Antifungal susceptibility of the Aspergillus species by Etest and CLSI reference methods

Because resistance to antifungal drugs is seen in patients, susceptibility testing of these drugs aids in choosing the appropriate drug and respective epidemiology. This study has investigated and compared susceptibility patterns of the Aspergillus species sisolated from patients by the Clinical and Laboratory Standards Institute [CLSI] reference broth microdilution [MD] assay and Etest method. The minimum inhibitory concentrations [MICs] of various antifungal agents [amphotericin B, ketoconazole, itraconazole, and voriconazole] for 108 Aspergillus species isolated from patients were determined by CLSI M38-A broth MD and Etest. The isolates were obtained from clinical samples that included tissues, sputum, bronchoalveolar lavage, abdominal tap, and cerebrospinal fluid. As revealed by the MD method, 63.9% of the isolates were sensitive to amphotericin B and 36.1% were resistant. Etest revealed that 61.1% were sensitive to amphotericin B and 38.9% were resistant. As for ketoconazole, 108 isolates [100%] were shown to be sensitive through the MD method; while the Etest revealedan 88.9% sensitivity and 11.1% were resistant. All species were susceptible to voriconazole, according to both methods. The measure of agreement [Kappa Index] for these three drugs was satisfactory [>/= 0.6]. According to the MD method, 69.4% of the species were susceptible to itraconazole, whereas 30.6% were not. For this drug, the Etest showed 86.1% susceptible and 13.9% resistant. Voriconazole was the most effective agent against isolates. Using RPMI agar, we found the Etest to be helpful, readily available, and easy to use for determining invitro susceptibilities of Aspergillus species to voriconazole, amphotericin B, ketoconazole, and itraconazole in the region of this study

Assessment of a real-time PCR method to detect human non-cryptococcal fungal meningitis

The signs and symptoms associated with fungal meningitis are similar to those seen with more common bacterial infections. In this study, we investigate whether Aspergillus or Candida DMA can be detected in cerebrospinal fluid [CSF] samples from patients suspected of fungal meningitis using real-time PCR assay. From April 2007 to November 2009, we evaluated CSF samples and sera from patients with risk factors for cerebral fungal meningitis in Nemazi Hospital, Shiraz University of Medical Sciences, Iran, by real-time PCR assay and routine mycological studies [direct microscopy examination and culture]. Two CSF and two serum samples from each patient were examined. CSF and serum samples from 38 patients [total: 152] suspected of fungal meningitis were examined. India ink staining and KOH smear were negative for all patients. C. albicans was isolated from two CSF samples. There were ten patients with positive real-time PCR results in their CSF samples: three patients had C. albicans, one with C. glabrata, four with Aspergillus species and two with both C. albicans and Aspergillus species DMA. Four patients had positive serum results for Aspergillus or Candida infections. Considering the findings, it seems that molecular examination can help in the diagnosis of fungal meningitis in patients with clinical and radiological presentations. Further studies should be conducted in other regions and settings to confirm these findings