Journal of clinical microbiology
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J. Clin. Microbiol. · Apr 2013
The value of combining blood culture and SeptiFast data for predicting complicated bloodstream infections caused by Gram-positive bacteria or Candida species.
Management of complicated bloodstream infections requires more aggressive treatment than uncomplicated bloodstream infections. We assessed the value of follow-up blood culture in bloodstream infections caused by Staphylococcus aureus, Enterococcus spp., Streptococcus spp., and Candida spp. and studied the value of persistence of DNA in blood (using SeptiFast) for predicting complicated bloodstream infections. Patients with bloodstream infections caused by these microorganisms were enrolled prospectively. ⋯ With a cutoff of 7, the negative predictive value for complicated bloodstream infection was 96.6%. Patients with a positive SeptiFast result between days 3 and 7 after a positive blood culture have an almost 8-fold-higher risk of developing complicated bloodstream infections. A score combining clinical data with the SeptiFast result may improve the exclusion of complicated bloodstream infections.
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J. Clin. Microbiol. · Apr 2013
Case ReportsCatalase-negative Staphylococcus lugdunensis strain with a novel point mutation in the catalase gene isolated from a patient with chronic suppurative otitis media.
This report describes the results of the sequence analysis of a methicillin-susceptible strain of catalase-negative Staphylococcus lugdunensis. Molecular characterization of the deduced sequence revealed a novel point mutation in the catalase gene. To our knowledge, this is the first report of a catalase-negative S. lugdunensis strain, although catalase-negative isolates of Staphylococcus aureus and Staphylococcus epidermidis have been previously reported.
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J. Clin. Microbiol. · Apr 2013
Comparison of (1->3)-β-D-glucan, mannan/anti-mannan antibodies, and Cand-Tec Candida antigen as serum biomarkers for candidemia.
We conducted a case-control study using the Fungitell assay, the novel Platelia Candida Antigen (Ag) Plus and Candida Antibody (Ab) Plus assays, and the Cand-Tec latex agglutination test to evaluate the usefulness of (1→3)-β-D-glucan (BDG), mannan antigen with/without anti-mannan antibody, and Cand-Tec Candida antigen measurement for the diagnosis of candidemia. A total of 56 patients fulfilled the inclusion criteria and were enrolled. One hundred patients with bacteremia and 100 patients with sterile blood cultures served as negative controls. ⋯ Combining procalcitonin (PCT) with (1→3)-β-D-glucan to increase specificity provided a limited advantage because the benefit of the combination did not outweigh the loss of sensitivity. Our results demonstrate that the Cand-Tec Candida antigen and the mannan antigen plus anti-mannan antibody measurements have unacceptably low sensitivity or specificity. Of the four tests compared, (1→3)-β-D-glucan and mannan antigen are the superior biomarkers, depending on whether a sensitivity-driven or specificity-driven approach is used.
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J. Clin. Microbiol. · Mar 2013
Case ReportsKlebsiella pneumoniae K1 liver abscess and septic endophthalmitis in a U.S. resident.
Klebsiella pneumoniae K1 is a major agent of hepatic abscess with metastatic disease in East Asia, with sporadic reports originating elsewhere. We report a case of abscess complicated by septic endophthalmitis caused by a wzyAKpK1-positive Klebsiella strain in a U. S. resident, raising concern for global emergence.
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J. Clin. Microbiol. · Mar 2013
Quantitative cultures of bronchoscopically obtained specimens should be performed for optimal management of ventilator-associated pneumonia.
Ventilator-associated pneumonia (VAP) is a leading cause of health care-associated infection. It has a high rate of attributed mortality, and this mortality is increased in patients who do not receive appropriate empirical antimicrobial therapy. As a result of the overuse of broad-spectrum antimicrobials such as the carbapenems, strains of Acinetobacter, Enterobacteriaceae, and Pseudomonas aeruginosa susceptible only to polymyxins and tigecycline have emerged as important causes of VAP. ⋯ However, there is no consensus in the clinical microbiology community as to whether these specimens should be cultured quantitatively, using the aforementioned designated bacterial cell count to designate infection, or by a semiquantitative approach. We have asked Vickie Baselski, University of Tennessee Health Science Center, who was the lead author on one of the seminal papers on quantitative BAL fluid culture, to explain why she believes that quantitative BAL fluid cultures are the optimal strategy for VAP diagnosis. We have Stacey Klutts, University of Iowa, to advocate the semiquantitative approach.