Evidence map›Paper›PMID 21768508›Full record

ArticleAntimicrobial agents and chemotherapy2011

Cryptic species and azole resistance in the Aspergillus niger complex.

Susan J Howard, Elizabeth Harrison, Paul Bowyer, Janos Varga, David W Denning

Open access · bronzeAbstract read
In one paragraph

Article in Antimicrobial agents and chemotherapy, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 60 papers.

0numbers the graph read from it
0cells of the map it votes in
60citing papers in PubMed
3.8field-weighted citation impact, top 6% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

60 citing papers in PubMed, 130 citations in OpenAlex.

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  16. Diagnosis and Treatment of Invasive Aspergillosis Caused by Non-Journal of fungi (Basel, Switzerland) · 2023
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 2 institutions in 1 country.

Susan J HowardThe University of Manchester, 1.800 Stopford Building, Oxford Road, Manchester M13 9PT, United Kingdom. susan.j.howard@manchester.ac.uk
Elizabeth Harrison
Paul Bowyer
Janos Varga
David W Denning
University of Manchester · GBManchester Academic Health Science Centre · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Aspergillus niger is a common clinical isolate. Multiple species comprise the Aspergillus section Nigri and 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 with cyp51A sequences. We attempted to correlate cyp51A mutations 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 the A. awamori group, 90% of the A. tubingensis group, 33% of the A. niger group, 100% of the A. acidus group, and 67% of the unknown group. These data suggest that cyp51A mutations in section Nigri may not play as important a role in azole resistance as in A. fumigatus, although some mutations (G427S, K97T) warrant further study. Numerous cryptic species are found in clinical isolates of the Aspergillus section Nigri and are best reported as "A. niger complex" by clinical laboratories. Itraconazole resistance was common in this data set, but azole cross-resistance was unusual. The mechanism of resistance remains obscure.

Indexed as

Antifungal AgentsAspergillosisAspergillus nigerAzolesBase SequenceCalmodulinCytochrome P-450 Enzyme SystemDNA, IntergenicDrug Resistance, FungalFungal ProteinsItraconazoleMicrobial Sensitivity TestsMutationPhylogenySequence AlignmentSequence Analysis, DNAAntifungal AgentsAzolesCalmodulincytochrome P-450 CYP51A, AspergillusCytochrome P-450 Enzyme SystemDNA, IntergenicFungal ProteinsItraconazoleTubulin

Identifiers

PMID21768508
PMCPMC3186969
OpenAlexW2132684519

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.