Evaluating VITEK MS for the identification of clinically relevant Aspergillus species

2019 ◽  
Vol 58 (3) ◽  
pp. 322-327 ◽  
Author(s):  
Fernanda M Américo ◽  
Lumena P Machado Siqueira ◽  
Gilda Maria B Del Negro ◽  
Viviane M Favero Gimenes ◽  
Mario Roberto S Trindade ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Species Identification ◽  
Fungal Infections ◽  
Species Level ◽  
Aspergillus Species ◽  
Accurate Identification ◽  
Spectral Profiles ◽  
Correct Species Identification ◽  
Vitek Ms ◽  
Section Level

Abstract Aspergillus spp. identification has become more relevant in clinical practice since azole-resistant cryptic species have been related to invasive fungal infections. Conventional morphologic identification is not able to discriminate Aspergillus species, and DNA sequencing is not feasible for clinical laboratories. MALDI-TOF mass spectrometry is an emergent technology that has been explored to provide fast and accurate identification of microorganisms, including clinically relevant moulds. However, only a few studies have explored the platform VITEK MS for the identification of Aspergillus species. Hence, we provided additional data regarding the performance of the VITEK MS system for the identification of Aspergillus species, including azole-resistant ones. We also improved the RUO system by adding additional spectral profiles from well-identified Aspergillus strains belonging to different noncryptic and cryptic species. The IVD library correctly identified 91.6% of the organisms at genus and section level, and 84.7% at species level, including the azole-resistant Aspergillus lentulus and Aspergillus calidoustus. The organisms belonging to Aspergillus cryptic species had only 31.2% of correct species identification. The RUO library plus our in-house SuperSpectra correctly identified 100% of the organisms at genus and section level and 91.6% at species level. Among organisms belonging to Aspergillus cryptic species, 68.7% had correct species identification. Some closely related Aspergillus cryptic species showed similar spectral profiles and were difficult to be differentiated.

Multi-centric evaluation of the online MSI platform for the identification of cryptic and rare species of Aspergillus by MALDI-TOF

2019 ◽  
Vol 57 (8) ◽  
pp. 962-968 ◽  
Author(s):  
Sébastien Imbert ◽  
Anne Cécile Normand ◽  
Frédéric Gabriel ◽  
Sophie Cassaing ◽  
Christine Bonnal ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cryptic Species ◽  
Rare Species ◽  
Sensu Stricto ◽  
Species Level ◽  
Identification Accuracy ◽  
Mass Spectrometry Identification ◽  
Almost All ◽  
Level Identification ◽  
Section Level

Abstract The taxonomy of Aspergillus species has recently been revolutionized with the introduction of cryptic species and section concepts. However, their species-level identification in routine laboratories remains a challenge. The aim of this study was to prospectively assess the identification accuracy of cryptic species of Aspergillus in various laboratories using the mass spectrometry identification (MSI) platform, an independent and freely accessible online mass spectrometry database. Over a 12-month period, when a select set of MSI users identified cryptic species, they were contacted and requested to send the isolates to our laboratory for sequence-based identification. Sequence and MSI identification results were then compared. During the study period, 5108 Aspergillus isolates were identified using MSI including 1477 (28.9%) cryptic species. A total of 245 isolates that corresponded to 56 cryptic species and 13 sections were randomly selected for DNA sequencing confirmation. Agreement between the two methods was 99.6% at the section level and 66.1% at the species level. However, almost all discrepancies (72/83, 86.7%) were misidentifications between closely related cryptic species belonging to the same section. Fifty-one isolates from noncryptic species were also identified, thus yielding 100% and 92.2% agreement at the section and species level, respectively. Although the MSI fungus database is a reliable tool to identify Aspergillus at the section level, the database still requires adjustment to correctly identify rare or cryptic species at the species level. Nevertheless, the application properly differentiated between cryptic and sensu stricto species in the same section, thus alerting on possible specific isolate characteristics.

scholarly journals Multicenter Evaluation of the Vitek MS v3.0 System for the Identification of Filamentous Fungi

2017 ◽  
Vol 56 (2) ◽  
Author(s):  
Jenna Rychert ◽  
E. Sue Slechta ◽  
Adam P. Barker ◽  
Edwin Miranda ◽  
N. Esther Babady ◽  
...  
Keyword(s):  
Fungal Infections ◽  
Species Level ◽  
Correct Identification ◽  
Ionization Time ◽  
Fungal Identification ◽  
Morphological Criteria ◽  
Clinical Mycology ◽  
Speed Up ◽  
Appropriate Therapy ◽  
Vitek Ms

ABSTRACT Invasive fungal infections are an important cause of morbidity and mortality affecting primarily immunocompromised patients. While fungal identification to the species level is critical to providing appropriate therapy, it can be slow and laborious and often relies on subjective morphological criteria. The use of matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry has the potential to speed up and improve the accuracy of identification. In this multicenter study, we evaluated the accuracy of the Vitek MS v3.0 system in identifying 1,601 clinical mold isolates compared to identification by DNA sequence analysis and supported by morphological and phenotypic testing. Among the 1,519 isolates representing organisms in the v3.0 database, 91% (n = 1,387) were correctly identified to the species level. An additional 27 isolates (2%) were correctly identified to the genus level. Fifteen isolates were incorrectly identified, due to either a single incorrect identification (n = 13) or multiple identifications from different genera (n = 2). In those cases, when a single identification was provided that was not correct, the misidentification was within the same genus. The Vitek MS v3.0 was unable to identify 91 (6%) isolates, despite repeat testing. These isolates were distributed among all the genera. When considering all isolates tested, even those that were not represented in the database, the Vitek MS v3.0 provided a single correct identification 98% of the time. These findings demonstrate that the Vitek MS v3.0 system is highly accurate for the identification of common molds encountered in the clinical mycology laboratory.

scholarly journals Psychrobacter immobilis isolated from foods: characteristics and identification

2015 ◽  
Vol 46 (No. 4) ◽  
pp. 95-100 ◽  
Author(s):  
Z. Páčová ◽  
E. Urbanová ◽  
E. Durnová
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Species Identification ◽  
Species Level ◽  
The Other ◽  
Identification System ◽  
Conventional Tests ◽  
Comamonas Terrigena ◽  
Correct Species Identification

A total of 15 strains of Psychrobacter immobilis isolated from animal sources, e.g. cheese, fish and poultry, were tested. A commercial diagnostic kit NEFERMtest 24, conventional tests and determination of fatty acids were used for identification. By using the results of NEFERMtest 24 and numerical identification system TNW version 6.0 the identification was successful on the species level (46.7%) while the correct species identification by using conventional tests increased up to 86.7%. All 9 saccharolytic strains including 7 Czech isolates were identified in most cases on an excellent or very good level by both methods based on biochemical reactions. On the other hand, the identification of 6 asaccharolytic strains was unsuccessful especially by NEFERMtest 24. While 4 asaccharolytic strains were identified correctly on the basis of conventional tests on species or genus level, incorrect identification on species level, for example Ralstonia paucula, Comamonas terrigena, Oligella ureolytica, Moraxella lincolnii andPsychrobacter phenylpyruvicus, was found by using NEFERMtest 24. Determination of fatty acid composition by MIDI System confirmed the species identification of 9 out of the 10 tested strains of P. immobilis and 1 tested strain of Psychrobacter sp.

scholarly journals Performance of Five Commercial Identification Platforms for Identification of Staphylococcus delphini

2019 ◽  
Vol 57 (11) ◽  
Author(s):  
Matthew C. Canver ◽  
Tsigereda Tekle ◽  
Samantha T. Compton ◽  
Katrina Callan ◽  
Eileen M. Burd ◽  
...  
Keyword(s):  
Distinct Species ◽  
Human Infection ◽  
Species Level ◽  
Accurate Identification ◽  
Content Type ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Staphylococcus Intermedius ◽  
Animal Pathogens ◽  
Tof Ms

ABSTRACT The Staphylococcus intermedius group (SIG) is a collection of coagulase-positive staphylococci consisting of four distinct species, namely, Staphylococcus cornubiensis, Staphylococcus delphini, Staphylococcus intermedius, and Staphylococcus pseudintermedius. SIG members are animal pathogens and rare causes of human infection. Accurate identification of S. pseudintermedius has important implications for interpretation of antimicrobial susceptibility testing data and may be important for other members of the group. Therefore, we sought to evaluate the performance of five commercially available identification platforms with 21 S. delphini isolates obtained from a variety of animal and geographic sources. Here, we show that automated biochemical platforms were unable to identify S. delphini to the species level, a function of its omission from their databases, but could identify isolates to the SIG level with various degrees of success. However, all automated systems misidentified at least one isolate as Staphylococcus aureus. One matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) system was able to identify S. delphini to the species level, suggesting that MALDI-TOF MS is the best option for distinguishing members of the SIG. With the exception of S. pseudintermedius, it is unclear if other SIG members should be routinely identified to the species level; however, as our understanding of their role in animal and human diseases increases, it may be necessary and important to do so.

scholarly journals Benchmarking DNA barcodes: an assessment using available primate sequences

Genome ◽  
2006 ◽  
Vol 49 (7) ◽  
pp. 851-854 ◽  
Author(s):  
Mehrdad Hajibabaei ◽  
Gregory AC Singer ◽  
Donal A Hickey
Keyword(s):  
New Species ◽  
Cryptic Species ◽  
Dna Barcoding ◽  
Species Identification ◽  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Primate Species ◽  
Dna Barcodes ◽  
Global Biodiversity ◽  
Efficient Sequence

DNA barcoding has been recently promoted as a method for both assigning specimens to known species and for discovering new and cryptic species. Here we test both the potential and the limitations of DNA barcodes by analysing a group of well-studied organisms—the primates. Our results show that DNA barcodes provide enough information to efficiently identify and delineate primate species, but that they cannot reliably uncover many of the deeper phylogenetic relationships. Our conclusion is that these short DNA sequences do not contain enough information to build reliable molecular phylogenies or define new species, but that they can provide efficient sequence tags for assigning unknown specimens to known species. As such, DNA barcoding provides enormous potential for use in global biodiversity studies.Key words: DNA barcoding, species identification, primate, biodiversity.

scholarly journals Species Identification of Pinus Pollen Found in Belukha Glacier, Russian Altai Mountains, Using a Whole-Genome Amplification Method

Forests ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 444
Author(s):  
Fumio Nakazawa ◽  
Yoshihisa Suyama ◽  
Satoshi Imura ◽  
Hideaki Motoyama
Keyword(s):  
Species Identification ◽  
Whole Genome Amplification ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Pinus Sibirica ◽  
Whole Genome ◽  
Accurate Identification ◽  
Closely Related Species ◽  
Genome Amplification ◽  
Amplification Method

Pollen taxa in sediment samples can be identified based on morphology. However, closely related species do not differ substantially in pollen morphology, and accurate identification is generally limited to genera or families. Because many pollen grains in glaciers contain protoplasm, genetic information obtained from pollen grains should enable the identification of plant taxa at the species level. In the present study, species identification of Pinus pollen grains was attempted using whole-genome amplification (WGA). We used pollen grains extracted from surface snow (depth, 1.8–1.9 m) from the Belukha glacier in the summer of 2003. WGA was performed using a single pollen grain. Some regions of the chloroplast genome were amplified by PCR, and the DNA products were sequenced to identify the pollen grain. Pinus includes approximately 111 recognized species in two subgenera, four sections, and 11 subsections. The tree species Pinus sibirica and P. sylvestris are currently found at the periphery of the glacier. We identified the pollen grains from the Belukha glacier to the level of section or subsection to which P. sibirica and P. sylvestris belong. Moreover, we specifically identified two pollen grains as P. sibirica or P. cembra. Fifteen species, including P. sibirica, were candidates for the remaining pollen grain.

scholarly journals Bioacoustic investigations and taxonomic considerations on the Cicadetta montana species complex (Homoptera: Cicadoidea: Tibicinidae)

2004 ◽  
Vol 76 (2) ◽  
pp. 316-324 ◽  
Author(s):  
Matija Gogala ◽  
Tomi Trilar
Keyword(s):  
Cryptic Species ◽  
Species Complex ◽  
Similar Case ◽  
Genetic Differences ◽  
Species Level ◽  
Sister Species ◽  
Type Locality

Recent bioacoustic investigations have shown that Cicadetta montana Scopoli 1772 is a complex of morphologically similar sister species that are best characterized by their song patterns. At the type locality of C. montana, only mountain cicadas with simple, long lasting song phrases were heard, recorded and collected. Therefore, we have good reasons to suggest that this type of song is characteristic for C. montana s. str. Boulard described a song of C. montana from France with phrases composed of a long and a short echeme; this type of song is characteristic for cicadas morphologically corresponding to C. montana var. brevipennis Fieber 1876; we suggest to raise this taxon to species level. On the basis of specific song, Puissant and Boulard described C. cerdaniensis from Pyrénées. A similar case was the discovery and description of C. montana macedonica Schedl 1999 from Macedonia; since these Macedonian cicadas are sympatric with at least two other cryptic species in the C. montana group and molecular investigations showed substantial genetic differences between C. macedonica and C. montana or C. brevipennis, we conclude that this taxon should also be raised to species level. Songs of closely related C. podolica and Korean mountain cicada are presented as well.

scholarly journals Assessing universality of DNA barcoding in geographically isolated selected desert medicinal species of Fabaceae and Poaceae

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4499 ◽  
Author(s):  
Aisha Tahir ◽  
Fatma Hussain ◽  
Nisar Ahmed ◽  
Abdolbaset Ghorbani ◽  
Amer Jamil
Keyword(s):  
Dna Barcoding ◽  
Species Identification ◽  
Phylogenetic Trees ◽  
Sequence Similarity ◽  
Sequence Divergence ◽  
Species Level ◽  
Practical Implementation ◽  
Medicinal Species ◽  
Level Identification ◽  
Geographically Isolated

In pursuit of developing fast and accurate species-level molecular identification methods, we tested six DNA barcodes, namely ITS2, matK, rbcLa, ITS2+matK, ITS2+rbcLa, matK+rbcLa and ITS2+matK+rbcLa, for their capacity to identify frequently consumed but geographically isolated medicinal species of Fabaceae and Poaceae indigenous to the desert of Cholistan. Data were analysed by BLASTn sequence similarity, pairwise sequence divergence in TAXONDNA, and phylogenetic (neighbour-joining and maximum-likelihood trees) methods. Comparison of six barcode regions showed that ITS2 has the highest number of variable sites (209/360) for tested Fabaceae and (106/365) Poaceae species, the highest species-level identification (40%) in BLASTn procedure, distinct DNA barcoding gap, 100% correct species identification in BM and BCM functions of TAXONDNA, and clear cladding pattern with high nodal support in phylogenetic trees in both families. ITS2+matK+rbcLa followed ITS2 in its species-level identification capacity. The study was concluded with advocating the DNA barcoding as an effective tool for species identification and ITS2 as the best barcode region in identifying medicinal species of Fabaceae and Poaceae. Current research has practical implementation potential in the fields of pharmaco-vigilance, trade of medicinal plants and biodiversity conservation.

scholarly journals Proven pulmonary aspergillosis in a COVID-19 patient: A case report

2021 ◽  
Author(s):  
Sadegh Khodavaisy ◽  
Nasim Khajavirad ◽  
Seyed Jamal Hashemi ◽  
Alireza Izadi ◽  
Seyed Ali Dehghan Manshadi ◽  
...  
Keyword(s):  
Case Report ◽  
Fungal Infections ◽  
Left Lung ◽  
Aspergillus Species ◽  
Pulmonary Aspergillosis ◽  
Biopsy Material ◽  
Cavitary Lesion ◽  
Healthcare Settings ◽  
Increased Risk ◽  
History Of

Background and Purpose: Coronavirus disease 2019 (COVID-19) has become a significant clinical challenge in healthcare settings all over the world. Critically ill COVID-19 patients with acute respiratory distress syndrome may be at increased risk of co-infection with pulmonary aspergillosis. This study aimed to describe a clinical case of proven pulmonary aspergillosis caused by Aspergillus tubingensis in a 59-year-old man with a history of hospitalization due to COVID-19 infection. Case report: The Covid-19 infection was confirmed by positive nasopharyngeal polymerase chain reaction. He had a cavitary lesion measured 20 mm in diameter with intracavitary soft tissue density in the left lung in the first chest computerized tomography scan. After 25 days, he showed two cavitary lesions in both lungs which raised suspicion of fungal infection; hence, the patient underwent a trans-thoracic biopsy of the cavitary lesion. The direct examination and culture of the biopsy material revealed Aspergillus species. To confirm the Aspergillus species identification, the beta-tubulin region was sequenced. The patient was treated with oral voriconazole. Conclusion: This report underlined the importance of early diagnosis and management of invasive fungal infections in severe COVID-19 patients

scholarly journals REP-PCR analisis of single agent of cucumber bacterial diseases

2017 ◽  
Vol 15 (1) ◽  
pp. 25-31
Author(s):  
L. A. Dankevych
Keyword(s):  
Species Identification ◽  
Statistical Methods ◽  
Genetic Heterogeneity ◽  
Significant Relationship ◽  
Molecular Genetic ◽  
Single Agent ◽  
Genetic Homogeneity ◽  
Bacterial Diseases ◽  
Typical Strain ◽  
Correct Species Identification

Aim. For the purpose of correct species identification and estimation of population’s heterogeneity, the fingerprinting of the genome of isolated by us Pectobacterium sp., collection «Erwinia toxica» strains and typical representatives of certain species of Pectobacterium and Diskeya genera has been carried out. Methods. In the course of research, microbiological, molecular genetic (REP-PCR), mathematical-statistical methods of research were used. Results. On the basic of BOX, REP and ERIC profiles the significant affinity between isolated Pectobacterium sp. and collections «Erwinia toxica» strains with the typical P. carotovorum susp. carotovorum UCM B1075T has been established. Genetic heterogeneity of isolated Pectobacterium sp. and collections «Erwinia toxica» strains has been estimated. Conclusions. It has been found the significant relationship between isolates Pectobacterium sp. and the collection «Erwinia toxica» strains with the typical strain P. carotovorum susp carotovorum UCM B1075T on the basic of their BOX, REP and ERIC profiles. Most likely, this indicates that they belong to this species. The genetic homogeneity of isolated Pectobacterium sp. strains of and the genetic heterogeneity of the collection «Erwinia toxica» strains is probably due to the plant’s selection from similar or different region.Keywords: identification, genetic heterogeneity, REPPCR, «Erwinia toxica», Pectobacterium sp.

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