scholarly journals Epidemiology and Antifungal Susceptibility Profile of Aspergillus Species: Comparison between Environmental and Clinical Isolates from Patients with Hematologic Malignancies

2019 ◽  
Vol 57 (7) ◽  
Author(s):  
Sung-Yeon Cho ◽  
Dong-Gun Lee ◽  
Won-Bok Kim ◽  
Hye-Sun Chun ◽  
Chulmin Park ◽  
...  
Keyword(s):  
Invasive Aspergillosis ◽  
Cryptic Species ◽  
Hematologic Malignancy ◽  
Antifungal Susceptibility ◽  
Hematologic Malignancies ◽  
Clinical Isolates ◽  
Environmental Isolates ◽  
Content Type ◽  
Culture Positive ◽  
Global Data

ABSTRACT Global data on the epidemiology and susceptibility of Aspergillus are crucial in the management of invasive aspergillosis. Here, we aimed to determine the characteristics of clinical and environmental Aspergillus isolates, focusing mainly on hematologic malignancy patients. We prospectively collected all consecutive cases and clinical isolates of culture-positive proven/probable invasive aspergillosis patients from January 2016 to April 2018 and sampled the air inside and outside the hospital. Cryptic species-level identification of Aspergillus, antifungal susceptibilities, and cyp51 gene sequencing were performed, and clinical data were analyzed. This study was conducted as part of the Catholic Hematology Hospital Fungi Epidemiology (CAFÉ) study. A total of 207 proven/probable invasive aspergillosis and 102 clinical and 129 environmental Aspergillus isolates were included in this analysis. The incidence of proven/probable invasive aspergillosis was 1.3 cases/1,000 patient-days during the study period. Cryptic Aspergillus species accounted for 33.8%, with no differences in proportions between the clinical and environmental isolates. Section Nigri presented a high proportion (70.5%) of cryptic species, mainly from A. tubingensis and A. awamori: the former being dominant in environmental samples, and the latter being more common in clinical isolates (P < 0.001). Of 91 A. fumigatus isolates, azole-resistant A. fumigatus was found in 5.3% of all A. fumigatus isolates. Three isolates presented the TR34/L98H mutation of the cyp51A gene. Patients with invasive aspergillosis caused by azole-resistant A. fumigatus showed 100% all-cause mortality at 100 days. This study demonstrates the significant portion of cryptic Aspergillus species and clinical implications of azole resistance and underscores the comparison between clinical and environmental isolates.

scholarly journals Is Azole Resistance in Aspergillus fumigatus a Problem in Spain?

2013 ◽  
Vol 57 (6) ◽  
pp. 2815-2820 ◽  
Author(s):  
Pilar Escribano ◽  
Teresa Peláez ◽  
Patricia Muñoz ◽  
Emilio Bouza ◽  
Jesús Guinea
Keyword(s):  
Invasive Aspergillosis ◽  
Aspergillus Fumigatus ◽  
Cryptic Species ◽  
Antifungal Susceptibility ◽  
Single Species ◽  
Azole Resistance ◽  
Tubulin Gene ◽  
Complex Species ◽  
Content Type ◽  
Β Tubulin

ABSTRACTAspergillus fumigatuscomplex comprisesA. fumigatusand other morphologically indistinguishable cryptic species. We retrospectively studied 362A. fumigatuscomplex isolates (353 samples) from 150 patients with proven or probable invasive aspergillosis or aspergilloma (2, 121, and 6 samples, respectively) admitted to the hospital from 1999 to 2011. Isolates were identified using the β-tubulin gene, and only 1 isolate per species found in each sample was selected. Antifungal susceptibility to azoles was determined using the CLSI M38-A2 procedure. Isolates were considered resistant if they showed an MIC above the breakpoints for itraconazole, voriconazole, or posaconazole (>2, >2, or >0.5 μg/ml). Most of the samples yielded only 1 species (A. fumigatus[n= 335],A. novofumigatus[n= 4],A. lentulus[n= 3],A. viridinutans[n= 1], andNeosartorya udagawae[n= 1]). The remaining samples yielded a combination of 2 species. Most of the patients were infected by a single species (A. fumigatus[n= 143] orA. lentulus[n= 2]). The remaining 5 patients were coinfected with multipleA. fumigatuscomplex species, althoughA. fumigatuswas always involved; 4 of the 5 patients were diagnosed in 2009 or later. Cryptic species were less susceptible thanA. fumigatus. The frequency of resistance amongA. fumigatuscomplex andA. fumigatusto itraconazole, voriconazole, and posaconazole was 2.5 and 0.3%, 3.1 and 0.3%, and 4.2 and 1.8%, respectively, in the per-isolate analysis and 1.3 and 0.7%, 2.6 and 0.7%, and 6 and 4% in the per-patient analysis. Only 1 of the 6A. fumigatusisolates in which thecyp51Agene was sequenced had a mutation at position G448. The proportion of patients infected by azole-resistantA. fumigatusisolates was low.

scholarly journals Molecular Identification, Antifungal Susceptibility Profile, and Biofilm Formation of Clinical and Environmental Rhodotorula Species Isolates

2012 ◽  
Vol 57 (1) ◽  
pp. 382-389 ◽  
Author(s):  
Jorge Meneses Nunes ◽  
Fernando César Bizerra ◽  
Renata Carmona e Ferreira ◽  
Arnaldo Lopes Colombo
Keyword(s):  
Amphotericin B ◽  
Biofilm Formation ◽  
Fungal Pathogens ◽  
Antifungal Susceptibility ◽  
Nitrate Assimilation ◽  
Clinical Isolates ◽  
Its Sequencing ◽  
Environmental Isolates ◽  
Content Type

ABSTRACTRhodotorulaspecies are emergent fungal pathogens capable of causing invasive infections, primarily fungemia. They are particularly problematic in immunosuppressed patients when using a central venous catheter. In this study, we evaluated the species distribution of 51 clinical and 8 environmentalRhodotorulaspecies isolates using the ID32C system and internal transcribed spacer (ITS) sequencing. Antifungal susceptibility testing and biofilm formation capability using a crystal violet staining assay were performed. Using ITS sequencing as the gold standard, the clinical isolates were identified as follows: 44R. mucilaginosaisolates, 2R. glutinisisolates, 2R. minutaisolates, 2R. dairenensisisolates, and 1Rhodosporidium fluvialeisolate. The environmental isolates included 7R. mucilaginosaisolates and 1R. slooffiaeisolate. Using the ID32C system, along with a nitrate assimilation test, only 90.3% of the isolates tested were correctly identified. In the biofilm formation assay,R. mucilaginosaandR. minutaexhibited greater biofilm formation ability compared to the otherRhodotorulaspecies; the clinical isolates ofR. mucilaginosashowed greater biofilm formation compared to the environmental isolates (P= 0.04). Amphotericin B showed goodin vitroactivity (MIC ≤ 1 μg/ml) against planktonic cells, whereas voriconazole and posaconazole showed poor activity (MIC50/MIC90, 2/4 μg/ml). Caspofungin and fluconazole MICs were consistently high for all isolates tested (≥64 μg/ml and ≥ 4 μg/ml, respectively). In this study, we emphasized the importance of molecular methods to correctly identifyRhodotorulaspecies isolates and non-R. mucilaginosaspecies in particular. The antifungal susceptibility profile reinforces amphotericin B as the antifungal drug of choice for the treatment ofRhodotorulainfections. To our knowledge, this is the first study evaluating putative differences in the ability of biofilm formation among differentRhodotorulaspecies.

scholarly journals Cryptic Species and Azole Resistance in the Aspergillus niger Complex

2011 ◽  
Vol 55 (10) ◽  
pp. 4802-4809 ◽  
Author(s):  
Susan J. Howard ◽  
Elizabeth Harrison ◽  
Paul Bowyer ◽  
Janos Varga ◽  
David W. Denning
Keyword(s):  
Aspergillus Niger ◽  
Cryptic Species ◽  
Phylogenetic Trees ◽  
Antifungal Susceptibility ◽  
Clinical Isolates ◽  
Cross Resistance ◽  
Azole Resistance ◽  
Beta Tubulin ◽  
Data Set ◽  
Content Type

ABSTRACTAspergillus nigeris a common clinical isolate. Multiple species comprise theAspergillussectionNigriand are separable using sequence data. The antifungal susceptibility of these cryptic species is not known. We determined the azole MICs of 50 black aspergilli, 45 from clinical specimens, using modified EUCAST (mEUCAST) and Etest methods. Phylogenetic trees were prepared using the internal transcribed spacer, beta-tubulin, and calmodulin sequences to identify strains to species level and the results were compared with those obtained withcyp51Asequences. We attempted to correlatecyp51Amutations with azole resistance. Etest MICs were significantly different from mEUCAST MICs (P< 0.001), with geometric means of 0.77 and 2.79 mg/liter, respectively. Twenty-six of 50 (52%) isolates were itraconazole resistant by mEUCAST (MICs > 8 mg/liter), with limited cross-resistance to other azoles. Using combined beta-tubulin/calmodulin sequences, the 45 clinical isolates grouped into 5 clades,A. awamori(55.6%),A. tubingensis(17.8%),A. niger(13.3%),A. acidus(6.7%), and an unknown group (6.7%), none of which were morphologically distinguishable. Itraconazole resistance was found in 36% of the isolates in theA. awamorigroup, 90% of theA. tubingensisgroup, 33% of theA. nigergroup, 100% of theA. acidusgroup, and 67% of the unknown group. These data suggest thatcyp51Amutations in sectionNigrimay not play as important a role in azole resistance as inA. fumigatus, although some mutations (G427S, K97T) warrant further study. Numerous cryptic species are found in clinical isolates of theAspergillussectionNigriand are best reported as “A. nigercomplex” by clinical laboratories. Itraconazole resistance was common in this data set, but azole cross-resistance was unusual. The mechanism of resistance remains obscure.

scholarly journals Aspergillus fumigatus Clinical Isolates Carrying CYP51A with TR34/L98H/S297T/F495I Substitutions Detected after Four-Year Retrospective Azole Resistance Screening in Brazil

2019 ◽  
Vol 64 (3) ◽  
Author(s):  
Laís Pontes ◽  
Caio Augusto Gualtieri Beraquet ◽  
Teppei Arai ◽  
Guilherme Leite Pigolli ◽  
Luzia Lyra ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Tandem Repeat ◽  
Antifungal Susceptibility ◽  
Antifungal Resistance ◽  
Clinical Isolates ◽  
Azole Resistance ◽  
Resistance Screening ◽  
Environmental Isolates ◽  
Content Type ◽  
Susceptibility Tests

ABSTRACT Azole antifungal resistance in Aspergillus fumigatus is a worldwide concern. As in most public hospitals in Brazil, antifungal susceptibility tests are not routinely performed for filamentous fungi at our institution. A 4-year retrospective azole antifungal resistance screening revealed two azole-resistant A. fumigatus clinical isolates carrying the CYP51A TR34 (34-bp tandem repeat)/L98H (change of L to H at position 98)/S297T/F495I resistance mechanism mutations, obtained from two unrelated patients. Broth microdilution antifungal susceptibility testing showed high MICs for itraconazole, posaconazole, and miconazole. Short tandem repeat (STR) typing analysis presented high levels of similarity between these two isolates and clinical isolates with the same mutations reported from the Netherlands, Denmark, and China, as well as environmental isolates from Taiwan. Our findings might indicate that active searching for resistant A. fumigatus is necessary. They also represent a concern considering that our hospital provides tertiary care assistance to immunocompromised patients who may be exposed to resistant environmental isolates. We also serve patients who receive prophylactic antifungal therapy or treatment for invasive fungal infections for years. In these two situations, isolates resistant to the antifungal in use may be selected within the patients themselves. We do not know the potential of this azole-resistant A. fumigatus strain to spread throughout our country. In this scenario, the impact on the epidemiology and use of antifungal drugs will significantly alter patient care, as in other parts of the world. In summary, this finding is an important contribution to alert hospital laboratories conducting routine microbiological testing to perform azole resistance surveillance and antifungal susceptibility tests of A. fumigatus isolates causing infection or colonization in patients at high risk for systemic aspergillosis.

scholarly journals Host Carbon Dioxide Concentration Is an Independent Stress for Cryptococcus neoformans That Affects Virulence and Antifungal Susceptibility

mBio ◽  
2019 ◽  
Vol 10 (4) ◽  
Author(s):  
Damian J. Krysan ◽  
Bing Zhai ◽  
Sarah R. Beattie ◽  
Kara M. Misel ◽  
Melanie Wellington ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Cryptococcus Neoformans ◽  
Carbon Dioxide Concentration ◽  
Antifungal Drugs ◽  
Clinical Isolates ◽  
Mammalian Host ◽  
Environmental Isolates ◽  
Capsule Formation ◽  
Content Type ◽  
Virulence Traits

ABSTRACT The ability of Cryptococcus neoformans to cause disease in humans varies significantly among strains with highly related genotypes. In general, environmental isolates of pathogenic species such as Cryptococcus neoformans var. grubii have reduced virulence relative to clinical isolates, despite having no differences in the expression of the canonical virulence traits (high-temperature growth, melanization, and capsule formation). In this observation, we report that environmental isolates of C. neoformans tolerate host CO2 concentrations poorly compared to clinical isolates and that CO2 tolerance correlates well with the ability of the isolates to cause disease in mammals. Initial experiments also suggest that CO2 tolerance is particularly important for dissemination of C. neoformans from the lung to the brain. Furthermore, CO2 concentrations affect the susceptibility of both clinical and environmental C. neoformans isolates to the azole class of antifungal drugs, suggesting that antifungal testing in the presence of CO2 may improve the correlation between in vitro azole activity and patient outcome. IMPORTANCE A number of studies comparing either patient outcomes or model system virulence across large collections of Cryptococcus isolates have found significant heterogeneity in virulence even among strains with highly related genotypes. Because this heterogeneity cannot be explained by variations in the three well-characterized virulence traits (growth at host body temperature, melanization, and polysaccharide capsule formation), it has been widely proposed that additional C. neoformans virulence traits must exist. The natural niche of C. neoformans is in the environment, where the carbon dioxide concentration is very low (∼0.04%); in contrast, mammalian host tissue carbon dioxide concentrations are 125-fold higher (5%). We have found that the ability to grow in the presence of 5% carbon dioxide distinguishes low-virulence strains from high-virulence strains, even those with a similar genotype. Our findings suggest that carbon dioxide tolerance is a previously unrecognized virulence trait for C. neoformans.

scholarly journals Polyphasic Identification and Susceptibility to Seven Antifungals of 102 Aspergillus Isolates Recovered from Immunocompromised Hosts in Greece

2011 ◽  
Vol 55 (6) ◽  
pp. 3025-3030 ◽  
Author(s):  
Michael Arabatzis ◽  
Manousos Kambouris ◽  
Miltiades Kyprianou ◽  
Aikaterini Chrysaki ◽  
Maria Foustoukou ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Antifungal Susceptibility ◽  
Clinical Isolates ◽  
Content Type ◽  
Susceptibility Study ◽  
Immunocompromised Hosts

ABSTRACTIn this study, the first such study in Greece, we used polyphasic identification combined with antifungal susceptibility study to analyzeAspergillusclinical isolates comprising 102 common and rare members of sections Fumigati, Flavi, Terrei, Nidulantes, Nigri, Circumdati, Versicolores, and Usti. High amphotericin B MICs (>2 μg/ml) were found for 17.6% of strains. Itraconazole, posaconazole, and voriconazole MICs of >4 μg/ml were shown in 1%, 5%, and 0% of the isolates, respectively. Anidulafungin, micafungin, and caspofungin minimum effective concentrations (MECs) of ≥2 μg/ml were correspondingly recorded for 4%, 9%, and 33%, respectively, of the strains.

scholarly journals Genetic Diversity of Clinical and Environmental Vibrio parahaemolyticus Strains from the Pacific Northwest

2012 ◽  
Vol 78 (24) ◽  
pp. 8631-8638 ◽  
Author(s):  
Rohinee Paranjpye ◽  
Owen S. Hamel ◽  
Asta Stojanovski ◽  
Martin Liermann
Keyword(s):  
Pacific Northwest ◽  
Vibrio Parahaemolyticus ◽  
The United States ◽  
Assessment Tools ◽  
Clinical Isolates ◽  
Environmental Isolates ◽  
Content Type ◽  
The Pacific ◽  
Geographical Regions ◽  
Thermostable Direct Hemolysin

ABSTRACTSince 1997, cases ofVibrio parahaemolyticus-related gastroenteritis from the consumption of raw oysters harvested in Washington State have been higher than historical levels. These cases have shown little or no correlation with concentrations of potentially pathogenicV. parahaemolyticus(positive for the thermostable direct hemolysin gene,tdh) in oysters, although significant concentrations oftdh+V. parahaemolyticusstrains were isolated from shellfish-growing areas in the Pacific Northwest (PNW). We compared clinical and environmental strains isolated from the PNW to those from other geographic regions within the United States and Asia for the presence of virulence-associated genes, including the thermostable direct hemolysin (tdh), the thermostable-related hemolysin (trh), urease (ureR), the pandemic group specific markersorf8andtoxRS, and genes encoding both type 3 secretion systems (T3SS1 and T3SS2). The majority of clinical strains from the PNW were positive fortdh,trh, andureRgenes, while a significant proportion of environmental isolates weretdh+buttrhnegative. Hierarchical clustering grouped the majority of these clinical isolates into a cluster distinct from that including the pandemic strain RIMD2210633, clinical isolates from other geographical regions, andtdh+,trh-negative environmental isolates from the PNW. We detected T3SS2-related genes (T3SS2β) in environmental strains that weretdhandtrhnegative. The presence of significant concentrations oftdh+,trh-negative environmental strains in the PNW that have not been responsible for illness and T3SS2β intdh- andtrh-negative strains emphasizes the diversity in this species and the need to identify additional virulence markers for this bacterium to improve risk assessment tools for the detection of this pathogen.

scholarly journals Legionella pneumophilaand OtherLegionellaSpecies Isolated from Legionellosis Patients in Japan between 2008 and 2016

2018 ◽  
Vol 84 (18) ◽  
Author(s):  
Junko Amemura-Maekawa ◽  
Fumiaki Kura ◽  
Kyoko Chida ◽  
Hitomi Ohya ◽  
Jun-ichi Kanatani ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Minimum Spanning Tree ◽  
Clinical Isolates ◽  
Small Scale ◽  
Environmental Isolates ◽  
Content Type ◽  
Suspected Infection ◽  
Source Of Infection ◽  
Infection Source ◽  
Bath Water

ABSTRACTTheLegionellaReference Center in Japan collected 427Legionellaclinical isolates between 2008 and 2016, including 7 representative isolates from corresponding outbreaks. The collection included 419Legionella pneumophilaisolates, of which 372 belonged to serogroup 1 (SG1) (87%) and the others belonged to SG2 to SG15 except for SG7 and SG11, and 8 isolates of otherLegionellaspecies (Legionella bozemanae,Legionella dumoffii,Legionella feeleii,Legionella longbeachae,Legionella londiniensis, andLegionella rubrilucens).L. pneumophilaisolates were genotyped by sequence-based typing (SBT) and represented 187 sequence types (STs), of which 126 occurred in a single isolate (index of discrimination of 0.984). These STs were analyzed using minimum spanning tree analysis, resulting in the formation of 18 groups. The pattern of overall ST distribution amongL. pneumophilaisolates was diverse. In particular, some STs were frequently isolated and were suggested to be related to the infection sources. The major STs were ST23 (35 isolates), ST120 (20 isolates), and ST138 (16 isolates). ST23 was the most prevalent and most causative ST for outbreaks in Japan and Europe. ST138 has been observed only in Japan, where it has caused small-scale outbreaks; 81% of those strains (13 isolates) were suspected or confirmed to infect humans through bath water sources. On the other hand, 11 ST23 strains (31%) and 5 ST120 strains (25%) were suspected or confirmed to infect humans through bath water. These findings suggest that some ST strains frequently cause legionellosis in Japan and are found under different environmental conditions.IMPORTANCELegionella pneumophilaserogroup 1 (SG1) is the most frequent cause of legionellosis. Our previous genetic analysis indicated that SG1 environmental isolates represented 8 major clonal complexes, consisting of 3 B groups, 2 C groups, and 3 S groups, which included major environmental isolates derived from bath water, cooling towers, and soil and puddles, respectively. Here, we surveyed clinical isolates collected from patients with legionellosis in Japan between 2008 and 2016. Most strains belonging to the B group were isolated from patients for whom bath water was the suspected or confirmed source of infection. Among the isolates derived from patients whose suspected infection source was soil or dust, most belonged to the S1 group and none belonged to the B or C groups. Additionally, the U group was discovered as a new group, which mainly included clinical isolates with unknown infection sources.

scholarly journals Multicentric Analysis of the Species Distribution and Antifungal Susceptibility of Cryptic Isolates from Aspergillus Section Fumigati

2020 ◽  
Vol 64 (12) ◽  
Author(s):  
S. Imbert ◽  
A. C. Normand ◽  
S. Cassaing ◽  
F. Gabriel ◽  
L. Kristensen ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Amphotericin B ◽  
Species Distribution ◽  
Concentration Gradient ◽  
Antifungal Susceptibility ◽  
Reference Method ◽  
Content Type ◽  
Species Specific ◽  
High Mics ◽  
Aspergillus Section

ABSTRACT The antifungal susceptibility of Aspergillus cryptic species is poorly known. We assessed 51 isolates, belonging to seven Fumigati cryptic species, by the EUCAST reference method and the concentration gradient strip (CGS) method. Species-specific patterns were observed, with high MICs for azole drugs, except for Aspergillus hiratsukae and Aspergillus tsurutae, and high MICs for amphotericin B for Aspergillus lentulus and Aspergillus udagawae. Essential and categorical agreements between EUCAST and CGS results were between 53.3 and 93.3%.

scholarly journals Species Distribution and Comparison between EUCAST and Gradient Concentration Strips Methods for Antifungal Susceptibility Testing of 112 Aspergillus Section Nigri Isolates

2020 ◽  
Vol 64 (7) ◽  
Author(s):  
B. Carrara ◽  
R. Richards ◽  
S. Imbert ◽  
F. Morio ◽  
M. Sasso ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Amphotericin B ◽  
Species Distribution ◽  
Antifungal Susceptibility ◽  
Rank Correlation ◽  
Common Species ◽  
Teaching Hospitals ◽  
Nucleotide Sequence Analysis ◽  
Accurate Identification ◽  
Content Type

ABSTRACT Aspergillus niger, the third species responsible for invasive aspergillosis, has been considered as a homogeneous species until DNA-based identification uncovered many cryptic species. These species have been recently reclassified into the Aspergillus section Nigri. However, little is yet known among the section Nigri about the species distribution and the antifungal susceptibility pattern of each cryptic species. A total of 112 clinical isolates collected from 5 teaching hospitals in France and phenotypically identified as A. niger were analyzed. Identification to the species level was carried out by nucleotide sequence analysis. The MICs of itraconazole, voriconazole, posaconazole, isavuconazole, and amphotericin B were determined by both the EUCAST and gradient concentration strip methods. Aspergillus tubingensis (n = 51, 45.5%) and Aspergillus welwitschiae (n = 50, 44.6%) were the most common species while A. niger accounted for only 6.3% (n = 7). The MICs of azole drugs were higher for A. tubingensis than for A. welwitschiae. The MIC of amphotericin B was 2 mg/liter or less for all isolates. Importantly, MICs determined by EUCAST showed no correlation with those determined by the gradient concentration strip method, with the latter being lower than the former (Spearman’s rank correlation tests ranging from 0.01 to 0.25 depending on the antifungal agent; P > 0.4). In conclusion, A. niger should be considered as a minority species in the section Nigri. The differences in MICs between species for different azoles underline the importance of accurate identification. Significant divergences in the determination of MIC between EUCAST and the gradient concentration strip methods require further investigation.

Sign in / Sign up

Export Citation Format

Share Document