Dataset Information

The Use of MALDI-TOF Mass Spectrometry to Analyze Commensal Oral Yeasts in Nursing Home Residents.

ABSTRACT: Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate method to identify microorganisms in clinical laboratories. This study isolates yeast-like microorganisms in the oral washes that are collected from non-bedridden nursing home residents, using CHROMagar Candida plates, and identifies them using Bruker MALDI-TOF MS. The ribosomal DNA sequences of the isolates are then examined. Three hundred and twenty yeast isolates are isolated from the oral washes. Candida species form the majority (78.1%), followed by Trichosporon/Cutaneotrichosporon species (8.8%). Bruker MALDI-TOF MS gives a high-level confidence, with a log(score) value of ?1.8, and identifies 96.9% of the isolates. There are six inconclusive results (1.9%), and those sequences are verified as rare clinical species, including Candida ethanolica, Cutaneotrichosporon jirovecii, Exophiala dermatitidis, and Fereydounia khargensis. Almost all of the isolates have a regular color on the CHROMagar Candida plates. If the colonies are grouped by color on the plates, a specific dominant yeast species is present in each color group, except for purple or orange isolates. In conclusion, MALDI-TOF MS is verified as a fast, accurate and practical method to analyze oral yeasts in elderly subjects.

SUBMITTER: Lu JJ

PROVIDER: S-EPMC7828027 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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The Use of MALDI-TOF Mass Spectrometry to Analyze Commensal Oral Yeasts in Nursing Home Residents.

Lu Jang-Jih JJ Lo Hsiu-Jung HJ Lee Chih-Hua CH Chen Mei-Jun MJ Lin Chih-Chao CC Chen Yin-Zhi YZ Tsai Ming-Horng MH Wang Shao-Hung SH

Microorganisms 20210109 1

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate method to identify microorganisms in clinical laboratories. This study isolates yeast-like microorganisms in the oral washes that are collected from non-bedridden nursing home residents, using CHROMagar <i>Candida</i> plates, and identifies them using Bruker MALDI-TOF MS. The ribosomal DNA sequences of the isolates are then examined. Three hundred and twenty yeast isolates are isol ...[more]

PMID: 33435490

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Project description:In a national sample of Medicare nursing home residents with dementia treated with bisphosphonates, 20% had bisphosphonates deprescribed. Residents with clinical characteristics representing decreased likelihood for long-term benefit were more likely to have bisphosphonates deprescribed. Future studies are needed to evaluate outcomes of deprescribing bisphosphonates in this population.IntroductionTo determine incidence of deprescribing bisphosphonates among nursing home (NH) residents with dementia and identify factors associated with deprescribing.Methods2015-2016 Medicare claims, Part D prescriptions, Minimum Data Set (MDS) 3.0, and Nursing Home Compare for non-skilled NH residents aged 65 + with dementia and prescriptions for oral bisphosphonates overlapping the first 14 days of the stay. Our primary definition for deprescribing was a 90-day gap in medication supply; we also explored the reliability of different deprescribing definitions (30-, 90-, 180-day gaps). We estimated associations of NH, provider, and resident characteristics with deprescribing bisphosphonates using competing risks regression models.ResultsMost NH residents with dementia treated with bisphosphonates (n = 5312) were ≥ 80 years old (72%), white (81%), and female (90%); about half were dependent for transfers (50%) or mobility (45%). Using a 90-day gap in supply, the 180-day cumulative incidence of deprescribing bisphosphonates was 14.8%. This increased to 32.1% using a 30-day gap and decreased to 11.7% using a 180-day gap. Factors associated with increased likelihood for bisphosphonate deprescribing were age ≥ 90 years, newly admitted (vs. prevalent stay), dependent for mobility, swallowing difficulty, > 1 hospitalization in the prior year, CCRC facility, and nurse practitioner primary provider (vs. physician). Cancer and western geographic region were associated with reduced likelihood for deprescribing.ConclusionIn a national sample of NH residents with dementia, bisphosphonate deprescribing was uncommon, and associated with clinical characteristics signifying poor prognosis and decreased likelihood for long-term benefit. Future studies should evaluate clinical outcomes of deprescribing bisphosphonates in this population.

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Dataset Information

The Use of MALDI-TOF Mass Spectrometry to Analyze Commensal Oral Yeasts in Nursing Home Residents.

Publications

The Use of MALDI-TOF Mass Spectrometry to Analyze Commensal Oral Yeasts in Nursing Home Residents.

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