Received: 14 October 2020
Accepted: 30 November 2020
First Online: 7 December 2020
Ethics approval and consent to participate
: Because Gram-stain-based antimicrobial therapy is the standard practice at Okinawa Chubu Hospital, and because this was a retrospective observational study, written informed patient consent was deemed unnecessary. The study proposal was approved by the Institutional Review Board of Okinawa Chubu Hospital (No. 49, 2014).
: Not applicable.
: The authors declare that they have no competing interests.