The current article summarizes recent changes in nomenclature for fungi of medical importance published in the years 2018 to 2019, including new species and revised names for existing ones. Many of ...the revised names have been widely adopted without further discussion. However, those that concern common pathogens of humans may take longer to achieve general usage, with new and current names reported together to engender increasing familiarity with the correct taxonomic classification.
Candida africana is a pathogenic species within the Candida albicans species complex. Due to the limited knowledge concerning its prevalence and antifungal susceptibility profiles, a comprehensive ...study is overdue. Accordingly, we performed a search of the electronic databases for literature published in the English language between 1 January 2001 and 21 March 2020. Citations were screened, relevant articles were identified, and data were extracted to determine overall intra-C. albicans complex prevalence, geographical distribution, and antifungal susceptibility profiles for C. africana. From a total of 366 articles, 41 were eligible for inclusion in this study. Our results showed that C. africana has a worldwide distribution. The pooled intra-C. albicans complex prevalence of C. africana was 1.67% (95% CI 0.98-2.49). Prevalence data were available for 11 countries from 4 continents. Iran (3.02%, 95%CI 1.51-4.92) and Honduras (3.03%, 95% CI 0.83-10.39) had the highest values and Malaysia (0%) had the lowest prevalence. Vaginal specimens were the most common source of C. africana (92.81%; 155 out of 167 isolates with available data). However, this species has also been isolated from cases of balanitis, from patients with oral lesions, and from respiratory, urine, and cutaneous samples. Data concerning the susceptibility of C. africana to 16 antifungal drugs were available in the literature. Generally, the minimum inhibitory concentrations of antifungal drugs against this species were low. In conclusion, C. africana demonstrates geographical variation in prevalence and high susceptibility to antifungal drugs. However, due to the relative scarcity of existing data concerning this species, further studies will be required to establish more firm conclusions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The current article summarizes recent changes in nomenclature for fungi of medical importance published in the years 2020 to 2021, including new species and revised names for existing ones. Many of ...the revised names have been widely adopted without further discussion. However, those that concern common pathogens of humans may take longer to achieve general usage, with new and current names reported together to engender increasing familiarity with the correct taxonomic classification.
Abstract
Candida auris has recently emerged as a serious nosocomial health risk, with widespread outbreaks in numerous hospitals worldwide and the existence of geographic region-specific discrete ...clonal lineages. Here we have compared the rDNA sequences of 24 isolates of Candida auris from 14 different hospital centers in the United Kingdom with those of strains from different international origins present in the public sequence databases. Here we show that UK isolates of C. auris fall into three well-supported clades corresponding to lineages that have previously been reported from India, Malaysia and Kuwait, Japan and Korea, and South Africa, respectively.
is a serious nosocomial health risk, with widespread outbreaks occurring in hospitals worldwide. Sequence analyses of outbreak isolates revealed that
has simultaneously emerged as four distinct ...continentally restricted clonal lineages. We previously reported multiple independent introductions of
isolates from at least three of these lineages (the Southern Asia, South African, and Japanese/Korean lineages) into hospitals across the United Kingdom and that isolates circulating in the United Kingdom displayed two different cell phenotypes which correlated with differences in virulence in
wax moths. Here, we compared the phenotypic characteristics and antifungal susceptibilities of isolates representative of the three geographic clades circulating in the United Kingdom. Isolates of the South African and Japanese/Korean lineages, but not those of the Southern Asian lineage, grew well on media containing actidione. However, unlike Southern Asian lineage isolates, they were unable to produce even rudimentary pseudohyphae in culture. Importantly, although all isolates were fluconazole resistant
, fluconazole and voriconazole exhibited significantly higher MICs against isolates of the South African lineage than against isolates of the Southern Asian lineage. A similar trend was seen with minimum fungicidal concentrations (MFCs), with higher MFCs of the triazole antifungal agents being seen for the South African lineage isolates. Finally, the formation of large cellular aggregates was seen only with isolates of the South African and Japanese/Korean lineages, which correlates with the reduced virulence observed previously in
wax moths inoculated with such isolates. Intriguingly, aggregation could be reversibly induced in isolates of the Southern Asian lineage by exposure to triazole and echinocandin antifungals but not by exposure to amphotericin B or flucytosine.
...C. auris cases in England predominantly appeared in specialist hospitals that clustered around the principal entry points of people traveling to and from endemic areas, which, to an extent, also ...reflects the geographical spread of immigrant communities. Before the end of 2017, laboratories that employed matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for yeast identification using the Bruker platform were theoretically able to adequately identify this emerging pathogen. ...the MRL has recently investigated the utility of a novel chromogenic agar (CHROMagar Candida Plus) developed specifically to facilitate detection and identification of C. auris. UK Public Health responses to C. auris Following the identification of 2 English hospitals with the first heathcare-associated outbreaks of C. auris in Europe 6,10, in 2016, a national incident management team (IMT) was convened by PHE in order to develop a consistent national response to this emerging nosocomial pathogen.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
COVID-19-associated pulmonary aspergillosis (CAPA) was recently reported as a potential infective complication affecting critically ill patients with acute respiratory distress syndrome following ...severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with incidence rates varying from 8 to 33% depending on the study. However, definitive diagnosis of CAPA is challenging. Standardized diagnostic algorithms and definitions are lacking, clinicians are reticent to perform aerosol-generating bronchoalveolar lavages for galactomannan testing and microscopic and cultural examination, and questions surround the diagnostic sensitivity of different serum biomarkers. Between 11 March and 14 July 2020, the UK National Mycology Reference Laboratory received 1,267 serum and respiratory samples from 719 critically ill UK patients with COVID-19 and suspected pulmonary aspergillosis. The laboratory also received 46 isolates of
from COVID-19 patients (including three that exhibited environmental triazole resistance). Diagnostic tests performed included 1,000 (1-3)-β-d-glucan and 516 galactomannan tests on serum samples. The results of this extensive testing are presented here. For a subset of 61 patients, respiratory specimens (bronchoalveolar lavage specimens, tracheal aspirates, and sputum samples) in addition to serum samples were submitted and subjected to galactomannan testing,
-specific PCR, and microscopy and culture. The incidence of probable/proven and possible CAPA in this subset of patients was approximately 5% and 15%, respectively. Overall, our results highlight the challenges in biomarker-driven diagnosis of CAPA, especially when only limited clinical samples are available for testing, and the importance of a multimodal diagnostic approach involving regular and repeat testing of both serum and respiratory samples.
Numerous fungal species of medical importance have been recently subjected to and will likely continue to undergo nomenclatural changes as a result of the application of molecular approaches to ...fungal classification together with abandonment of dual nomenclature. Here, we summarize those changes affecting key groups of fungi of medical importance, explaining the mycological (taxonomic) rationale that underpinned the changes and the clinical relevance/importance (where such exists) of the key nomenclatural revisions. Potential mechanisms to mitigate unnecessary taxonomic instability are suggested, together with approaches to raise awareness of important changes to minimize potential clinical confusion.
Candida auris, first described in 2009, has since emerged as an important, multidrug-resistant, nosocomial agent of candidemia, with large outbreaks reported worldwide and high mortality rates ...associated with therapeutic failure. The current study employed C. auris isolates from a variety of centers in the United Kingdom to evaluate the pathogenicity of this emerging pathogen compared to that of other common pathogenic yeast species in the invertebrate Galleria mellonella infection model. We showed that C. auris isolates differ in their growth characteristics in vitro, with a proportion of isolates failing to release daughter cells after budding, resulting in the formation of large aggregates of cells that cannot be physically disrupted. Our results also demonstrate strain-specific differences in the behavior of C. auris in G. mellonella, with the aggregate-forming isolates exhibiting significantly less pathogenicity than their nonaggregating counterparts. Importantly, the nonaggregating isolates exhibited pathogenicity comparable to that of C. albicans, which is currently accepted as the most pathogenic member of the genus, despite the fact that C. auris isolates do not produce hyphae and produce only rudimentary pseudohyphae either in vitro or in G. mellonella. IMPORTANCE The incidence of invasive candidiasis, which includes candidemia and deep tissue infections, continues to rise and is associated with considerable mortality rates. Candida albicans remains the most common cause of invasive candidiasis, although the prevalence of non-albicans species has increased over recent years. Since its first description in 2009, Candida auris has emerged as a serious nosocomial health risk, with widespread outbreaks in numerous hospitals worldwide. However, despite receiving considerable attention, little is known concerning the pathogenicity of this emerging fungal pathogen. Here, using the Galleria mellonella insect systemic infection model, we show strain-specific differences in the virulence of C. auris, with the most virulent isolates exhibiting pathogenicity comparable to that of C. albicans, which is currently accepted as the most pathogenic member of the genus.
PDF
