Clinical application of Bruker Biotyper MALDI-TOF/MS system for real-time identification of KPC production in Klebsiella pneumoniae clinical isolates

ABSTRACT Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) decreases the time to organism identification and improves clinical and financial outcomes. The purpose of this study was to evaluate the impact of MALDI-TOF MS alone versus MALDI-TOF MS combined with real-time, pharmacist-driven, antimicrobial stewardship (AMS) intervention on patient outcomes. This single-center, pre-post, quasiexperimental study evaluated hospitalized patients with positive blood cultures identified via MALDI-TOF MS combined with prospective AMS intervention compared to a control cohort with MALDI-TOF MS identification without AMS intervention. AMS intervention included: real-time MALDI-TOF MS pharmacist notification and prospective AMS provider feedback. The primary outcome was the time to optimal therapy (TTOT). A total of 252 blood cultures, 126 in each group, were included in the final analysis. MALDI-TOF MS plus AMS intervention significantly reduced the overall TTOT (75.17 versus 43.06 h; P < 0.001), the Gram-positive contaminant TTOT (48.21 versus 11.75 h; P < 0.001), the Gram-negative infection (GNI) TTOT (71.83 versus 35.98 h; P < 0.001), and the overall hospital length of stay (LOS; 15.03 versus 9.02 days; P = 0.021). The TTOT for Gram-positive infection (GPI) was improved (64.04 versus 41.61 h; P = 0.082). For GPI, the hospital LOS (14.64 versus 10.31 days; P = 0.002) and length of antimicrobial therapy 24.30 versus 18.97 days; P = 0.018) were reduced. For GNI, the time to microbiologic clearance (51.13 versus 34.51 h; P < 0.001), the hospital LOS (15.40 versus 7.90 days; P = 0.027), and the intensive care unit LOS (5.55 versus 1.19 days; P = 0.035) were reduced. To achieve optimal outcomes, rapid identification with MALDI-TOF MS combined with real-time AMS intervention is more impactful than MALDI-TOF MS alone.

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A Rapid Antimicrobial Susceptibility Test for Klebsiella pneumoniae Using a Broth Micro-Dilution Combined with MALDI TOF MS

Infection and Drug Resistance ◽

10.2147/idr.s305280 ◽

2021 ◽

Vol Volume 14 ◽

pp. 1823-1831

Author(s):

Gang Wang ◽

Guobin Song ◽

Yuanhong Xu

Keyword(s):

Klebsiella Pneumoniae ◽

Antimicrobial Susceptibility ◽

Susceptibility Test ◽

Antimicrobial Susceptibility Test ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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Black aspergilli: A remaining challenge in fungal taxonomy?

Medical Mycology ◽

10.1093/mmy/myy124 ◽

2018 ◽

Vol 57 (6) ◽

pp. 773-780 ◽

Cited By ~ 8

Author(s):

Elizabet D’hooge ◽

Pierre Becker ◽

Dirk Stubbe ◽

Anne-Cécile Normand ◽

Renaud Piarroux ◽

...

Keyword(s):

Antifungal Susceptibility ◽

Identification Accuracy ◽

Clinical Isolates ◽

Reference Database ◽

Data Set ◽

Ionization Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Tof Ms

AbstractAspergillus section Nigri is a taxonomically difficult but medically and economically important group. In this study, an update of the taxonomy of A. section Nigri strains within the BCCM/IHEM collection has been conducted. The identification accuracy of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was tested and the antifungal susceptibilities of clinical isolates were evaluated. A total of 175 strains were molecularly analyzed. Three regions were amplified (ITS, benA, and caM) and a multi-locus phylogeny of the combined loci was created by using maximum likelihood analysis. The in-house MALDI-TOF MS reference database was extended and an identification data set of 135 strains was run against a reference data set. Antifungal susceptibility was tested for voriconazole, itraconazole, and amphotericin B, using the EUCAST method. Phylogenetic analysis revealed 18 species in our data set. MALDI-TOF MS was able to distinguish between A. brasiliensis, A. brunneoviolaceus, A. neoniger, A. niger, A. tubingensis, and A. welwitschiae of A. sect. Nigri. In the routine clinical lab, isolates of A. sect. Nigri are often identified as A. niger. However, in the clinical isolates of our data set, A. tubingensis (n = 35) and A. welwitschiae (n = 34) are more common than A. niger (n = 9). Decreased antifungal susceptibility to azoles was observed in clinical isolates of the /tubingensis clade. This emphasizes the importance of identification up to species level or at least up to clade level in the clinical lab. Our results indicate that MALDI-TOF MS can be a powerful tool to replace classical morphology.

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Cytosolic Proteome Profiling of Aminoglycosides Resistant Mycobacterium tuberculosis Clinical Isolates Using MALDI-TOF/MS

Frontiers in Microbiology ◽

10.3389/fmicb.2016.01816 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 23

Author(s):

Divakar Sharma ◽

Manju Lata ◽

Rananjay Singh ◽

Nirmala Deo ◽

Krishnamurthy Venkatesan ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Clinical Isolates ◽

Maldi Tof Ms ◽

Proteome Profiling ◽

Maldi Tof ◽

Tof Ms

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Implementation of MALDI-TOF MS technology for the identification of clinical isolates of Mycobacterium spp. in mycobacterial diagnosis

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-015-2381-2 ◽

2015 ◽

Vol 34 (8) ◽

pp. 1527-1532 ◽

Cited By ~ 20

Author(s):

G. Tudó ◽

M. R. Monté ◽

A. Vergara ◽

A. López ◽

J. C. Hurtado ◽

...

Keyword(s):

Clinical Isolates ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms ◽

Mycobacterium Spp

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Occurrence of the p019 gene in the blaKPC-harbouring plasmids: adverse clinical impact for direct tracking of KPC-producing Klebsiella pneumoniae by MALDI-TOF MS

Journal of Clinical Microbiology ◽

10.1128/jcm.00238-21 ◽

2021 ◽

Author(s):

Eva Gato ◽

Ignacio Pedro Constanso ◽

Bruno Kotska Rodiño-Janeiro ◽

Paula Guijarro-Sánchez ◽

Tyler Alioto ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Computational Analysis ◽

Direct Detection ◽

Clinical Impact ◽

Mass Peak ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Direct Tracking ◽

Geographical Locations ◽

Tof Ms

MALDI-TOF MS has recently been used for the direct detection of KPC-producing isolates by analysis of the 11,109 Da mass peak representing the P019 protein. In this study we evaluate the presence of the 11,109 Da mass peak in a collection of 435 unduplicated K. pneumoniae clinical isolates. The prevalence of the P019 peak in the blaKPC K. pneumoniae isolates was 49.2% (32/65). The 11,109 Da mass peak was not observed in any of the other carbapenemase (319) or non carbapenemase producers (116). Computational analysis of the presence of the p019 gene was performed in the aforementioned carbapenemase-producing K. pneumoniae isolates fully characterized by WGS and in a further collection of 1,649 K. pneumoniae genomes included in EuSCAPE. Herein, we have demonstrated that the p019 gene is not exclusively linked to the pKpQil plasmid, but it is present in the following plasmids: IncFIB(K)/IncFII(K)/ColRNAI, IncFIB(pQil), IncFIB(pQil)/ColRNAI, IncFIB(pQil)/IncFII(K), IncFIB(K)/IncFII(K) and IncX3. Besides, we have proven the independent movement of the Tn4401 and the ISKpn31, of which the p019 gene is a component. The absence of the p019 gene was obvious in Col440I, Col(pHAD28), IncFIB(K)/IncX3/IncFII(K), IncFIB(K)/IncFII(K) plasmids. In addition, we also observed another plasmid in which neither Tn4401 nor ISKpn31 was found, IncP6. In the EuSCAPE, the occurrence of p019 varied from 0% to 100% among the different geographical locations. The adverse clinical impact of the diminished prevalence of the p019 gene within the plasmid encoding KPC-producing Klebsiella pneumoniae puts forward the need for reconsideration when applying this technique in a clinical setting.

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Real‐time PCR versus MALDI‐TOF MS and culture‐based techniques for diagnosis of bloodstream and pyogenic infections in humans and animals

Journal of Applied Microbiology ◽

10.1111/jam.14862 ◽

2020 ◽

Author(s):

N.K. Abd El‐Aziz ◽

A.A Gharib ◽

E.A.A. Mohamed ◽

A.H. Hussein

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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Clinical and microbiological characteristics of Cryptococcus gattii isolated from China

10.21203/rs.2.21273/v1 ◽

2020 ◽

Author(s):

Liang Jin ◽

Jingrong Cao ◽

Xinying Xue ◽

Hua Wu ◽

Lifeng Wang ◽

...

Keyword(s):

Antifungal Agents ◽

Antifungal Susceptibility ◽

The United States ◽

Cryptococcus Gattii ◽

Clinical Isolates ◽

Strain Identification ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Significant Difference ◽

Tof Ms

Abstract Background: Infection, even outbreak, caused by Cryptococcus gattii (C. gattii ) has been reported in Canada and the United States, but there were sparsely-reported cases of C. gattii in China. Our interest in occurrence, clinical manifestation, laboratory identification and molecular characterization of Chinese C. gattii strains leads us to this research. Methods: A total of 254 clinical isolates primarily identified as Cryptococcus neoformans (C. neoformans ) were collected. VITEK 2 compact, canavanine glycine bromothymol blue (CGB) agar and Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used for strain identification. Multi-locus sequence typing (MLST) was performed for genotyping. Antifungal susceptibility test was carried out with commercial kits of both ATB fungus 3 and Yeast one. Clinical information of patients was reviewed retrospectively. Label-free proteome technique was used to quantitatively analyze the differential proteins of C. gattii. Results: Out of 254 clinical isolates, we identified eight strains as C. gattii. MLST showed genotype VGI accounted for the most (6 / 8), the other two strains were genotype VGII（VGIIa and VGIIb respectively）with 3 specific spectra of molecular weight about 4342, 8686, 9611 Dalton by MALDI-TOF MS. The minimal inhibitory concentrations (MICs) of Fluconazole with Yeast one was 2～4 times higher than that with ATB fungus 3. Higher MICs of antifungal agents were exhibited against VGII strains than against VGI strains. C. gattii genotype VGII and VGI possessed 418 and 774 specific proteins respectively. Comparative proteome analysis showed that 180 proteins were highly expressed in C. gattii VGII and 329 proteins were highly expressed in C. gattii VGI. The enrichment of differentially expressed proteins between VGII and VGI was directed to Golgi complex.Conclusions: Infection by C. gattii in China might have been underestimated because of initial mis-identification. Genotype VGI was predominant but VGII was more resistant to antifungal agents. There was significant difference in protein expression profile between VGII and VGI C. gattii.

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