Chung-Ang University researchers evaluate mass spectrometry approaches for mold identification - EurekAlert

In caller years, filamentous fungi oregon molds person emerged arsenic causative agents underlying life-threatening infections successful immunocompromised individuals. The timely absorption of these infections requires the accelerated and close diagnosis of mold successful objective settings.

Unfortunately, accepted methods are clip consuming, fixed the agelong incubation periods required to civilization and analyse molds. On the different hand, precocious molecular techniques are much delicate and efficient. One specified method that tin observe filamentous fungal isolates with high-sensitivity and reproducibility, is “matrix-assisted laser desorption ionization-time of formation wide spectrometry (MALDI-TOF MS)”. It tin differentiate betwixt samples based connected variations successful wide and charge. However, it is not wide utilized owed to limitations successful database availability and a deficiency of standardized procedures.

Recently, a squad of researchers from Chung-Ang University, Republic of Korea led by Professor Mi-Kyung Lee, evaluated 3 antithetic MALDI-TOF MS approaches utilized successful home objective settings, for the recognition of molds.

In their study published successful The Journal of Clinical Microbiology on October 26, 2022, they compared the show and diagnostic accuracy of the Bruker Biotyper, ASTA MicroIDSys, and Vitek MS. They besides assessed the sensitivity of 3 pretreatment methods— “direct”, “on plate”, and “in tube”—using 84 filamentous fungal isolates. 

Explaining the rationale down their study, Prof. Lee remarks, “Selecting an due illustration mentation method tin amended the ratio and accuracy of mold identification. Additionally, the improvement of systemized processes astatine the diagnostic level tin yet lend to effectual treatments for patients”

The survey recovered that the Bruker Biotyper identified 71.43% of isolates correctly up to the taxon oregon genus level, portion ASTA MicroIDSys and Vitek MS demonstrated accuracy rates of 70.24% and 55.95%, respectively. Furthermore, the nonstop method for illustration mentation was favorable implicit the different 2 methods, owing to its simplicity and easiness of application. Notably, recognition sensitivity did not disagree importantly crossed antithetic illustration mentation methods.

The complaint of misidentification is an important information successful objective laboratories due to the fact that it tin pb to inappropriate attraction interventions for patients. In this study, lone 1 isolate was misidentified utilizing Vitek-MS with the on-plate method. Moreover, the taxon level recognition of Aspergillus (a highly prevalent and clinically important microorganism) was highest done Vitek-MS, indicating the applicability of this method successful objective settings.

The fig of incorrectly identified taxon were 17, 15, and 23 done the Bruker Biotyper, ASTA MicroIDSys, and Vitek MS, respectively. The squad suggested the request for further evaluations if misidentification occurred owed to the lack of definite taxon successful the room alternatively than an error. Furthermore, the squad determined that immoderate differences successful sensitivity could beryllium attributed to differences successful the strategy databases. 

In summary, MALDI-TOF MS is simply a invaluable method that tin accurately place clinically important microorganisms successful a timely manner. Process standardization and guidelines that tin beryllium applied to a wide scope of taxon tin assistance trim the process bias occurring done these techniques. Additionally, limitations related to acquisition parameters, matrix quality, and hardware necessitate further assessments.

When asked astir the applications of the study, Prof. Lee says, “Our survey is the archetypal to comparison the sensitivity and accuracy of 3 MALDI-TOF MS instruments arsenic good arsenic the efficacy of 3 pretreatment methods for filamentous fungal identification. Accurate results obtained done a elemental and streamlined process for mold recognition utilizing MALDI-TOF MS could amended laboratory enactment ratio for users and attraction ratio for patients.”

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Reference

DOI: https://doi.org/10.1128/jcm.00812-22

Authors: Yoojeong Choi^a, Daewon Kim^b, Kye Won Choe^a, Hyukmin Lee^c, Jae-Seok Kim^d, Jeong-Yeal Ahn^b, and Mi-Kyung Lee^a

Affiliations:

^aDepartment of Laboratory Medicine, Chung-Ang University College of Medicine, Seoul, Republic of Korea

^bDepartment of Laboratory Medicine, Gachon University Gil Medical Center, Incheon, Republic of Korea

^cDepartment of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Republic of Korea

^dDepartment of Laboratory Medicine, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Republic of Korea

About Chung-Ang University

Chung-Ang University is simply a backstage broad probe assemblage located successful Seoul, South Korea. It was started arsenic a kindergarten successful 1916 and attained assemblage presumption successful 1953. It is afloat accredited by the Ministry of Education of Korea. Chung-Ang University conducts probe activities nether the slogan of “Justice and Truth.” Its caller imaginativeness for completing 100 years is “The Global Creative Leader.” Chung-Ang University offers undergraduate, postgraduate, and doctoral programs, which encompass a instrumentality school, absorption program, and aesculapian school; it has 16 undergraduate and postgraduate schools each. Chung-Ang University’s civilization and arts programs are considered the champion successful Korea.

Website: https://neweng.cau.ac.kr/index.do

About Professor Mi-Kyung Lee from Chung-Ang University

Dr. Mi-Kyung Lee is a prof astatine the Department of Laboratory Medicine astatine Chung-Ang University College of Medicine. She holds a PhD in Laboratory Medicine and has implicit 230 publications to her credit. With a probe acquisition spanning implicit 2 decades successful the fields of objective microbiology and molecular genetics, her probe is presently focused connected fungal infections and antifungal cause susceptibility. With the enactment of the Korean Science and Engineering Foundation, she has successfully completed a 1-year grooming fellowship successful the Mycotic Disease Branch, Centers for Disease Control and Prevention successful Atlanta, Georgia, USA successful 2002, pursuing which she consistently conducts epidemiological and molecular studies of objective microorganisms (particularly the Candida species) successful South Korea.