Open AccessEvaluation of presumptive identification of Enterobacterales using CHROMagar Orientation medium and rapid biochemical tests
Author(s) -
Ohtaki Hirofumi,
Takahashi Akifumi,
Niwa Ayumi,
Yonetamari Jun,
Nakayama Asami,
Kuchibiro Tomokazu,
Ohta Hirotoshi,
Ito Hiroyasu,
Baba Hisashi,
Murakami Nobuo,
Ohkusu Kiyofumi
Publication year - 2020
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.23453
Subject(s) - identification (biology) , indole test , microbiology and biotechnology , orientation (vector space) , lysine decarboxylase , chemistry , chromatography , computational biology , biology , biochemistry , mathematics , enzyme , botany , geometry , putrescine , cadaverine
Background The use of matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry is gradually spreading among large‐scale laboratories; however, this method is impractical for small‐scale laboratories. In laboratories without access to these rapid identification methods, problems related to them remain unsolved. In this study, we aimed to develop a rapid and inexpensive method to presumptively identify Enterobacterales using CHROMagar Orientation medium. Methods The algorithm for presumptive identification of Enterobacteriaceae using CHROMagar Orientation medium was based on our previous studies. Modified property tests for indole, lysine decarboxylase, ornithine decarboxylase, and hydrogen sulfide were performed to evaluate the differentiation of the bacterial species. Results Using the type strains and clinical isolates, it was possible to conduct the property tests at a low cost, within 4 hours. The spot indole test was performed without any nonspecific reactions for the bacteria forming colored colonies. The presumptive identification of bacteria was thereby possible within 24 hours after specimen submission. Conclusion All these results suggest that the rapid presumptive identification of Enterobacterales is possible with this new identification method using CHROMagar Orientation medium. This is therefore a prompt and economical method that can be used in routine laboratory work.