviewed and consumption was converted into Defi ned Daily Doses per 100 patient-days and tabulated to compare different periods and the respective costs. A total of 459 ICU patients were followed through. A change in the profile of antimicrobial prescriptions was observed: a reduction in the use of broad spectrum antimicrobials, reduced number of antimicrobials per patient and improvement in etiological investigation of infection. Significant reductions of ciprofl oxacin (69.2%), imipenem (56.3%) and vancomycin (39.0%) consumption were observed. Total cost savings, based on the data for the four drugs, was US$31,523.58 (58.6%). The multidisciplinary educational intervention program was thus responsible for both an improvement in the use of broad-spectrum antimicrobials in the ICU and cost savings.

Staphylococcus aureus bacteremia: what is the impact of oxacillin resistance on mortality?

In order to analyse the impact of oxacillin resistance on the mortality of Staphylococcus aureus bacteremia, and to assess the antimicrobial susceptibility of community-acquired strains in two large university hospitals (the Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo and the Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo), we carried out a four-month-long prospective cohort study, which included 163 consecutive cases of S. aureus bacteremia. Of these, 140 (85.9%) were hospital-acquired, 9 (5.5%) were community-acquired and 14 (8.6%) were of indeterminate origin. No cases of community-acquired infection by oxacillin-resistant S. aureus was identified. Among hospital-acquired infections, oxacillin-resistant S. aureus was responsible for 64.3% of cases. Mortality up to 15 days after diagnosis of bacteremia was 27% (18/67) for infections caused by susceptible strains and 33% (32/96) for infections caused by oxacillin-resistant strains (p=0.10). The following independent risk factors for the acquisition of oxacillin-resistant S. aureus were identified in multiple logistical regression analysis: age over 60 years, use of corticoids; presence of a central vascular catheter, and previous use of antibiotics.

Staphylococcus aureus bacteremia: what is the impact of oxacillin resistance on mortality?

In order to analyse the impact of oxacillin resistance on the mortality of Staphylococcus aureus bacteremia, and to assess the antimicrobial susceptibility of community-acquired strains in two large university hospitals (the Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo and the Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo), we carried out a four-month-long prospective cohort study, which included 163 consecutive cases of S. aureus bacteremia. Of these, 140 (85.9 percent) were hospital-acquired, 9 (5.5 percent) were community-acquired and 14 (8.6 percent) were of indeterminate origin. No cases of community-acquired infection by oxacillin-resistant S. aureus was identified. Among hospital-acquired infections, oxacillin-resistant S. aureus was responsible for 64.3 percent of cases. Mortality up to 15 days after diagnosis of bacteremia was 27 percent (18/67) for infections caused by susceptible strains and 33 percent (32/96) for infections caused by oxacillin-resistant strains (p=0.10). The following independent risk factors for the acquisition of oxacillin-resistant S. aureus were identified in multiple logistical regression analysis: age over 60 years, use of corticoids; presence of a central vascular catheter, and previous use of antibiotics.