Impact of Erg11 Amino Acid Substitutions Identified in Candida auris Clade III Isolates on Triazole Drug Susceptibility.

ERG11 sequencing of 28 Candida auris clade III isolates revealed the presence of concomitant V125A and F126L substitutions. Heterologous expression of Erg11-V125A/F126L in Saccharomyces cerevisiae led to reduced fluconazole and voriconazole susceptibilities. Generation of single substitution gene variants through site-directed mutagenesis uncovered that F126L primarily contributes to the elevated triazole MICs. A similar yet diminished pattern of reduced susceptibility was observed with the long-tailed triazoles posaconazole and itraconazole for the V125A/F126L, F126L, Y132F, and K143R alleles.

Fungal yield from sterile specimens.

Clinicians may not request fungal culture when it is indicated. For sterile specimens without a specific request for fungal culture, in addition to bacteriology media, we routinely incubated a Sabouraud dextrose agar (SAB) plate for 4 weeks. From 44635 sterile specimens from years 2011 to 2016, 2722 (6.1%) had fungal request. Fungi were identified from 1037 (2.3%) specimens, 292 (0.6%) from specimens with specific fungal request, 574 (1.3%) from bacteriology media, and 171 (0.4%) solely from SAB plate (of 171, 77 were deemed clinically significant and 55 were treated). Relying on request for fungal studies from sterile specimens underdiagnosed fungal infection. Routine fungal culture had a modest incremental yield at a moderately high cost. LAY SUMMARY: Routine fungal culture of sterile specimens had a modest incremental yield to routine bacteriology culture and specific fungal request at a moderately high financial cost.

Candida auris Sternal Osteomyelitis in a Man from Kenya Visiting Australia, 2015.

In Australia in 2015, Candida auris sternal osteomyelitis was diagnosed in a 65-year-old man with a history of intensive care treatment in Kenya in 2012 and without a history of cardiac surgery. The isolate was South Africa clade III. Clinicians should note that C. auris can cause low-grade disease years after colonization.

Cutaneous mucormycosis and motor vehicle accidents: Findings from an Australian case series.

Cutaneous disease is the third most frequent manifestation of mucormycosis. The clinical manifestations of and subsequent mortality due to cutaneous mucormycosis are dependent on the mode of acquisition and the host immune status. Here, we describe the epidemiology, clinical presentation, microbiology, and outcomes of 16 cutaneous mucormycosis infections managed in an Australian tertiary hospital over a 15-year period. The proportion with localized (56%), deep (38%), and disseminated (6%) cutaneous disease as well as the overall mortality (25%) were consistent with findings reported in the published literature. Two novel forms of hospital-acquired infection were reported following a sacral pressure sore and insertion of a foreign body during a bone graft procedure. The majority of patients were immunocompetent (75%) and/or suffered trauma (56%) with associated environmental contamination. A novel finding was that motor vehicle accidents (MVAs) accounted for 78% of all trauma-related cases, suggesting MVAs should receive greater recognition as a potential precipitant of cutaneous mucormycosis. Aggressive decontamination and debridement of devitalized tissue following trauma is therefore likely to play an important role in the prevention of this rare but potentially devastating infection.

Attitudes of Australasian Clinicians and Laboratory Staff to Changing Fungal Nomenclature: Has Mycological Correctness Really Gone Mad?

Fungal nomenclature changes have been a regular occurrence in recent years, eliciting heated debate on whether such changes will confuse clinicians and harm patients. We conducted surveys of Australasian laboratory staff and clinicians to assess attitudes, practices, and concerns regarding nomenclatural change. The majority of respondents to both surveys were aware of fungal nomenclatural changes (93.5% laboratories, 79.7% clinicians); 72.8% of laboratories had already implemented nomenclature changes, and 68.7% of clinicians recalled receiving at least one laboratory report utilizing updated fungal nomenclature. The vast majority of clinicians (94%) both within and outside of infection specialties supported laboratories reporting updated species names with inclusion of the previous species name. The importance of including the previous name on reports was demonstrated by 73.3% of clinicians viewing "Nakaseomyces glabrata (formerly Candida glabrata)" as clinically significant, versus only 38.2% viewing "Pichia kudriavzeveii" as significant in the absence of its former name. When asked about reporting practices, 73.9% of laboratories would report a Candida krusei isolate as "Pichia kudriavzeveii (formerly Candida krusei)," with the rest reporting as "Candida krusei" (21.7%) or "Pichia kudriavzeveii" (1.1%) without further explanation. Laboratory concerns included clinicians being confused by reports, commonly used identification platforms continuing to use superseded species names, education of staff, and delays in updating species codes in laboratory information systems. Adopting fungal name changes appears to be well supported by laboratories and clinicians in Australia and New Zealand, and can be achieved safely and unambiguously provided the former name is included on reports. IMPORTANCE Recent changes in fungal species names have been contentious, eliciting heated debate on social media. Despite available recommendations on adapting to the changes, concerns include clinicians dismissing pathogens as contaminants with patient harm as a result, and disruption of the literature. Such concerns are understandable, but are not supported by evidence and may represent a vocal minority. This survey of Australasian laboratories and clinicians assesses attitudes and practices relating to changes in fungal nomenclature and found that there is overwhelming support for adopting nomenclature changes.

Cystic Fibrosis Clinical Isolates of Aspergillus fumigatus Induce Similar Muco-inflammatory Responses in Primary Airway Epithelial Cells.

Aspergillus is increasingly associated with lung inflammation and mucus plugging in early cystic fibrosis (CF) disease during which conidia burden is low and strains appear to be highly diverse. It is unknown whether clinical Aspergillus strains vary in their capacity to induce epithelial inflammation and mucus production. We tested the hypothesis that individual colonising strains of Aspergillus fumigatus would induce different responses. Ten paediatric CF Aspergillus isolates were compared along with two systemically invasive clinical isolates and an ATCC reference strain. Isolates were first characterised by ITS gene sequencing and screened for antifungal susceptibility. Three clusters (A-C) of Aspergillus isolates were identified by ITS. Antifungal susceptibility was variable, particularly for itraconazole. Submerged CF and non-CF monolayers as well as differentiated primary airway epithelial cell cultures were incubated with conidia for 24 h to allow germination. None of the clinical isolates were found to significantly differ from one another in either IL-6 or IL-8 release or gene expression of secretory mucins. Clinical Aspergillus isolates appear to be largely homogenous in their mucostimulatory and immunostimulatory capacities and, therefore, only the antifungal resistance characteristics are likely to be clinically important.

Investigation of a Lomentospora prolificans case cluster with whole genome sequencing.

Lomentospora prolificans has caused outbreaks in immunocompromised patients. We performed whole genome sequencing (WGS) on 4 L. prolificans isolates from infections occurring during an 8-month period in the haematology unit at Hospital 1., and 2 isolates from unrelated infections at Hospital 2., showing a high number of mutational differences (>10,000 single nucleotide polymorphisms) between L. prolificans isolates from Hospital 1. Novel typing of isolates by WGS did not demonstrate a single causative strain.

Contact lens associated keratitis due to Tintelnotia destructans.

We report the first case of Tintelnotia destructans associated keratitis in a contact lens wearer in Australia. Corneal scrape showed fungal elements on direct microscopy leading to a prompt diagnosis of fungal keratitis and early topical and systemic antifungal therapy. The isolate was eventually identified by ITS gene sequencing. This case highlights the importance of accurate identification and antifungal susceptibility testing for the management of fungal keratitis.

Tracing the Evolutionary History and Global Expansion of Candida auris Using Population Genomic Analyses.

Candida auris has emerged globally as a multidrug-resistant yeast that can spread via nosocomial transmission. An initial phylogenetic study of isolates from Japan, India, Pakistan, South Africa, and Venezuela revealed four populations (clades I, II, III, and IV) corresponding to these geographic regions. Since this description, C. auris has been reported in more than 30 additional countries. To trace this global emergence, we compared the genomes of 304 C. auris isolates from 19 countries on six continents. We found that four predominant clades persist across wide geographic locations. We observed phylogeographic mixing in most clades; clade IV, with isolates mainly from South America, demonstrated the strongest phylogeographic substructure. C. auris isolates from two clades with opposite mating types were detected contemporaneously in a single health care facility in Kenya. We estimated a Bayesian molecular clock phylogeny and dated the origin of each clade within the last 360 years; outbreak-causing clusters from clades I, III, and IV originated 36 to 38 years ago. We observed high rates of antifungal resistance in clade I, including four isolates resistant to all three major classes of antifungals. Mutations that contribute to resistance varied between the clades, with Y132F in ERG11 as the most widespread mutation associated with azole resistance and S639P in FKS1 for echinocandin resistance. Copy number variants in ERG11 predominantly appeared in clade III and were associated with fluconazole resistance. These results provide a global context for the phylogeography, population structure, and mechanisms associated with antifungal resistance in C. aurisIMPORTANCE In less than a decade, C. auris has emerged in health care settings worldwide; this species is capable of colonizing skin and causing outbreaks of invasive candidiasis. In contrast to other Candida species, C. auris is unique in its ability to spread via nosocomial transmission and its high rates of drug resistance. As part of the public health response, whole-genome sequencing has played a major role in characterizing transmission dynamics and detecting new C. auris introductions. Through a global collaboration, we assessed genome evolution of isolates of C. auris from 19 countries. Here, we described estimated timing of the expansion of each C. auris clade and of fluconazole resistance, characterized discrete phylogeographic population structure of each clade, and compared genome data to sensitivity measurements to describe how antifungal resistance mechanisms vary across the population. These efforts are critical for a sustained, robust public health response that effectively utilizes molecular epidemiology.

Epidemiology and antifungal susceptibility patterns of candidemia from a tertiary centre in Western Australia.

Candidemia is a common invasive fungal infection with a high mortality rate. We performed a retrospective audit of candidemia at a tertiary centre in Western Australia, 2005-2014. There were 167 episodes of candidemia due to 173 isolates of Candida. Candida albicans (40.5%), Candida glabrata complex (30.6%), Candida parapsilosis complex (14.4%) were the most common species causing candidemia across the study. Of the tested isolates, 17.7% (11/62) were non-susceptible to fluconazole and 13.6% (9/66) non-susceptible to caspofungin. 22.8% (8/35) C. glabrata complex were fluconazole resistant and 17.1% (6/35) were non-susceptible to caspofungin. Candida glabrata complex was more common in the latter time period, but there were no susceptibility changes over time. In our setting, the prevalence of C. glabrata complex and antifungal non-susceptibility is high, and the prevalence of C. glabrata complex is increasing.

Rapid identification of fungal pathogens in BacT/ALERT, BACTEC, and BBL MGIT media using polymerase chain reaction and DNA sequencing of the internal transcribed spacer regions.

We report a direct polymerase chain reaction/sequence (d-PCRS)-based method for the rapid identification of clinically significant fungi from 5 different types of commercial broth enrichment media inoculated with clinical specimens. Media including BacT/ALERT FA (BioMérieux, Marcy l'Etoile, France) (n = 87), BACTEC Plus Aerobic/F (Becton Dickinson, Microbiology Systems, Sparks, MD) (n = 16), BACTEC Peds Plus/F (Becton Dickinson) (n = 15), BACTEC Lytic/10 Anaerobic/F (Becton Dickinson) (n = 11) bottles, and BBL MGIT (Becton Dickinson) (n = 11) were inoculated with specimens from 138 patients. A universal DNA extraction method was used combining a novel pretreatment step to remove PCR inhibitors with a column-based DNA extraction kit. Target sequences in the noncoding internal transcribed spacer regions of the rRNA gene were amplified by PCR and sequenced using a rapid (24 h) automated capillary electrophoresis system. Using sequence alignment software, fungi were identified by sequence similarity with sequences derived from isolates identified by upper-level reference laboratories or isolates defined as ex-type strains. We identified Candida albicans (n = 14), Candida parapsilosis (n = 8), Candida glabrata (n = 7), Candida krusei (n = 2), Scedosporium prolificans (n = 4), and 1 each of Candida orthopsilosis, Candida dubliniensis, Candida kefyr, Candida tropicalis, Candida guilliermondii, Saccharomyces cerevisiae, Cryptococcus neoformans, Aspergillus fumigatus, Histoplasma capsulatum, and Malassezia pachydermatis by d-PCRS analysis. All d-PCRS identifications from positive broths were in agreement with the final species identification of the isolates grown from subculture. Earlier identification of fungi using d-PCRS may facilitate prompt and more appropriate antifungal therapy.