Gram-stain-based antimicrobial selection reduces cost and overuse compared with Japanese guidelines.
BACKGROUND
The Gram stain has been used as an essential tool for antimicrobial stewardship in our hospital since the 1970s. The objective of this study was to clarify the difference in the targeted therapies selected based on the Gram stain and simulated empirical therapies based on the antimicrobial guidelines used in Japan.


METHODS
A referral-hospital-based prospective descriptive study was undertaken between May 2013 and April 2014 in Okinawa, Japan. All enrolled patients were adults who had been admitted to the Division of Infectious Diseases through the emergency room with suspected bacterial infection at one of three sites: respiratory system, urinary tract, or skin and soft tissues. The study outcomes were the types and effectiveness of the antibiotics initially selected, and their total costs.


RESULTS
Two hundred eight patients were enrolled in the study. The median age was 80 years. A significantly narrower spectrum of antibiotics was selected based on the Gram stain than was selected based on the Japanese guidelines. The treatments based on the Gram stain and on the guidelines were estimated to be equally highly effective. The total cost of antimicrobials after Gram-stain testing was less than half the cost after the guidelines were followed.


CONCLUSIONS
Compared with the Japanese guidelines, the Gram stain dramatically reduced the overuse of broad-spectrum antimicrobials without affecting the effectiveness of the treatment. Drug costs were reduced by half when the Gram stain was used. The Gram stain should be included in all antimicrobial stewardship programs.
Division of Infectious Diseases, Okinawa Chubu Hospital, 281 Miyazato, Uruma, Okinawa, 904-2293, Japan. taniyan260566@gmail.com.
Tomohiro
T
Taniguchi
Division of Infectious Diseases, Okinawa Chubu Hospital, 281 Miyazato, Uruma, Okinawa, 904-2293, Japan. tsuhasanefumi@gmail.com.
Sanefumi
S
Tsuha
Division of Infectious Diseases, Okinawa Chubu Hospital, 281 Miyazato, Uruma, Okinawa, 904-2293, Japan. s.shiiki@gmail.com.
Soichi
S
Shiiki
Division of Infectious Diseases, Okinawa Chubu Hospital, 281 Miyazato, Uruma, Okinawa, 904-2293, Japan. masashi.narita@gmail.com.
Masashi
M
Narita
D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000191:economics / Q000627:therapeutic use*; D000890:Anti-Infective Agents / Q000191:economics* / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D003365:Costs and Cost Analysis; D005260:Female; D005840:Gentian Violet / Q000191:economics; D017408:Guidelines as Topic; D006761:Hospitals; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D010619:Phenazines / Q000191:economics; D000067490:Prescription Drug Overuse / Q000191:economics; D011446:Prospective Studies; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; C035863:Gram's stain; D010619:Phenazines; D005840:Gentian Violet