Prevalence and antimicrobial resistance of three clones (ST1223, ST2198, ST2250) of Staphylococcus argenteus clinical isolates in northern Japan

Meiji Soe Aung; Noriko Urushibara; Mitsuyo Kawaguchiya; Nobuhide Ohashi; Mina Hirose; Kenji Kudo; Masahiko Ito; Nobumichi Kobayashi

doi:10.1016/j.jgar.2024.11.004

Prevalence and antimicrobial resistance of three clones (ST1223, ST2198, ST2250) of Staphylococcus argenteus clinical isolates in northern Japan

J Glob Antimicrob Resist. 2024 Nov 25:S2213-7165(24)00445-4. doi: 10.1016/j.jgar.2024.11.004. Online ahead of print.

Authors

Meiji Soe Aung¹, Noriko Urushibara², Mitsuyo Kawaguchiya³, Nobuhide Ohashi⁴, Mina Hirose⁵, Kenji Kudo⁶, Masahiko Ito⁷, Nobumichi Kobayashi⁸

Affiliations

¹ Department of Hygiene, Sapporo Medical University School of Medicine, Hokkaido, Sapporo 060-8556, Japan. Electronic address: meijisoeaung@sapmed.ac.jp.
² Department of Hygiene, Sapporo Medical University School of Medicine, Hokkaido, Sapporo 060-8556, Japan. Electronic address: noriko-u@sapmed.ac.jp.
³ Department of Hygiene, Sapporo Medical University School of Medicine, Hokkaido, Sapporo 060-8556, Japan. Electronic address: kawaguchiya@sapmed.ac.jp.
⁴ Department of Hygiene, Sapporo Medical University School of Medicine, Hokkaido, Sapporo 060-8556, Japan. Electronic address: ohashin@sapmed.ac.jp.
⁵ Division of Pediatric Dentistry, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu 061-0293, Japan. Electronic address: minaniwa@hoku-iryo-u.ac.jp.
⁶ Sapporo Clinical Laboratory, Inc., Sapporo 060-0003, Japan. Electronic address: kudo-k@saturn.co.jp.
⁷ Sapporo Clinical Laboratory, Inc., Sapporo 060-0003, Japan. Electronic address: m-ito@saturin.co.jp.
⁸ Department of Hygiene, Sapporo Medical University School of Medicine, Hokkaido, Sapporo 060-8556, Japan. Electronic address: nkobayas@sapmed.ac.jp.

PMID: 39603343
DOI: 10.1016/j.jgar.2024.11.004

Abstract

Objectives: Staphylococcus argenteus, a newly described species of coagulase-positive Staphylococcus, was first identified in clinical isolates in northern Japan in 2019. The aim of the present study was to clarify the trends in the epidemiological features and antimicrobial resistance traits of S. argenteus in the recent years.

Methods: S. argenteus isolates from various clinical specimens were screened using MALDI-TOF and genotyped using the MLST scheme. Antimicrobial susceptibility was determined using broth microdilution test and resistance genes were detected by multiplex/uniplex PCR. Nucleotide sequences of hemolysin genes (hla, hlb, hld, and hlg) were determined and analyzed in some isolates.

Results: From August 2020 to December 2023, 210 isolates were identified as S. argenteus. The ratio of S. argenteus to S. aureus clinical isolates was 0.0045, showing a slightly decreasing trend compared to what was previously reported (2019.8-2020.7). Three genotypes, ST1223-coa-XV, ST2198-coa-XIV, and ST2250-coa-XId were identified, with ST2250 being dominant (49%) and exhibiting an increasing trend. S. argenteus isolates were almost susceptible to antimicrobials examined, while ST2198 isolates showed higher resistance rates to ampicillin, macrolides, and aminoglycosides than other clones, harboring blaZ, msrA, and aac(6')-Ie-aph(2")-Ia. Only eight isolates (4-ST2250, 3-ST1223, and 1-ST2198) did not show hemolysis on blood agar plates. These isolates had intact hemolysin genes and promoter regions; however, a novel deletion mutation in hlg-component A was detected in some hemolytic and non-hemolytic isolates.

Conclusions: The present study revealed the epidemiological trend of S. argenteus clones in northern Japan, along with the occurrence of non-hemolytic isolates with intact hemolysin genes.

Keywords: Japan; ST; Staphylococcus argenteus; hemolysin; prevalence.