Diagnostic microbiology and infectious disease
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Diagn. Microbiol. Infect. Dis. · Jul 2014
Multicenter Study Comparative StudyClinical utility of Aspergillus galactomannan and PCR in bronchoalveolar lavage fluid for the diagnosis of invasive pulmonary aspergillosis in patients with haematological malignancies.
Interpretation of Aspergillus galactomannan (GM) and PCR results in bronchoalveolar lavage (BAL) fluid for the diagnosis of invasive pulmonary aspergillosis (IPA) in patients with haematological malignancies requires clarification. A total of 116 patients underwent BAL for investigation of new lung infiltrates: 40% were neutropenic, 68% and 36% were receiving mould-active antifungal agents and β-lactam antibiotics. The diagnosis of proven IPA (n = 3), probable IPA (n = 15), and possible invasive fungal disease (IFD, n = 50) was made without inclusion of GM results. ⋯ Both tests had excellent negative predictive values (85-90%), supporting their utility in excluding IPA. The use of BAL GM and PCR results increased the certainty of Aspergillus aetiology in 7 probable IPA cases where fungal hyphae were detected in respiratory samples by microscopy, and upgraded 24 patients from possible IFD to probable IPA. Use of BAL GM and PCR improves the diagnosis of IPA.
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Diagn. Microbiol. Infect. Dis. · Jun 2014
Review Case ReportsSuccessful treatment of osseous blastomycosis without pulmonary or disseminated disease and review of the literature.
Blastomycosis commonly occurs following inhalation of Blastomyces dermatitidis conidia causing a pulmonary infection and can disseminate to extrapulmonary sites. Osseous involvement primarily results from hematogenous spread, but in rare cases, direct inoculation can occur. We describe a case of osseous blastomycosis without pulmonary or disseminated disease successfully treated with posaconazole.
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Diagn. Microbiol. Infect. Dis. · Jun 2014
Association of clinical and demographic factors in invasive candidiasis caused by fluconazole-resistant Candida species: a study in 15 hospitals, Medellín, Colombia 2010-2011.
Candida is the most important agent of fungal infections. Several risk factors have been described associated with invasive infection by fluconazole-resistant Candida spp. A prospective cross-sectional study with case-control analysis was conducted. ⋯ Neutropenia (adjusted odds ratio [aOR] 6.5, 95% confidence interval [CI] 1.0-43.1), antifungal exposure (aOR 5.1, 95% CI 2.3-11.2), and antituberculosis therapy (aOR 7.7, 95% CI 1.4-43.2) were associated to fluconazole resistance. Susceptibility results are useful to guide the selection of empiric antifungal treatment and the design of local therapeutic guidelines. Previous antifungal exposure suggests possible resistance to fluconazole, pointing towards the selection of a different class of antifungal agents.
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Diagn. Microbiol. Infect. Dis. · Jun 2014
Rapid simultaneous identification and quantitation of Staphylococcus aureus and Pseudomonas aeruginosa directly from bronchoalveolar lavage specimens using automated microscopy.
Diagnosis of ventilator-assisted pneumonia (VAP) requires pathogen quantitation of respiratory samples. Current quantitative culture methods require overnight growth, and pathogen identification requires an additional step. Automated microscopy can perform rapid simultaneous identification and quantitation of live, surface-immobilized bacteria extracted directly from patient specimens using image data collected over 3 h. ⋯ Microscopy identified 9/9 S. aureus and 7/7 P. aeruginosa in all specimens with content above the VAP diagnostic threshold. Concordance for specimens containing targets above the diagnostic threshold was 13/16, with concordance for sub-diagnostic content of 86/90. Results demonstrated that automated microscopy had higher precision than 1 μL loop culture (range ~0.55 log versus ≥1 log), with a dynamic range of ~4 logs (~10(3) to 10(6) CFU/mL).
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Diagn. Microbiol. Infect. Dis. · Jun 2014
Comparative StudyComparison of EUCAST and CLSI broth microdilution methods for the susceptibility testing of 10 systemically active antifungal agents when tested against Candida spp.
The antifungal broth microdilution (BMD) method of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) was compared with Clinical and Laboratory Standards Institute (CLSI) BMD method M27-A3 for amphotericin B, flucytosine, anidulafungin, caspofungin, micafungin, fluconazole, isavuconazole, itraconazole, posaconazole, and voriconazole susceptibility testing of 357 isolates of Candida. The isolates were selected from global surveillance collections to represent both wild-type (WT) and non-WT MIC results for the azoles (12% of fluconazole and voriconazole results were non-WT) and the echinocandins (6% of anidulafungin and micafungin results were non-WT). The study collection included 114 isolates of Candida albicans, 73 of C. glabrata, 76 of C. parapsilosis, 60 of C. tropicalis, and 34 of C. krusei. ⋯ Problem areas with low EA or CA include testing of amphotericin B, anidulafungin, and isavuconazole against C. glabrata, itraconazole, and posaconazole against most species, and caspofungin against C. parapsilosis, C. tropicalis, and C. krusei. We confirm high level EA and CA (>90%) between the 2 methods for testing fluconazole, voriconazole, and micafungin against all 5 species. The results indicate that the EUCAST and CLSI methods produce comparable results for testing the systemically active antifungal agents against the 5 most common species of Candida; however, there are several areas where additional steps toward harmonization are warranted.