CASE REPORTSFirst report of an extended-spectrum β-lactamase-producing Raoultella ornithinolytica and a porin deficiency (OmpK35 absence) which was misidentified as Klebsiella oxytoca by an automated microbial identification systemZhang, Li-pinga; Li, Xiao-honga; Xue, Wen-chengb; Meng, Dong-yabAuthor Information aPostgraduate Training Base of General Hospital of Shenyang Military Command, Liaoning Medical University, Jinzhou bClinical Laboratory, General Hospital of Shenyang Military Command, Shenyang, China. Correspondence to Dong-ya Meng, General Hospital of Shenyang Military Command, Shenyang, Liaoning, China. E-mail: [email protected] Received 19 March, 2015 Revised 6 April, 2015 Accepted 6 April, 2015 Reviews in Medical Microbiology: January 2016 - Volume 27 - Issue 1 - p 33-35 doi: 10.1097/MRM.0000000000000054 Buy Metrics Abstract Raoultella ornithinolytica is an encapsulated Gram-negative aerobic bacillus belonging to the Enterobacteriaceae family. Originally it used to be a member of Klebsiella. However, in the year 2001, R. ornithinolytica was reclassified as a new genus type from the Klebsiella species along with two others, and this was based on new genetic approaches. Occurrence of Raoultella in human infections is rare, and its successful identification is confusing. We herein report a misidentification of R. ornithinolytica by the VITEK-2 Compact automatic microbial identification system (VITEK-2 AMS), but matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA analysis could correctly identify it. Copyright © Wolters Kluwer Health, Inc. All rights reserved.