Identification of fungal isolates by MALDI-TOF mass spectrometry in veterinary practice: validation of a web application

Becker, Pierre; Normand, Anne‐Cécile; Vanantwerpen, Gerty; Vanrobaeys, Mia; Haesendonck, Roel; Vercammen, Francis; Stubbe, Dirk; Piarroux, Renaud; Hendrickx, Marijke

doi:10.1177/1040638719835577

Cited by 16 publications

(14 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Some studies described that decreasing the species cut‐off to 1.7 increased species identification level without leading to misidentification 13,32,33 . We can observe the same fact in our study so the cut‐off value for results was set at 1.7, and we encourage other laboratories to use the same cut‐off to improve correct fungal identification by MALDI‐TOF MS.…”

Section: Discussionsupporting

confidence: 73%

Evaluation of the new Id‐Fungi plates from Conidia for MALDI‐TOF MS identification of filamentous fungi and comparison with conventional methods as identification tool for dermatophytes from nails, hair and skin samples

Sacheli¹,

Henri²,

Seidel

et al. 2020

Mycoses

View full text Add to dashboard Cite

Objectives We first compare the efficiency of mould/dermatophyte identification by MALDI‐TOF MS using a new medium called Id‐Fungi plates (IDFP) from Conidia® and two different databases. For the second purpose, we evaluated a new version of the medium supplemented with cycloheximide, Id‐Fungi plates Plus (IDFPC) for the direct inoculation of nails, hair and skin samples and compared the efficiency of MALDI‐TOF MS identification of dermatophytes to classical methods based on culture and microscopy. Methods A total of 71 strains have been cultured IDFP and Sabouraud gentamicin plates (SGC2) and were identified by MALDI‐TOF MS. For the evaluation of the combination IDFPC/ MALDI‐TOF MS as a method of identification for dermatophytes, 428 samples of hair nails and skin were cultivated in parallel on IDFPC and Sabouraud + cycloheximide medium (SAB‐ACTI). Results For Aspergillus sp and non‐Aspergillus moulds, the best performances were obtained on IDFP after maximum 48‐h growth, following protein extraction. For dermatophytes, the best condition was using the IDFP at 72 hours, after extended direct deposit. Regarding the direct inoculation of nails, hair skin on IDFPC, 129/428 (30.1%) showed a positive culture against 150/428 (35%) on SAB‐ACTI medium. Among the 129 positive strains, the identification by MALDI‐TOF MS was correct for 92/129 (71.4%). Conclusion The IDFP allows the generation of better spectra by MALDI‐TOF MS compared to SGC2. It facilitates sampling and deposit. Regarding the use of IDFPC, this medium seems less sensitive than SAB‐ACTI but among positive strains, the rate of correct identification by MALDI‐TOF MS is satisfactory.

show abstract

Section: Discussionsupporting

confidence: 73%

Evaluation of the new Id‐Fungi plates from Conidia for MALDI‐TOF MS identification of filamentous fungi and comparison with conventional methods as identification tool for dermatophytes from nails, hair and skin samples

Sacheli¹,

Henri²,

Seidel

et al. 2020

Mycoses

View full text Add to dashboard Cite

show abstract

“…MALDI-TOF MS is an excellent tool for the rapid and accurate identification of molds (Alanio et al, 2011; Cassagne et al, 2011; Theel et al, 2011; Alshawa et al, 2012; De Carolis et al, 2012; Del Chierico et al, 2012; Schrodl et al, 2012; de Respinis et al, 2013; Lau et al, 2013; L’Ollivier et al, 2013; Nenoff et al, 2013; Normand et al, 2013, 2017; Barker et al, 2014; Becker et al, 2014, 2019; Gautier et al, 2014; Ranque et al, 2014; Sitterle et al, 2014; Dolatabadi et al, 2015; Triest et al, 2015; Sleiman et al, 2016; Stein et al, 2018; Dupont et al, 2019), yet its wider application in the clinical setting has been extremely limited, in part due to limited database availability and lack of standardized processes. Here, we evaluated the versatility of the NIH Mold Database (Lau et al, 2013) across 10 centers each with varying levels of mass spectrometry experience with molds, using a set of 80 challenge isolates that encompassed common clinical molds and less common organisms (Table 1).…”

Section: Discussionmentioning

confidence: 99%

Multicenter Study Demonstrates Standardization Requirements for Mold Identification by MALDI-TOF MS

et al. 2019

View full text Add to dashboard Cite

ObjectivesRapid and accurate mold identification is critical for guiding therapy for mold infections. MALDI-TOF MS has been widely adopted for bacterial and yeast identification; however, few clinical laboratories have applied this technology for routine mold identification due to limited database availability and lack of standardized processes. Here, we evaluated the versatility of the NIH Mold Database in a multicenter evaluation.MethodsThe NIH Mold Database was evaluated by eight US academic centers using a solid media extraction method and a challenge set of 80 clinical mold isolates. Multiple instrument parameters important for spectra optimization were evaluated, leading to the development of two specialized acquisition programs (NIH method and the Alternate-B method).ResultsA wide range in performance (33–77%) was initially observed across the eight centers when routine spectral acquisition parameters were applied. Use of the NIH or the Alternate-B specialized acquisition programs, which are different than those used routinely for bacterial and yeast spectral acquisition (MBT_AutoX), in combination with optimized instrument maintenance, improved performance, illustrating that acquisition parameters may be one of the key limiting variable in achieving successful performance.ConclusionSuccessful mold identification using the NIH Database for MALDI-TOF MS on Biotyper systems was demonstrated across multiple institutions for the first time following identification of critical program parameters combined with instrument optimization. This significantly advances our potential to implement MALDI-TOF MS for mold identification across many institutions. Because instrument variability is inevitable, development of an instrument performance standard specific for mold spectral acquisition is suggested to improve reproducibility across instruments.

show abstract

“…Despite these limitations, MALDI‐TOF MS has been proven to be a rapid and reliable method for the identification of pathogens directly from blood culture bottles. The technique is inexpensive, the identification can be completed within 1 hour, and specialized personnel is not required …”

Section: Discussionmentioning

confidence: 99%

Evaluation of an optimized method to directly identify bacteria from positive blood cultures using MALDI‐TOF mass spectrometry

Yuan

Wang²,

Zhang

et al. 2019

Clinical Laboratory Analysis

View full text Add to dashboard Cite

Background: Although various methods have been developed to directly identify bacteria from positive blood cultures by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), the necessity of using commercial kits still leads to a high cost and long assay time. Moreover, few evaluations of these methods have been conducted. This study aimed to evaluate the feasibility of an optimized MALDI-TOF MS method for direct identification of bacteria in positive blood cultures. Methods: A total of 829 non-repeated positive cultures were collected from July 2018 to August 2019, and direct identification was performed by an optimized MALDI-TOF MS method. The same positive blood cultures were sub-cultivated to obtain a single bacterial colony and identified by classical biochemical BD testing, which is the gold standard to compare the accuracy of direct identification of positive blood cultures by MALDI-TOF MS.Results: After excluding 7 false-positive samples from the 829 positive blood cultures, the most accurate rate of direct identification by this optimized MALDI-TOF MS method was for gram-negative bacteria (91.5%), followed by gram-positive bacteria (88.3%), fungi (84.8%), anaerobic bacteria (80%), and other rare bacteria (66.67%). Conclusion:Common bacteria in positive blood cultures can be identified directly within 1 hour by MALDI-TOF MS, and thus, this optimized method can be used as a primary identification method by clinicians. Routine implementation of this method may significantly increase the optimal utilization rate of antibiotics and decrease mortality in bacteremia patients. K E Y W O R D S bacteria, blood culture, identification, MALDI-TOF MS S U PP O RTI N G I N FO R M ATI O N Additional supporting information may be found online in the Supporting Information section.Evaluation of an optimized method to directly identify bacteria from positive blood cultures using MALDI-TOF mass spectrometry. J Clin Lab Anal. 2020;34:e23119. https ://doi.

show abstract

Identification of fungal isolates by MALDI-TOF mass spectrometry in veterinary practice: validation of a web application

Cited by 16 publications

References 21 publications

Evaluation of the new Id‐Fungi plates from Conidia for MALDI‐TOF MS identification of filamentous fungi and comparison with conventional methods as identification tool for dermatophytes from nails, hair and skin samples

Evaluation of the new Id‐Fungi plates from Conidia for MALDI‐TOF MS identification of filamentous fungi and comparison with conventional methods as identification tool for dermatophytes from nails, hair and skin samples

Multicenter Study Demonstrates Standardization Requirements for Mold Identification by MALDI-TOF MS

Evaluation of an optimized method to directly identify bacteria from positive blood cultures using MALDI‐TOF mass spectrometry

Contact Info

Product

Resources

About