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To the Editor: Methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST)398 has become increasingly common in livestock, particularly pigs, in some countries in Europe, such as Spain and Germany (1). In [...]

In this study we compare the capability of amplification fragment-length polymorphism (AFLP) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify and subtype isolates of members of the Candida parapsilosis complex (C. parapsilosis, C. orthopsilosis, C. metapsilosis) and Lodderomyces elongisporus, which cannot be differentiated with biochemical methods. Both techniques correctly identified all isolates included in this study and clustered isolates within the different species. DNA-based and mass spectrum–based dendrograms yielded similar outcomes with regard to phylogenetic distance within C. orthopsilosis and C. parapsilosis species. However, a different clustering was obtained for C. metapsilosis for which AFLP was highly effective in differentiating. While MALDI-TOF MS was found to be a reliable method for species-level identification, further studies are required to assess its value as a fungal typing tool. [ABSTRACT FROM PUBLISHER]

Trichosporon urinary tract infection (UTI) is an unusual emerging infection, caused mostly by Trichosporon asahii, described especially in hospitalized patients. To date the interpretation and management of Trichosporon positive urinary culture remains a diagnostic and therapeutic dilemma for which there are no precise indications, and the challenge can be even more complicated in comorbid frail elderly patients. Triazoles are known to be the most effective antifungal drugs but can raise concerns about pharmacological interaction. We report a case of Trichosporon asahii nosocomial UTI in an elderly patient.

Fungal infections have increased significantly in the last few years, and their outcomes are in part complicated by the emergence of antifungal drug-resistant pathogens. Together with Candida species, the mould Aspergillus fumigatus is one of the most prevalent organisms to cause invasive fungal disease. The molecular detection of (tri)azole resistance in both Candida and Aspergillus species may represent a useful means of monitoring the incidence of clinical isolates with antifungal resistance-associated gene alterations. Here, we describe molecular methods that have been developed to allow for accurate detection of azole-resistant isolates among C. glabrata and A. fumigatus fungal species.

In the last years, life-threatening fungal diseases have increased significantly, due to the rising number of human individuals susceptible to fungal infections, which are in part complicated by the emergence of antifungal drug-resistant pathogens. Among yeasts, Candida albicans and Candida glabrata are the most common organisms responsible for invasive fungal diseases. The molecular detection of echinocandin resistance in Candida species may represent a useful means of monitoring the incidence of clinical isolates with antifungal resistance-associated gene alterations. Here, we describe the current methods that enable researchers and/or clinical microbiologists to accurately detect echinocandin-resistant isolates of C. albicans and C. glabrata.

Aspergillus species are the cause of invasive mold infections in immunocompromised patients: Aspergillus fumigatus, A. flavus and A. terreus account for most cases of invasive aspergillosis (IA). As certain species are associated with higher mortality and vary in their resistance to antifungal therapy, diagnosis requires increasingly rapid molecular methods that enable sensitive detection and species discrimination. We have developed PCR and Multiplex PCR assays for the detection of six medically important Aspergillus spp. species DNA in bronchoalveolar lavage (BAL) specimens from hematology and intensive care unit (ICU) patients at risk of IA, using different species and genus-specific PCR primers, selected within the SCW4 gene, encoding a cell wall glucanase of A. fumigatus, similar to mannoprotein Mp65 of Candida albicans. The genus-specific PCR primers were able to amplify only Aspergillus DNAs but not that belonging to other fungal genera tested. The species-specific PCR primers allowed differentiation of each Aspergillus species by the amplicon length produced. The methods described in this study are rapid (less than 4 h), reproducible, simple and specific and demonstrate potential application in the clinical laboratory.

Emerging fungal pathogens, such as Geotrichum capitatum, are often associated with poor prognosis and represent a new challenge in modern medicine. Invasive Geotrichum capitatum infection is rare and has been reported exclusively in patients who showed signs of severe immunodeficiency, particularly those affected by haematological malignancies. The optimal therapy against systemic geotricosis has not yet been identified due to limited data about its antifungal susceptibility. The use of several therapeutic strategies and the low number of cases treated does not allow identification of specific therapeutic protocols. Furthermore, in spite of antifungal therapy, mortality rates reach very high levels. We report a case of systemic Geotrichum capitatum infection in a 78-year-old male treated with salvage therapy after acute myeloid leukaemia (AML) relapse. Geotrichum capitatum was isolated from his blood culture and identified by using Vitek 2 and Maldi time-of-flight system (MALDI-TOF). The infection was unsuccessfully treated, despite in vitro susceptibility, with micafungin and liposomal amphotericin B.

In this study we compare the capability of amplification fragment-length polymorphism (AFLP) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify and subtype isolates of members of the Candida parapsilosis complex (C. parapsilosis, C. orthopsilosis, C. metapsilosis) and Lodderomyces elongisporus, which cannot be differentiated with biochemical methods. Both techniques correctly identified all isolates included in this study and clustered isolates within the different species. DNA-based and mass spectrum-based dendrograms yielded similar outcomes with regard to phylogenetic distance within C. orthopsilosis and C. parapsilosis species. However, a different clustering was obtained for C. metapsilosis for which AFLP was highly effective in differentiating. While MALDI-TOF MS was found to be a reliable method for species-level identification, further studies are required to assess its value as a fungal typing tool.