Antimicrobial therapy and outcome of methicillin-resistant Staphylococcus aureus endocarditis: A retrospective multicenter study in Japan.

Background: MRSA (methicillin-resistant Staphylococcus aureus)-infective endocarditis (IE) is associated with high morbidity and mortality. This study aimed to assess data from patients with MRSA-IE across multiple facilities in Japan, with a specific focus on antimicrobial therapy and prognosis.
Methods: This retrospective study enrolled patients with a confirmed diagnosis of IE attributed to MRSA, spanning the period from January 2015 to April 2019.
Results: Sixty-four patients from 19 centers were included, with a median age of 67 years. The overall mortality rate was 28.1% at 30 days, with an in-hospital mortality of 45.3%. The most frequently chosen initial anti-MRSA agents were glycopeptide in 67.2% of cases. Daptomycin and linezolid were selected as initial therapy in 23.4% and 17.2% of cases, respectively. Approximately 40% of all patients underwent medication changes due to difficulty in controlling infection or drug-related side effects. Significant prognostic factors by multivariable analysis were DIC for 30-day mortality and surgical treatment for 30-day and in-hospital mortality. For vancomycin as initial monotherapy, there was a trend toward a worse prognosis for 30-day and in-hospital mortality (OR, 6.29; 95%CI, 1.00-39.65; p = 0.050, OR, 3.61; 95%CI, 0.93-14.00; p = 0.064). Regarding the choice of initial antibiotic therapy, statistical analysis did not show significant differences in prognosis.
Conclusion: Glycopeptide and daptomycin were the preferred antibiotics for the initial therapy of MRSA-IE. Antimicrobial regimens were changed for various reasons. Prognosis was not significantly affected by choice of antibiotic therapy (glycopeptide, daptomycin, linezolid), but further studies are needed to determine which antimicrobials are optimal as first-line agents.
Competing Interests: Declaration of Competing interest Tokimatsu I. received scholarship donations from Shionogi Pharmaceuticals, Inc. and Daiichi Sankyo Co. Ltd. Ukimura A. received scholarship donations from Shionogi Pharmaceuticals, Inc. Hiroshige Mikamo received speaker honoraria from MSD K.K., FUJIFILM Toyama Chemical Co., Ltd., Miyarisan Pharmaceutical Co., Daiichi Sankyo Co., Ltd., Pfizer Japan Inc., Sanofi K.K., Sumitomo Pharma Co., Ltd., Kyorin Pharmaceutical Co., Ltd., Shionogi & Co., Ltd. Japan, Kowa Co. Ltd., Gilead Sciences K.K., GSK Group of Companies, Saraya Co. Ltd., Tsumura & Co. Japan, Nippon Becton Dickinson Company, Ltd., and FUKOKU Co., Ltd., grant supports from Asai Kasei Pharma Co., Shionogi & Co., Ltd., Sumitomo Pharma Co., Ltd., and FUKOKU Co., Ltd. Mitsutake K, Shinya N, Seki M, Ohara T, Uemura K, Fukunaga M, Sakai J, Nagao M, Sata M, Hamada Y, Kawasuji H, Yamamoto Y, Nakamatsu M, Koizumi Y, Aoyagi T, Sawai T, Tanaka T, Izumikawa K, Takayama Y, Nakamura K, Kanemitsu K, Nakajima K, and Akine D have no conflict of interest.
(Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)