Point-Counterpoint: What's in a Name? Clinical Microbiology Laboratories Should Use Nomenclature Based on Current Taxonomy

INTRODUCTION The mnemonic SPICE (Serratia, Pseudomonas, indole-positive Proteus, Citrobacter, and Enterobacter) has served as a reminder to consider when a Gram-negative organism may carry a chromosomal copy of bla(ampC), with the associated risk of developing resistance to first-, second-, and third-generation cephalosporins. However, in 2017, there was a well-founded proposal to rename Enterobacter aerogenes to Klebsiella aerogenes, based on whole-genome sequencing (WGS), and the SPICE mnemonic lost its relevance. With the increased use of WGS for taxonomy, it seems like bacteria and fungi are undergoing constant name changes. These changes create unique challenges for clinical microbiology laboratories, who would like to issue reports that are readily understood and that help clinicians determine empirical antibiotic therapy, interpret antimicrobial resistance, and understand clinical significance. In this Point-Counterpoint, Drs. Karen Carroll and Erik Munson discuss the pros of updating bacterial taxonomy and why clinical labs must continue to update reporting, while Drs. Susan Butler-Wu and Sheila Patrick argue for caution in adopting new names for microorganisms.

Automated summary

The mnemonic SPICE, used to remind about the presence of bla(ampC) gene, lost its relevance when Enterobacter aerogenes was renamed Klebsiella aerogenes based on whole-genome sequencing. With the increasing use of WGS for taxonomy, bacteria and fungi undergo constant name changes, posing challenges for clinical microbiology laboratories.