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Worldwide emergence of azole-resistant Aspergillus fumigatus since the late 2000s threatens human health (1). Azole resistance in A. fumigatus might develop during patient therapy with medical azoles or through exposure [...]

Background: Epidemiological knowledge is important to guide antifungal therapy. Objective: This multicentre study aimed to investigate the species distribution and antifungal susceptibility of Aspergillus isolates in Taiwan. Method: Four hundred and ninety‐two clinical Aspergillus isolates, collected during 2016–2020, were identified by calmodulin sequencing and tested for antifungal susceptibility using CLSI M38‐A3. The Cyp51A sequences of azole‐resistant Aspergillus fumigatus and Aspergillus flavus isolates were analysed. Results: This collection comprised 30 species from eight Aspergillus sections—Flavi (33.5%), Nigri (26.0%), Fumigati (24.2%), Terrei (10.0%), Nidulantes (5.1%), Circumdati (0.8%), Restricti (0.2%) and Aspergillus (0.2%). Sections Fumigati, Flavi and Terrei were primarily represented by A. fumigatus (99.2%), A. flavus (95.8%) and A. terreus (100%), respectively. Section Nigri comprised nine species, mostly A. welwitschiae (60.2%), A. niger (12.5%), A. brunneoviolaceus (10.9%) and A. tubingensis (10.2%). A. fumigatus (39.6%) and A. flavus (26.4%) predominated among 53 isolates from lower respiratory samples, whereas section Nigri species (46.2%) and A. terreus (29.2%) predominated among 65 isolates from ear samples. Reduced susceptibility to amphotericin B (minimal inhibitory concentration (MIC) > 1 μg/mL) was noted in A. flavus (7.0%), A. terreus (6.1%), A. nidulans and section Circumdati (A. flocculosus, A. subramanianii and A. westerdijkiae) isolates. Acquired azole resistance was observed in seven A. fumigatus (5.9%), all of which carried TR34/L98H or TR34/L98H/S297T/F495I mutation, and three A. flavus (1.9%), one of which carried G441S mutation. Reduced susceptibility to itraconazole (MIC >1 μg/mL) was noted in 55.5% of section Nigri isolates, mainly in A. welwitschiae, A. niger and A. tubingensis, whereas A. brunneoviolaceus, A. aculeatinus and A. japonicus were hypersusceptible to azoles. Anidulafungin was active against all isolates except for one isolate. Conclusions: This study depicted the molecular epidemiology and species‐specific characteristics of Aspergillus in Taiwan, which aids in appropriate antifungal therapy and underlines the need of speciation and susceptibility testing of disease‐causing Aspergillus. [ABSTRACT FROM AUTHOR]

A study to determine the effect of cAMP-CRP in the regulation of IS2 transposition was conducted. Gel retardation assay was used to identify the binding capability of the cAMP-CRP complex. The results showed that cAMP-CRP binds to the major IS2 promoter. However, the cAMP-CRP complex demonstrated a negative effect on the transcription from the promoter. Results indicating that IS2 is more competently transposed by hosts lacking adenyl cyclase suggest that the cAMP-CRP complex is a negative regulator of IS2.

In a multicenter study, we determined a prevalence rate of 4% for azole-resistant Aspergillus fumigatus in Taiwan. Resistance emerged mainly from the environment (TR34/L98H, TR34/L98H/S297T/F495I, and TR46/Y121F/T289A mutations) but occasionally during azole treatment. A high mortality rate observed for azole-resistant aspergillosis necessitates diagnostic stewardship in healthcare and antifungal stewardship in the environment. [ABSTRACT FROM AUTHOR]

Summary: Emerging azole resistance in Aspergillus fumigatus poses a serious threat to human health. This nationwide surveillance study investigated the prevalence and molecular characteristics of azole‐resistant A. fumigatus environmental isolates in Taiwan, an island country with increasing use of azole fungicides. Of the 2760 air and soil samples screened from 2014 to 2016, 451 A. fumigatus isolates were recovered from 266 samples and 34 isolates from 29 samples displayed resistance to medical azoles (itraconazole, voriconazole or posaconazole). The resistance prevalence was 10.9% and 7.5% in A. fumigatus‐positive samples and isolates respectively. Most (29, 85.3%) azole‐resistant isolates harboured TR34/L98H mutations, which were widely distributed, clustered genetically with clinical isolates, and had growth rates that were similar to those of the wild‐type isolates. Microsatellite genotyping revealed both the global spread of the TR34/L98H isolates and the occurrence of TR34/L98H/S297T/F495I isolates belonging to local microsatellite genotypes. AfuMDR3 and atrF, two efflux transporter genes, were constitutively upregulated in two individual resistant isolates without cyp51A mutations, highlighting their potential roles in azole resistance. These results emphasize the need for periodic environmental surveillance at the molecular level in regions in which azole fungicides are applied, and agricultural fungicide management strategies that generate less selective pressure should be investigated. [ABSTRACT FROM AUTHOR]

Cumulative evidence described the emergence and geographical expansion of azole-resistant A. fumigatus associated with azole treatment failure. To investigate the status of azole resistance in A. fumigatus in Taiwan, we studied 38 A. fumigatus clinical isolates cultivated from 31 patients at two teaching hospitals from 2011 to 2014. Three isolates obtained from respiratory samples of two azole-naïve patients with pulmonary aspergillosis were found to display multi-azole resistance and cross resistance to agricultural azole fungicides, and all carried TR34/L98H mutations in cyp51A gene. The prevalence rates of azole resistance were 7.9% and 6.5% based on isolates and patients respectively. A phylogenetic analysis suggested genetic diversity of the TR34/L98H isolates in Taiwan, including a unique genotype distinct from strains outside Taiwan. The result underlines the emergence of such isolates in Taiwan as well, emphasising the importance of further surveillance for azole-resistant A. fumigatus and implementation of strategies that prevent fungicide-driven resistance selection. [ABSTRACT FROM AUTHOR]

Aeromonas taiwanensis was first described in 2010 on the basis of one clinical wound isolate (strain LMG 24683(T) = A2-50(T) = CECT 7403(T)) from Taiwan. We present here the genome sequence of A. taiwanensis LMG 24683(T), which carries several genes encoding virulence determinants and Ambler class C and D β-lactamases., (Copyright © 2014 Wang et al.)