scholarly journals Trends on Aspergillus Epidemiology—Perspectives from a National Reference Laboratory Surveillance Program

2021 ◽  
Vol 7 (1) ◽  
pp. 28
Author(s):  
Raquel Sabino ◽  
Paulo Gonçalves ◽  
Aryse Martins Melo ◽  
Daniela Simões ◽  
Mariana Oliveira ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Environmental Samples ◽  
Reference Method ◽  
Sensu Stricto ◽  
Antifungal Drugs ◽  
Surveillance Program ◽  
Azole Resistance ◽  
Correct Identification ◽  
Reference Laboratory ◽  
Minimal Inhibitory Concentrations

Identification of Aspergillus to species level is important since sibling species may display variable susceptibilities to multiple antifungal drugs and also because correct identification contributes to improve the knowledge of epidemiological studies. Two retrospective laboratory studies were conducted on Aspergillus surveillance at the Portuguese National Mycology Reference Laboratory. The first, covering the period 2017–2018, aimed to study the molecular epidemiology of 256 Aspergillus isolates obtained from patients with respiratory, subcutaneous, or systemic infections and from environmental samples. The second, using our entire collection of clinical and environmental A. fumigatus isolates (N = 337), collected between 2012 and 2019, aimed to determine the frequency of azole-resistant A. fumigatus isolates. Aspergillus fumigatus sensu stricto was the most frequent species in both clinical and environmental samples. Overall, and considering all Aspergillus sections identified, a high frequency of cryptic species was detected, based on beta-tubulin or calmodulin sequencing (37% in clinical and 51% in environmental isolates). Regarding all Fumigati isolates recovered from 2012–2019, the frequency of cryptic species was 5.3% (18/337), with the identification of A. felis (complex), A. lentulus, A. udagawae, A. hiratsukae, and A. oerlinghauensis. To determine the frequency of azole resistance of A. fumigatus, isolates were screened for azole resistance using azole-agars, and 53 possible resistant isolates were tested by the CLSI microdilution reference method. Nine A. fumigatus sensu stricto and six Fumigati cryptic isolates showed high minimal inhibitory concentrations to itraconazole, voriconazole, and/or posaconazole. Real-time PCR to detect cyp51A mutations and sequencing of cyp51A gene and its promoter were performed. The overall frequency of resistance to azoles in A. fumigatus sensu stricto was 3.0%. With this retrospective analysis, we were able to detect one azole-resistant G54R mutant A. fumigatus environmental isolate, collected in 2015. The TR34/L98H mutation, linked to environmental transmission route of azole resistance, was the most frequently detected mutation (N = 4; 1.4%). Our findings underline the demand for correct identification and susceptibility testing of Aspergillus isolates.

scholarly journals Identification of Cryptic Species of Four Candida Complexes in a Culture Collection

2019 ◽  
Vol 5 (4) ◽  
pp. 117
Author(s):  
Gustavo Fontecha ◽  
Kathy Montes ◽  
Bryan Ortiz ◽  
Celeste Galindo ◽  
Sharleen Braham
Keyword(s):  
Cryptic Species ◽  
Candida Species ◽  
Fungal Infections ◽  
Sensu Stricto ◽  
Culture Collection ◽  
Antifungal Drugs ◽  
Correct Identification ◽  
Candida Spp ◽  
Simple Method ◽  
First Report

Candida spp. are one of the most common causes of fungal infections worldwide. The taxonomy of Candida is controversial and has undergone recent changes due to novel genetically related species. Therefore, some complexes of cryptic species have been proposed. In clinical settings, the correct identification of Candida species is relevant since some species are associated with high resistance to antifungal drugs and increased virulence. This study aimed to identify the species of four Candida complexes (C. albicans, C. glabrata, C. parapsilosis, and C. haemulonii) by molecular methods. This is the first report of six cryptic Candida species in Honduras: C. dubliniensis, C. africana, C. duobushaemulonii, C. orthopsilosis, and C. metapsilosis, and it is also the first report of the allele hwp1-2 of C. albicans sensu stricto. It was not possible to demonstrate the existence of C. auris among the isolates of the C. haemulonii complex. We also propose a simple method based on PCR-RFLP for the discrimination of the multi-resistant pathogen C. auris within the C. haemulonii complex.

scholarly journals Identification of Cryptic Species of Four Candida Complexes in a Culture Collection

2019 ◽  
Author(s):  
Gustavo Fontecha ◽  
Kathy Montes ◽  
Bryan Ortiz ◽  
Celeste Galindo ◽  
Sharleen Braham
Keyword(s):  
Cryptic Species ◽  
Candida Species ◽  
Fungal Infections ◽  
Sensu Stricto ◽  
Culture Collection ◽  
Antifungal Drugs ◽  
Correct Identification ◽  
Candida Spp ◽  
Simple Method ◽  
First Report

Candida spp. are the most common cause of fungal infections worldwide. The taxonomy of Candida is controversial and has undergone recent changes due to novel genetically related species. Therefore, some complexes of cryptic species have been proposed. In clinical settings, the correct identification of Candida species is relevant since some species are associated with high resistance to antifungal drugs and increased virulence. This study aimed to identify the species of four Candida complexes (C. albicans, C. glabrata, C. parapsilosis, and C. haemulonii) by molecular methods. This is the first report of six cryptic Candida species in Honduras: C. dubliniensis, C. africana, C. duobushaemulonii, C. orthopsilosis, and C. metapsilosis, and it is also the first report of the allele hwp1-2 of C. albicans sensu stricto. It was not possible to demonstrate the existence of C. auris among the isolates of the C. haemulonii complex. We also propose a simple method based on PCR-RFLP for the discrimination of the multi-resistant pathogen C. auris within the C. haemulonii complex.

scholarly journals Molecular Identification, Antifungal Susceptibility Testing, and Mechanisms of Azole Resistance in Aspergillus Species Received within a Surveillance Program on Antifungal Resistance in Spain

2019 ◽  
Vol 63 (9) ◽  
Author(s):  
Olga Rivero-Menendez ◽  
Juan Carlos Soto-Debran ◽  
Narda Medina ◽  
Jose Lucio ◽  
Emilia Mellado ◽  
...  
Keyword(s):  
Aspergillus Terreus ◽  
Fungal Infections ◽  
Novel Mutation ◽  
Antifungal Susceptibility ◽  
Resistance Mechanism ◽  
Sensu Stricto ◽  
Antifungal Resistance ◽  
Surveillance Program ◽  
Azole Resistance ◽  
Content Type

ABSTRACT Antifungal resistance is one of the major causes of the increasing mortality rates for fungal infections, especially for those caused by Aspergillus spp. A surveillance program was established in 2014 in the Spanish National Center for Microbiology for tracking resistance in the most prevalent Aspergillus species. A total of 273 samples were included in the study and were initially classified as susceptible or resistant according to EUCAST breakpoints. Several Aspergillus cryptic species were found within the molecularly identified isolates. Cyp51 mutations were characterized for Aspergillus fumigatus, Aspergillus terreus, and Aspergillus flavus sensu stricto strains that were classified as resistant. Three A. fumigatus sensu stricto strains carried the TR34/L98H resistance mechanism, while two harbored G54R substitution and one harbored the TR46/Y121F/T289A mechanism. Seventeen strains had no mutations in cyp51A, with ten of them resistant only to isavuconazole. Three A. terreus sensu stricto strains harbored D344N substitution in cyp51A, one of them combined with M217I, and another carried an A249G novel mutation. Itraconazole-resistant A. flavus sensu stricto strains harbored P220L and H349R alterations in cyp51A and cyp51C, respectively, that need further investigation on their implication in azole resistance.

scholarly journals Regional Differences in Antifungal Susceptibility of the Prevalent Dermatophyte Trichophyton rubrum

2020 ◽  
Vol 186 (1) ◽  
pp. 53-70
Author(s):  
Y. Jiang ◽  
W. Luo ◽  
P. E. Verweij ◽  
Y. Song ◽  
B. Zhang ◽  
...  
Keyword(s):  
Trichophyton Rubrum ◽  
Antifungal Susceptibility ◽  
Sensu Stricto ◽  
Antifungal Drugs ◽  
Primary Therapy ◽  
In Vitro Susceptibility ◽  
Minimal Inhibitory Concentrations ◽  
Upper Limits ◽  
In Vitro Susceptibility Testing

AbstractIn vitro susceptibility testing for Trichophyton rubrum has shown resistance to terbinafine, azoles and amorolfine, locally, but epidemiological cutoffs are not available. In order to assess the appropriateness of current first-line antifungal treatment for T. rubrum in China, we characterized antifungal susceptibility patterns of Chinese T. rubrum strains to nine antifungals and also described the upper limits of wild-type (WT) minimal inhibitory concentrations (MIC) (UL-WT) based on our study and another six studies published during the last decades. Sixty-two clinical isolates originating from seven provinces in China were identified as T. rubrum sensu stricto; all Chinese strains showed low MICs to eight out of nine antifungal drugs. Terbinafine (TBF) showed the lowest MICs of all antifungal classes tested in both the Chinese and global groups, with a 97.5% UL-WT MIC-value of 0.03 mg/L. No non-WT isolates were observed for TBF in China, but were reported in 18.5% of the global group. Our study indicated that TBF was still the most active drug for Chinese T. rubrum isolates, and all strains were within the WT-population. TBF therefore remains recommended for primary therapy to dermatophytosis caused by T. rubrum in China now, but regular surveillance of dermatophytes and antifungal susceptibility is recommended.

scholarly journals Azole resistant Aspergillus fumigatus clinical isolate screening in azole-containing agar plates (EUCAST E.Def 10.1): low impact of plastic trays used and poor performance in cryptic species

2021 ◽  
Author(s):  
Julia Serrano-Lobo ◽  
Ana Gómez ◽  
Belén Rodríguez-Sánchez ◽  
Patricia Muñoz ◽  
Pilar Escribano ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Cryptic Species ◽  
Screening Method ◽  
Fungal Growth ◽  
Poor Performance ◽  
Sensu Stricto ◽  
Azole Resistance ◽  
Major Error ◽  
Agar Method ◽  
The Impact

Azole-containing agar is used in routine Aspergillus fumigatus azole resistance screening. We evaluated the impact of the type of plastic used to prepare in-house agar plates on the procedurés performance against A. fumigatus sensu stricto and cryptic species. A. fumigatus sensu stricto (n=91) and cryptic species (n=52) were classified as susceptible or resistant (EUCAST E.Def 9.3.2; clinical breakpoints v10). In-house azole-containing agar plates were prepared following EUCAST E.Def 10.1 on three types of multi-dish plates. We assessed the sensitivity, specificity, and agreement values of the agar plates to screen for azole resistance. Overall, sensitivity and specificity values of the agar screening method were 100% and 93.3%, respectively. The type of tray used did not affect these values. All isolates harbouring TR 34 -L98H substitutions were classified as resistant to itraconazole and voriconazole by the agar method; however, false susceptibility (very major error) to posaconazole was not uncommon and happened in isolates with posaconazole MICs of 0.25 mg/L. Isolates harbouring G54R and TR 46 -Y121F-T289A substitutions were correctly classified by the agar method as itraconazole/posaconazole resistant and voriconazole-resistant, respectively. False resistance (major error) occurred in isolates showing tiny fungal growth. Finally, agreements between both procedures against cryptic species were much lower. Azole-containing agar plates are a convenient and reliable tool to screen for resistance in A. fumigatus sensu stricto ; the type of plastic tray used minimally affects the method. On the contrary, the performance against cryptic species is rather poor.

scholarly journals High prevalence of Itraconazole Resistance among Candida parapsilosis isolated from Iran

2019 ◽  
Author(s):  
Fozieh Hassanmoghadam ◽  
Tahereh Shokohi ◽  
Mohammad Taghi Hedayati ◽  
Narges Aslani ◽  
Iman Haghani ◽  
...  
Keyword(s):  
Candida Parapsilosis ◽  
Inhibitory Concentration ◽  
Antifungal Susceptibility ◽  
Reference Method ◽  
Sensu Stricto ◽  
Antifungal Drugs ◽  
High Prevalence ◽  
Invasive Infections ◽  
Prophylaxis Therapy

Background and Purpose: Candida parapsilosis isolates usually have a low minimum inhibitory concentration (MIC) against azoles. Although Candida parapsilosis isolates usually have low MICs against azoles, recent studies candida invasive infections due to azole resistant-C. parapsilosis isolates . Regarding this, the main aim of this study was to determine the susceptibility pattern of Iranian clinical C. parapsilosis against available azole antifungal drugs. Materials and Methods: This study was conducted on 105 previously-identified isolates of C. parapsilosis sensu stricto. For the purpose of the study, the isolates were subjected to antifungal susceptibility testing against fluconazole (FLZ), itraconazole (ITZ), voriconazole (VRZ), and two new azole drugs, namely luliconazole (LUZU) and lanoconazole (LZN). The broth microdilution reference method adopted in this study was according to the Clinical & Laboratory Standards Institute M27-A3 and M27-S4 documents. Results: According to the results, 89% (n=94) of C. parapsilosis isolates showed a MIC of ≥ 1 µg/ml, indicating resistance against ITZ. Multi-azole resistance was observed in 3.8% of the isolates. In addition, LUZU and LZN demonstrated the highest efficacy with the MIC50 values of 0.5 and 1 µg/ml, respectively. Conclusion: The majority of the isolates showed high MIC values against ITZ. This may have been associated with the long-term ITZ prophylaxis/therapy in patients infected with candidiasis. Hence, the adoption of an appropriate antifungal agent is a crucial step for starting the treatment.

scholarly journals Species Identification andIn VitroAntifungal Susceptibility ofAspergillus terreusSpecies Complex Clinical Isolates from a French Multicenter Study

2018 ◽  
Vol 62 (5) ◽  
pp. e02315-17 ◽  
Author(s):  
S. Imbert ◽  
A. C. Normand ◽  
S. Ranque ◽  
J. M. Costa ◽  
J. Guitard ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Antifungal Susceptibility ◽  
Sensu Stricto ◽  
Antifungal Drugs ◽  
Clinical Isolates ◽  
Clinical Samples ◽  
Azole Resistance ◽  
University Hospitals ◽  
Content Type ◽  
Interesting Alternative

ABSTRACTAspergillussectionTerreiis a species complex currently comprised of 14 cryptic species whose prevalence in clinical samples as well as antifungal susceptibility are poorly known. The aims of this study were to investigateA. Terreiclinical isolates at the species level and to perform antifungal susceptibility analyses by reference and commercial methods. Eighty-two clinicalA. Terreiisolates were collected from 8 French university hospitals. Molecular identification was performed by sequencing parts of beta-tubulin and calmodulin genes. MICs or minimum effective concentrations (MECs) were determined for 8 antifungal drugs using both EUCAST broth microdilution (BMD) methods and concentration gradient strips (CGS). Among the 79A. Terreiisolates,A. terreus stricto sensu(n= 61),A. citrinoterreus(n= 13),A. hortai(n= 3), andA. alabamensis(n= 2) were identified. All strains had MICs of ≥1 mg/liter for amphotericin B, except for two isolates (bothA. hortai) that had MICs of 0.25 mg/liter. FourA. terreusisolates were resistant to at least one azole drug, including one with pan-azole resistance, yet no mutation in theCYP51Agene was found. All strains had low MECs for the three echinocandins. The essential agreements (EAs) between BMD and CGS were >90%, except for those of amphotericin B (79.7%) and itraconazole (73.4%). Isolates belonging to theA. sectionTerreiidentified in clinical samples show wider species diversity beyond the knownA. terreus sensu stricto. Azole resistance inside the sectionTerreiis uncommon and is not related to CYP51A mutations here. Finally, CGS is an interesting alternative for routine antifungal susceptibility testing.

scholarly journals Environmental Isolates of Multi-Azole-Resistant Aspergillus spp. in Southern Italy

2018 ◽  
Vol 4 (4) ◽  
pp. 131 ◽  
Author(s):  
Laura Trovato ◽  
Guido Scalia ◽  
Maria Domina ◽  
Salvatore Oliveri
Keyword(s):  
Dna Sequencing ◽  
Southern Italy ◽  
Resistance Mechanism ◽  
Sensu Stricto ◽  
Surveillance Program ◽  
Azole Resistance ◽  
Environmental Isolates ◽  
Related Disease ◽  
First Time ◽  
Aspergillus Section

Azole resistance in Aspergillus spp. has been increasingly reported worldwide. Acquired azole resistance is probably linked to environmental exposure to fungicides used in agriculture. We collected a total of 84 soil and leaf samples from eight farms in Southern Italy. Aspergillus isolates were tested for resistance to itraconazole, posaconazole, and voriconazole by the EUCAST method. Five out of 84 samples yielded A. fumigatus isolates: four of them were itraconazole-resistant and were identified as A. fumigatus sensu stricto, three of them were posaconazole-resistant, and two were also voriconazole-resistant. All three isolates harbored the TR34/L98H resistance mechanism, which was detected by DNA sequencing of the cyp51A gene. Fifteen out of 84 samples yielded Aspergillus spp. isolates and included 11 itraconazole-resistant isolates: Aspergillus section Nigri (9) and Aspergillus section Flavi (2). Our study reports for the first time the isolation of azole-resistant A. fumigatus harboring TR34/L98H mutation from the environment of Southern Italy. The present work provides a better understanding of the magnitude of the environmental spread of azole resistance in the context of a necessary effective surveillance program to improve the management of Aspergillus-related disease.

scholarly journals Recent Exposure to Caspofungin or Fluconazole Influences the Epidemiology of Candidemia: a Prospective Multicenter Study Involving 2,441 Patients

2010 ◽  
Vol 55 (2) ◽  
pp. 532-538 ◽  
Author(s):  
Olivier Lortholary ◽  
Marie Desnos-Ollivier ◽  
Karine Sitbon ◽  
Arnaud Fontanet ◽  
Stéphane Bretagne ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Odds Ratio ◽  
Susceptibility Testing ◽  
Antifungal Susceptibility ◽  
Bloodstream Infections ◽  
Antifungal Drugs ◽  
Surveillance Program ◽  
Prospective Multicenter Study ◽  
Recent Exposure ◽  
Adults And Children

ABSTRACTA prospective multicenter surveillance program on yeast bloodstream infections was implemented in the Paris, France, area without restrictions on ward of hospitalization (intensive care unit, hematology, and surgery) or age (adults and children). The present analysis concerns 2,618 isolates collected over 7 years from 2,441 patients. Centralized species identification and antifungal susceptibility testing using the EUCAST methodology were performed. Almost 10% (232/2,441) of the patients had recently (≤30 days) been treated with antifungal drugs. We analyzed the effect of recent exposure to fluconazole (n= 159) or caspofungin (n= 61) on the proportions of the five majorCandidaspecies. For both drugs, preexposure was associated with a decreased prevalence ofCandida albicansin favor of less drug-susceptible species (C. glabrataandC. kruseifor the former andC. parapsilosisand, to a lesser extent,C. glabrataandC. kruseifor the latter;P= 0.001). In the multivariate analysis, the risk of being infected with an isolate with decreased susceptibility to fluconazole was independently associated with an age of ≥15 years (odds ratio [OR] = 2.45; 95% confidence interval [CI] = 1.39 to 4.31;P= 0.002) and with recent exposure to fluconazole (OR = 2.17; 95% CI = 1.51 to 3.13;P< 0.001), while the risk of being infected with an isolate with decreased susceptibility to caspofungin was independently associated with an age <15 years (OR = 2.53; 95% CI = 1.43 to 4.48;P= 0.001) and with recent exposure to caspofungin (OR = 4.79; 95% CI = 2.47 to 9.28;P< 0.001). These findings could influence future recommendations for the management of candidemia.

scholarly journals Differential response to heat stress among evolutionary lineages of an aquatic invertebrate species complex

2018 ◽  
Vol 14 (11) ◽  
pp. 20180498 ◽  
Author(s):  
Sofia Paraskevopoulou ◽  
Ralph Tiedemann ◽  
Guntram Weithoff
Keyword(s):  
Heat Stress ◽  
Cryptic Species ◽  
Heat Tolerance ◽  
Species Complex ◽  
Environmental Changes ◽  
Integrative Taxonomy ◽  
Sensu Stricto ◽  
Apparent Temperature ◽  
Phenotypic Trait ◽  
Evolutionary Lineages

Under global warming scenarios, rising temperatures can constitute heat stress to which species may respond differentially. Within a described species, knowledge on cryptic diversity is of further relevance, as different lineages/cryptic species may respond differentially to environmental change. The Brachionus calyciflorus species complex (Rotifera), which was recently described using integrative taxonomy, is an essential component of aquatic ecosystems. Here, we tested the hypothesis that these (formerly cryptic) species differ in their heat tolerance. We assigned 47 clones with nuclear ITS1 (nuITS1) and mitochondrial COI (mtCOI) markers to evolutionary lineages, now named B. calyciflorus sensu stricto (s.s.) and B. fernandoi . We selected 15 representative clones and assessed their heat tolerance as a bi-dimensional phenotypic trait affected by both the intensity and duration of heat stress. We found two distinct groups, with B. calyciflorus s.s. clones having higher heat tolerance than the novel species B. fernandoi . This apparent temperature specialization among former cryptic species underscores the necessity of a sound species delimitation and assignment, when organismal responses to environmental changes are investigated.

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