Diagnostic microbiology and infectious disease
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Diagn. Microbiol. Infect. Dis. · Sep 2004
Multicenter Study Comparative StudyOccurrence and antimicrobial resistance pattern comparisons among bloodstream infection isolates from the SENTRY Antimicrobial Surveillance Program (1997-2002).
The empiric treatment of patients with bloodstream infections (BSI) has become more complicated in an era of increasing antimicrobial resistance. The SENTRY Antimicrobial Surveillance Program has monitored BSI from patients in medical centers worldwide since 1997. During 1997-2002, a total of 81,213 BSI pathogens from North America, Latin America, and Europe were tested for antimicrobial susceptibility. ⋯ Activity of commonly used antimicrobial agents remained relatively stable in North America, except in the case of vancomycin-resistant enterococci (20% decline between 1997 and 2002). An epidemiologic investigation of oxacillin-resistant S. aureus in North America identified 10 significant clones (ribotypes) and the common resistance patterns associated with them. Surveillance of BSI pathogens is needed to determine trends of resistance and provide useful information regarding patient risk factors and geographic differences.
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Diagn. Microbiol. Infect. Dis. · Sep 2004
Comparative StudyUnusual manifestations of histoplasmosis.
We present 6 cases of infection with Histoplasma capsulatum that have been uncommonly or not previously reported. Our case reports include unusual manifestations of H. capsulatum presenting as meningitis, the immune reconstitution syndrome, relapsing pericarditis, and scleroconjunctivitis.
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Diagn. Microbiol. Infect. Dis. · Aug 2004
Evaluation of procalcitonin as a marker of infection in a nonselected sample of febrile hospitalized patients.
The level of procalcitonin is undetectable in healthy individuals and slightly increased in viral infections and noninfectious inflammatory responses. It has been described to be notably increased in bacterial, parasitic, or fungal infections. Procalcitonin has been reported to be a reliable marker for severe bacterial infections, although it has mainly been studied in specific entities or in selected groups of patients. ⋯ Most of them had a proven (39) or probable bacterial infection (44). Procalcitonin was more frequently positive in bacteremic patients (p = 0.01), in patients with a proven bacterial infection (p < 0.01), and in those with a high sepsis score (p < 0.005), however; when cases with proven bacterial infection were considered as a reference, the sensitivity of the test was only 54% and the specificity 70%. Procalcitonin determination should not be included systematically in the screening of febrile hospitalized patients.
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Diagn. Microbiol. Infect. Dis. · Feb 2004
"Streptococcus milleri" endocarditis caused by Streptococcus anginosus.
Unlike other viridans streptococci, members of the "Streptococcus milleri group" are often associated with abscess formation, but are only rare causes of infective endocarditis. Although it has been shown that almost all S. intermedius isolates and most S. constellatus isolates, but only 19% of S. anginosus isolates, were associated with abscess formation, no report has addressed the relative importance of the 3 species of the "S. milleri group" in infective endocarditis. During a 5-year period (April 1997 through March 2002), 6 cases of "S. milleri" endocarditis (out of 377 cases of infective endocarditis), that fulfil the Duke's criteria for the diagnosis of infective endocarditis, were encountered. ⋯ All 6 isolates were sensitive to penicillin G (MIC 0.008-0.064 microg/mL), cefalothin, erythromycin, clindamycin, and vancomycin. Accurate identification to the species level, by 16S rRNA gene sequencing, in cases of bacteremia caused by members of the "S. milleri group", would have direct implication on the underlying disease process, hence guiding diagnosis and treatment. Infective endocarditis should be actively looked for in cases of monomicrobial S. anginosus bacteremia, especially if the organism is recovered in multiple blood cultures.
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Diagn. Microbiol. Infect. Dis. · Feb 2004
Pharmacokinetic/pharmacodynamic modeling can help guide targeted antimicrobial therapy for nosocomial gram-negative infections in critically ill patients.
Critically ill patients have altered pharmacokinetics (PK) that need to be considered when choosing and dosing antibiotics. We conducted a prospective, observational study to assess clinical and microbiologic response rates in 19 critically ill patients with nosocomial Gram-negative infections. ⋯ With targeted antimicrobial therapy adjusted to achieve an optimal PD profile, 17/19 (89%) patients had a clinical cure or improvement and 16/19 (84%) had either microbiologic eradication or presumed eradication. Modeling PD in these critically ill patients resulted in good clinical and microbiologic outcomes.