scholarly journals Rapid identification of respiratory bacterial pathogens from bronchoalveolar lavage fluid in cattle by MALDI-TOF MS

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Laura Van Driessche ◽  
Jade Bokma ◽  
Piet Deprez ◽  
Freddy Haesebrouck ◽  
Filip Boyen ◽  
...  
Keyword(s):  
Bronchoalveolar Lavage ◽  
Bronchoalveolar Lavage Fluid ◽  
Lavage Fluid ◽  
Turnaround Time ◽  
Rapid Identification ◽  
Antimicrobial Use ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tract Infections ◽  
Tof Ms

AbstractRespiratory tract infections are a major health problem and indication for antimicrobial use in cattle and in humans. Currently, most antimicrobial treatments are initiated without microbiological results, holding the risk of inappropriate first intention treatment. The main reason for this empirical treatment is the long turnaround time between sampling and availability of identification and susceptibility results. Therefore the objective of the present study was to develop a rapid identification procedure for pathogenic respiratory bacteria in bronchoalveolar lavage fluid (BALf) samples from cattle by MALDI-TOF MS, omitting the cultivation step on agar plates to reduce the turnaround time between sampling and identification of pathogens. The effects of two different liquid growth media and various concentrations of bacitracin were determined to allow optimal growth of Pasteurellaceae and minimise contamination. The best procedure was validated on 100 clinical BALf samples from cattle with conventional bacterial culture as reference test. A correct identification was obtained in 73% of the samples, with 59.1% sensitivity (Se) (47.2–71.0%) and 100% specificity (Sp) (100–100%) after only 6 hours of incubation. For pure and dominant culture samples, the procedure was able to correctly identify 79.2% of the pathogens, with a sensitivity (Se) of 60.5% (45.0–76.1%) and specificity (Sp) of 100% (100–100%). In mixed culture samples, containing ≥2 clinically relevant pathogens, one pathogen could be correctly identified in 57% of the samples with 57.1% Se (38.8–75.5%) and 100% Sp (100–100%). In conclusion, MALDI-TOF MS is a promising tool for rapid pathogen identification in BALf. This new technique drastically reduces turnaround time and may be a valuable decision support tool to rationalize antimicrobial use.

scholarly journals Rapid identification of Legionella species by mass spectrometry

2010 ◽  
Vol 59 (3) ◽  
pp. 273-284 ◽  
Author(s):  
Claire Moliner ◽  
Christophe Ginevra ◽  
Sophie Jarraud ◽  
Christophe Flaudrops ◽  
Marielle Bedotto ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Bacterial Species ◽  
Rapid Identification ◽  
Species Level ◽  
Blind Test ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tract Infections ◽  
Pcr Targeting ◽  
Tof Ms

Legionella species are facultative, intracellular bacteria that infect macrophages and protozoa, with the latter acting as transmission vectors to humans. These fastidious bacteria mostly cause pulmonary tract infections and are routinely identified by various molecular methods, mainly PCR targeting the mip gene and sequencing, which are expensive and time-consuming. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has emerged as a rapid and inexpensive method for identification of bacterial species. This study evaluated the use of MALDI-TOF-MS for rapid species and serogroup identification of 21 Legionella species recognized as human pathogens. To this end, a reference MS database was developed including 59 Legionella type strains, and a blind test was performed using 237 strains from various species. Two hundred and twenty-three of the 237 strains (94.1 %) were correctly identified at the species level, although ten (4.2 %) were identified with a score lower than 2.0. Fourteen strains (5.9 %) from eight species were misidentified at the species level, including seven (3.0 %) with a significant score, suggesting an intraspecific variability of protein profiles within some species. MALDI-TOF-MS was reproducible but could not identify Legionella strains at the serogroup level. When compared with mip gene sequencing, MALDI-TOF-MS exhibited a sensitivity of 99.2 and 89.9 % for the identification of Legionella strains at the genus and species level, respectively. This study demonstrated that MALDI-TOF-MS is a reliable tool for the rapid identification of Legionella strains at the species level.

scholarly journals Rapid Identification of Mycoplasma bovis Strains from Bovine Bronchoalveolar Lavage Fluid with Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry after Enrichment Procedure

2020 ◽  
Vol 58 (6) ◽  
Author(s):  
Jade Bokma ◽  
Laura Van Driessche ◽  
Piet Deprez ◽  
Freddy Haesebrouck ◽  
Marianne Vahl ◽  
...  
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Lavage Fluid ◽  
Rapid Identification ◽  
Ionization Time ◽  
Content Type ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Tof Ms

ABSTRACT Mycoplasma bovis is a leading cause of pneumonia in modern calf rearing. Fast identification is essential to ensure appropriate antimicrobial therapy. Therefore, the objective of this study was to develop a protocol to identify M. bovis from bronchoalveolar lavage fluid (BALf) with matrix-assisted laser desorption ionization–time of flight mass spectrometry MALDI-TOF MS and to determine the diagnostic accuracy in comparison with other techniques. BALf was obtained from 104 cattle, and the presence of M. bovis was determined in the following three ways: (i) rapid identification of M. bovis with MALDI-TOF MS (RIMM) (BALf was enriched and after 24, 48, and 72 h of incubation and was analyzed using MALDI-TOF MS), (ii) triplex real-time PCR for M. bovis, Mycoplasma bovirhinis, and Mycoplasma dispar, and (iii) 10-day incubation on selective-indicative agar. The diagnostic accuracy of the three tests was determined with Bayesian latent class modeling (BLCM). After 24 h of enrichment, M. bovis was identified with MALDI-TOF MS in 3 out of 104 BALf samples. After 48 and 72 h of enrichment, 32/104 and 38/100 samples, respectively, were M. bovis positive. Lipase-positive Mycoplasma-like colonies were seen in 28 of 104 samples. Real-time PCR resulted in 28/104 positive and 12/104 doubtful results for M. bovis. The BLCM showed a sensitivity (Se) and specificity (Sp) of 86.6% (95% credible interval [CI], 69.4% to 97.6%) and 86.4% (CI, 76.1 to 93.8) for RIMM. For real-time PCR, Se was 94.8% (CI, 89.9 to 97.9) and Sp was 88.9% (CI, 78.0 to 97.4). For selective-indicative agar, Se and Sp were 70.5% (CI, 52.1 to 87.1) and 93.9% (CI, 85.9 to 98.4), respectively. These results suggest that rapid identification of M. bovis with MALDI-TOF MS after an enrichment procedure is a promising test for routine diagnostics in veterinary laboratories.

Automation and validation of a MALDI-TOF MS (Mass-Fix) replacement of immunofixation electrophoresis in the clinical lab

2021 ◽  
Vol 59 (1) ◽  
pp. 155-163
Author(s):  
Mindy Kohlhagen ◽  
Surendra Dasari ◽  
Maria Willrich ◽  
MeLea Hetrick ◽  
Brian Netzel ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Turnaround Time ◽  
Automated System ◽  
Serum Samples ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Automated Method ◽  
Positive Specimen ◽  
Specimen Identification ◽  
Tof Ms

AbstractObjectivesA matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) method (Mass-Fix) as a replacement for gel-based immunofixation (IFE) has been recently described. To utilize Mass-Fix clinically, a validated automated method was required. Our aim was to automate the pre-analytical processing, improve positive specimen identification and ergonomics, reduce paper data storage and increase resource utilization without increasing turnaround time.MethodsSerum samples were batched and loaded onto a liquid handler along with reagents and a barcoded sample plate. The pre-analytical steps included: (1) Plating immunopurification beads. (2) Adding 10 μl of serum. (3) Bead washing. (4) Eluting the immunoglobulins (Igs), and reducing to separate the heavy and light Ig chains. The resulting plate was transferred to a second low-volume liquid handler for MALDI plate spotting. MALDI-TOF mass spectra were collected. Integrated in-house developed software was utilized for sample tracking, driving data acquisition, data analysis, history tracking, and result reporting. A total of 1,029 residual serum samples were run using the automated system and results were compared to prior electrophoretic results.ResultsThe automated Mass-Fix method was capable of meeting the validation requirements of concordance with IFE, limit of detection (LOD), sample stability and reproducibility with a low repeat rate. Automation and integrated software allowed a single user to process 320 samples in an 8 h shift. Software display facilitated identification of monoclonal proteins. Additionally, the process maintains positive specimen identification, reduces manual pipetting, allows for paper free tracking, and does not significantly impact turnaround time (TAT).ConclusionsMass-Fix is ready for implementation in a high-throughput clinical laboratory.

scholarly journals Yupingfeng Pulvis Regulates the Balance of T Cell Subsets in Asthma Mice

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Zhigang Wang ◽  
Xueting Cai ◽  
Zhonghua Pang ◽  
Dawei Wang ◽  
Juan Ye ◽  
...  
Keyword(s):  
Bronchoalveolar Lavage ◽  
Th17 Cells ◽  
Bronchoalveolar Lavage Fluid ◽  
Lavage Fluid ◽  
Treg Cells ◽  
T Cell Subsets ◽  
Control Group ◽  
Group Model ◽  
Therapy Effect ◽  
Tract Infections

Background. Yupingfeng Pulvis (HFBP) had played an active role in many diseases, especially respiratory tract infections. Exploring the possible prevention mechanism of HFBP may provide new ideas in clinical applications for this well-known herbal formula.Purpose. To study the possible mechanisms of therapy effect of HFBP on asthma mice via regulating the balance of Tregs and Th17 cells.Method. The female BALB/c mice were divided into five groups: control group, model group, prednisone (5.5 mg/kg) group, and 22 g/kg HFBP and 44 g/kg HFBP groups. Ovalbumin was used to make the asthma model of mice; the drug was ig administered daily after atomization for consecutive 15 d. The mice were killed after the last administration. The paraffin-embedded tissue sections of the lungs were stained by H&E. Tregs and Th17 cells in bronchoalveolar lavage fluid were detected by flow cytometry. IL-4, TGF-β, and TNF-αin the serum were detected by ELISA assay.Results. HFBP could alleviate the inflammation in the lung tissue of mice, decrease the proportion of Th17 cells, and increase the proportion of Treg cells in bronchoalveolar lavage fluid. HFBP could decrease IL-4 and TNF-αlevel and increase TGF-βlevel in blood.Conclusion. HFBP could treat the asthma through impacting the balance of Th17 cells and Treg cells as well as the levels of related inflammatory cytokines in asthma mice.

scholarly journals Establishment and Application of Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry for Detection of Shewanella Genus

2021 ◽  
Vol 12 ◽  
Author(s):  
Keyi Yu ◽  
Zhenzhou Huang ◽  
Ying Li ◽  
Qingbo Fu ◽  
Lirong Lin ◽  
...  
Keyword(s):  
Laser Desorption ◽  
Rapid Identification ◽  
Species Level ◽  
Laser Desorption Ionization ◽  
Ionization Time ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Type Strains ◽  
Tof Ms

Shewanella species are widely distributed in the aquatic environment and aquatic organisms. They are opportunistic human pathogens with increasing clinical infections reported in recent years. However, there is a lack of a rapid and accurate method to identify Shewanella species. We evaluated here matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for rapid identification of Shewanella. A peptide mass reference spectra (PMRS) database was constructed for the type strains of 36 Shewanella species. The main spectrum projection (MSP) cluster dendrogram showed that the type strains of Shewanella species can be effectively distinguished according to the different MS fingerprinting. The PMRS database was validated using 125 Shewanella test strains isolated from various sources and periods; 92.8% (n = 116) of the strains were correctly identified at the species level, compared with the results of multilocus sequence analysis (MLSA), which was previously shown to be a method for identifying Shewanella at the species level. The misidentified strains (n = 9) by MALDI-TOF MS involved five species of two groups, i.e., Shewanella algae–Shewanella chilikensis–Shewanella indica and Shewanella seohaensis–Shewanella xiamenensis. We then identified and defined species-specific biomarker peaks of the 36 species using the type strains and validated these selected biomarkers using 125 test strains. Our study demonstrated that MALDI-TOF MS was a reliable and powerful tool for the rapid identification of Shewanella strains at the species level.

scholarly journals Rapid identification of Streptomyces isolates by MALDI-TOF MS

2014 ◽  
Vol 169 (12) ◽  
pp. 940-947 ◽  
Author(s):  
Lotfi Loucif ◽  
Esma Bendjama ◽  
Djamila Gacemi-Kirane ◽  
Jean-Marc Rolain
Keyword(s):  
Rapid Identification ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

scholarly journals Prospective Evaluation of Light Scatter Technology Paired with Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry for Rapid Diagnosis of Urinary Tract Infections

2017 ◽  
Vol 55 (6) ◽  
pp. 1802-1811 ◽  
Author(s):  
Sandra Montgomery ◽  
Kiana Roman ◽  
Lan Ngyuen ◽  
Ana Maria Cardenas ◽  
James Knox ◽  
...  
Keyword(s):  
Susceptibility Testing ◽  
Automated System ◽  
Light Scatter ◽  
Laser Desorption Ionization ◽  
Ionization Time ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tract Infections ◽  
Organism Identification ◽  
Tof Ms

ABSTRACTUrinary tract infections are one of the most common reasons for health care visits. Diagnosis and optimal treatment often require a urine culture, which takes an average of 1.5 to 2 days from urine collection to results, delaying optimal therapy. Faster, but accurate, alternatives are needed. Light scatter technology has been proposed for several years as a rapid screening tool, whereby negative specimens are excluded from culture. A commercially available light scatter device, BacterioScan 216Dx (BacterioScan, Inc.), has recently been advertised for this application. Paired use of mass spectrometry (MS) for bacterial identification and automated-system-based susceptibility testing straight from the light scatter suspension might provide dramatic improvement in times to a result. The present study prospectively evaluated the BacterioScan device, with culture as the reference standard. Positive light scatter specimens were used for downstream rapid matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) MS organism identification and automated-system-based antimicrobial susceptibility testing. Prospective evaluation of 439 urine samples showed a sensitivity of 96.5%, a specificity of 71.4%, and positive and negative predictive values of 45.1% and 98.8%, respectively. MALDI-TOF MS analysis of the suspension after density-based selection yielded a sensitivity of 72.1% and a specificity of 96.9%. Antimicrobial susceptibility testing of the samples identified by MALDI-TOF MS produced an overall categorical agreement of 99.2%. Given the high sensitivity and negative predictive value of results obtained, BacterioScan 216Dx is a reasonable approach for urine screening and might produce negative results in as few as 3 h, with no downstream workup. Paired rapid identification and susceptibility testing might be useful when MALDI-TOF MS results in an organism identification, and it might decrease the time to a result by more than 24 h.

scholarly journals Rapid Identification of Microorganisms from Positive Blood Culture by MALDI-TOF MS After Short-Term Incubation on Solid Medium

2016 ◽  
Vol 74 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Antonio Curtoni ◽  
Raffaella Cipriani ◽  
Elisa Simona Marra ◽  
Anna Maria Barbui ◽  
Rossana Cavallo ◽  
...  
Keyword(s):  
Blood Culture ◽  
Positive Blood Culture ◽  
Solid Medium ◽  
Rapid Identification ◽  
Short Term ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms
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