Abstract
Previously there was scant data on the performance of laboratory testing to detect mecC-mediated beta-lactam resistance in Staphylococcus aureus Kriegeskorte and colleagues (J Clin Microbiol 56:e00826-17, 2018, https://doi.org/10.1128/JCM.00826-17) report the performance of various clinical tests for the detection of mecC-harboring methicillin-resistant S. aureus (MRSA), which failed to identify from 0 to 41% of tested mecC-harboring MRSA isolates. Changes in practice and new test development are necessary to address the challenge of mecC-harboring MRSA.