<p>Molecular typing revealed the emergence of <em>pvl</em>-positive sequence type 22 methicillin-susceptible <em>Staphylococcus aureus</em> in Urumqi, Northwestern China</p>

Abstract

Background Staphylococcus aureus is among the most common causes of health care- and community-associated infections worldwide. The distributions of different S. aureus clones change over time and also vary geographically. The purpose of this study was to determine the molecular type and antimicrobial resistance profiles of clinical S. aureus strains isolated in Urumqi, Northwestern China. Methods A total of 605 clinical S. aureus isolates were collected from Xinjiang Military General Hospital, in Urumqi. Protein A-encoding ( spa ) typing, multilocus sequence typing, staphylococcal chromosomal cassette mec typing, Panton-Valentine leucocidin ( pvl) gene detection, and antimicrobial resistance profiling were performed. Results Among these strains, 271 isolates (44.7%) were methicillin-resistant S. aureus (MRSA) and 334 (55.3%) were methicillin-susceptible S. aureus (MSSA). The MRSA strains consisted of 22 spa types and 14 sequence types (STs). ST239-MRSA-III-t030 (73.1%, 198/271) and ST59-MRSA-IV-t437 (11.8%, 32/271) were the most common, and ST22-MRSA-IV-t309 was the rarest (2.02%, 6/271). The MSSA strains consisted of 93 spa types and 29 STs. ST22, ST121, ST398, ST5, ST7, ST188, and ST15 were the main MSSA STs, and ST22-MSSA-t309 was most common (26.0%, 87/334). The pvl gene was present in 20.3% of all S.aureus strains, and 80.8% (88/99) of ST22-MSSA strains harbored the pvl gene. A total of 85.7% pvl -positive ST22-MSSA strains were spa t309 (85/99), and 87.5% of pvl -positive ST22-MSSA strains were from abscesses or wounds (skin and soft tissue infections). All ST239-MRSA strains were resistant to gentamicin (GEN), levofloxacin (LEV), ciprofloxacin (CIP), moxifloxacin (MXF), rifampicin (RIF), and tetracycline (TET). Among the ST59-MRSA strains, over 70.0% were resistant to erythromycin (ERY), clindamycin (CLI), and TET. ST22-MSSA remained susceptible to most antibiotics, but was resistant to PEN (97.0%), ERY (57.6%), and CLI (15.2%). Conclusion Our major results indicated that the antimicrobial resistance profiles and pvl genes of S. aureus isolates from Urumqi were closely associated with clonal lineage. ST239-MRSA-III-t030 and pvl -positive ST22-MSSA-t309 were the most common clones in this region of Northwestern China.

<p>Molecular Characteristics, Antimicrobial Resistance and Virulence Gene Profiles of <em>Staphylococcus aureus</em> Isolates from Wuhan, Central China</p>

“…Fu et al represented. Our finding differ from the recent studies that the most common SCCmec types were III in Guangdong and Xinjiang 27,28 and IV in Shanghai 29 and Trento. 30 In this study, AST also revealed that all or most of the isolates were susceptible to VAN, LZD, QUD, TST and NIT but were resistant to PEN, consistent with the results of most previous studies conducted in China and worldwide.…”

“…The most prevalent sequence types in both the total S. aureus and MRSA isolates were ST5 and ST239, and this finding differs from other reports. 27 Specifically, the predominant MRSA isolates were ST5 and ST398 in Shanghai in 2017, 18 ST239 and ST338 in Guangdong during 2010-2016, 28 ST239 and ST15 in Iran during 2015-16 35 and ST5 and ST8 in the United States during 2010-2011. 36 The predominant MSSA genotypes were ST188 and ST7, which was in accordance with the majority of previous studies.…”

Genetic analysis of methicillin‐susceptible Staphylococcus aureus clinical isolates: High prevalence of multidrug‐resistant ST239 with strong biofilm‐production ability

“…36,37 In Iran, the rate of fusidic acid resistance, during a 4-year period on 726 tested S aureus isolates, was found to be 3%. 38 According to the evidence low level of resistance to fusidic acid is China (34.4%), 6 Ireland (17%), 36 and Lebanon (12%) 4 A high prevalence of SEs genes was observed in the present study (52%). it was similar to 62.6% prevalence SEs genes in a study of Turkey.…”

“…A high prevalence of pvl among ST22 MSSA strains has been reported by Yuan et al6 (80.8%). Different virulence determinants in CC/ST22 have been reported by researchers 6,36. Contrary to earlier data that indicated HLMUPR in ST22 strains,28,36 our analysis confirmed a 23.8% prevalence of LLMUPR in Iran.…”

“…4,5 However, it is well established that several infections are caused by methicillin-susceptible S aureus (MSSA). 6,7 According to the evidence, variable rates of staphylococcal infections caused by MSSA have been reported in previously published data from Iran, ranged from 23.1% to 76.4%. 8 Nowadays, infection associated with MSSA is a major public health crisis representing a priority for healthcare settings.…”