Diagnostic microbiology and infectious disease
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Diagn. Microbiol. Infect. Dis. · Sep 2006
Multicenter StudyAntimicrobial susceptibility pattern comparisons among intensive care unit and general ward Gram-negative isolates from the Meropenem Yearly Susceptibility Test Information Collection Program (USA).
The Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program is a global, longitudinal antimicrobial resistance surveillance network of greater than 100 medical centers worldwide monitoring the susceptibility of bacterial pathogens to carbapenems and other broad-spectrum agents. Between 1999 and 2002, 15 US medical centers referred up to 200 nonduplicate isolates from clinical infections to a central processing laboratory. During this 4-year period, the antimicrobial activity of 11 broad-spectrum agents was assessed against 5389 bacterial isolates using Clinical and Laboratory Standards Institute (formerly National Committee for Clinical Laboratory Standards)-recommended methods with interpretive criteria. ⋯ For the nonfermentative Gram-negative bacilli, the rank order of the most active agents having lowest percentage resistance rates were tobramycin (15.5%) < cefepime < imipenem < piperacillin/tazobactam < ceftazidime < meropenem (21.9%) for ICU isolates, and meropenem (7.8%) < cefepime < imipenem < piperacillin/tazobactam < ceftazidime < tobramycin (12.9%) among non-ICU strains. All tested agents showed lower susceptibility rates (range, 1.0-15.3%) and higher resistance rates (range, 0.1-15.1%) for both Enterobacteriaceae and nonfermentative Gram-negative bacilli among the ICU isolates compared to the non-ICU isolates (except for ciprofloxacin against Enterobacteriaceae). Continued surveillance of these broad-spectrum antimicrobial agents in both ICU and general hospital wards appears warranted to monitor the occurrence and spread of antimicrobial resistance in pathogens causing serious infections in these care areas and the possible emergence of resistance mechanisms that could compromise empiric carbapenem therapy.
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Diagn. Microbiol. Infect. Dis. · Sep 2006
Enteric pathogens associated with diarrhea in children in Fayoum, Egypt.
In a cross-sectional study of children <60 months old from Fayoum, Egypt, presenting with diarrhea, 46% (162/356) had detectable enteric pathogens. Bacterial pathogens were identified in 25% (89/356), whereas rotavirus and Cryptosporidium were detected in 21% (54/253) and 15% (39/253), respectively. Cryptosporidium is an important pathogen in this region.
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Diagn. Microbiol. Infect. Dis. · Aug 2006
Comparative StudyThe association between anatomic site of Candida colonization, invasive candidiasis, and mortality in critically ill surgical patients.
We evaluated whether the likelihood of developing invasive candidiasis (IC) differed depending upon the anatomic site of Candida colonization in 182 surgical intensive care unit (SICU) patients who participated in a randomized trial of fluconazole to prevent candidiasis. We also determined the impact of Candida colonization of different anatomic sites on all-cause SICU and hospital mortality. A total of 2851 surveillance fungal cultures collected from 5 anatomic sites were analyzed. ⋯ Patients with negative rectum/ostomy cultures and patients with both negative urine and respiratory tract cultures did not develop IC. Candiduria detected at any time in the SICU was independently associated with SICU mortality (odds ratio, 2.86; 95% confidence interval, 1.05-7.74). Surveillance fungal cultures of particular anatomic sites may help differentiate patients at higher risk of developing IC from those at low risk.
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Diagn. Microbiol. Infect. Dis. · Jul 2006
Increasing trend in the prevalence of plasmid-mediated AmpC beta-lactamases in Enterobacteriaceae lacking chromosomal ampC gene at a Korean university hospital from 2002 to 2004.
The aim of the study is to investigate the prevalence of plasmid-mediated AmpC beta-lactamases in Enterobacteriaceae naturally lacking chromosomal AmpC beta-lactamases. A total of 1860 clinical isolates of Klebsiella spp., Salmonella spp., and Proteus mirabilis were collected from a Korean hospital between January 2002 and December 2004. For the isolates that are nonsusceptible to cefoxitin, polymerase chain reaction amplification of the bla(SHV), bla(TEM), and bla(AmpC) genes and sequencing were performed. ⋯ The DHA-1-producing K. pneumoniae was only 2 isolates (0.6%) in 2002, but the rate and the number significantly increased to 2.4% (13 of 538 isolates) in 2003 and to 4.3% (22 of 512) in 2004. In conclusion, DHA-1 is the most prevalent plasmid-mediated AmpC beta-lactamase in Enterobacteriaceae lacking chromosomal ampC gene, and the DHA-1-producing K. pneumoniae isolates have rapidly increased since 2003 in a Korean hospital. In addition, this is the first report of the appearance of a K. pneumoniae isolate producing ACT-1 beta-lactamase in Korea.
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Diagn. Microbiol. Infect. Dis. · Jun 2006
Community-onset Escherichia coli and Klebsiella pneumoniae bacteremia: influence of health care exposure on antimicrobial susceptibility.
Three hundred forty-one case patients with Escherichia coli bacteremia and 173 case patients with Klebsiella pneumoniae bacteremia were enrolled in this prospective observational study to compare the clinical manifestations of infections in the 2 organisms and to delineate the change in resistance of isolates after health care exposure. Liver abscess, primary bacteremia, and respiratory tract infection were more commonly seen in patients with K. pneumoniae bacteremia, whereas urinary tract infection was more common in those with E. coli bacteremia. ⋯ Patients undergoing procedures in the outpatient setting and nursing home residents also had infections with more resistant E. coli strains than those without hospital exposure within the previous year. However, no difference in resistance was observed in K. pneumoniae isolates from patients in different clinical settings.