Emergence of Community-Genotype Methicillin-ResistantStaphylococcus aureusin Korean Hospitals: Clinical Characteristics of Nosocomial Infections by Community-Genotype Strain

Abstract

BackgroundAs community-genotype methicillin-resistant Staphylococcus aureus (MRSA) strains spread into hospitals, the genotypes of the MRSA strains causing hospital-acquired (HA) infections have become more diverse. We describe clinical characteristics of nosocomial MRSA infections by a community-genotype of sequence type (ST) 72.Materials and MethodsA case-control study was designed among patients with HA-MRSA infections. Forty patients with infections caused by ST72-MRSA SCCmec type IV were selected as cases. Cases were matched to the controls with 106 patients infected with ST5/ST239 MRSA, which are representative hospital genotypes in Korea.ResultsPatients infected with ST72 isolates were younger than those with ST5/ST239 isolates. Female gender predominated among ST72 MRSA group compared to ST5/ST239 MRSA group. Solid tumor was a more frequent underlying disease in MRSA infections by ST72 isolates, whereas underlying renal, lung, heart, and neurologic diseases were more frequently found in those by ST5/ST239 isolates. The most common type of infection was pneumonia in both ST72 and ST5/ST239 groups (45.0% vs. 51.9%), followed by skin and soft tissue infection (SSTI). Female gender and underlying solid tumor were identified to be independent predictors for MRSA infections by ST72 isolates. All-cause mortality rates (20.0% vs. 30.2%) were not different between the groups.ConclusionA community-genotype MRSA, ST72 isolate has emerged as a nosocomial pathogen presenting as hospital-acquired pneumonia and SSTI. Although differences in underlying disorders were found, the distribution of infection type and mortality rate did not differ between the groups.

Prevalence and Characteristics of Antimicrobial-Resistant Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus from Retail Meat in Korea

“…Since then, studies worldwide have documented the presence of MRSA in various food-producing animals and people in frequent contact with these animals ( Fitzgerald, 2012 ). In Korea, MRSA has been reported in nonclinical sources, including pigs ( Lim et al, 2012 ), milk ( Song et al, 2016 ), and dogs ( Kwon et al, 2006 ), as well as clinical isolates ( Joo et al, 2017 ; Kim et al, 2018 ; Moon et al, 2015 ). However, little is known about the presence of antimicrobial-resistant S. aureus and MRSA from retail meats in Korea.…”

Characterization of Infections with Vancomycin-Intermediate Staphylococcus aureus (VISA) and Staphylococcus aureus with Reduced Vancomycin Susceptibility in South Korea

“…A recent retrospective study demonstrated that the molecular epidemiology of S. aureus is changing in Korea: a community-genotype MRSA strain, ST72, has emerged as a nosocomial pathogen 34 . Typically, SCC mec type II and ST5 strains are correlated with hospital-associated MRSA whereas SCC mec type IV and ST72 are correlated with community-acquired MRSA 35,36 .…”

Genome-Wide Analysis of Staphylococcus aureus Sequence Type 72 Isolates Provides Insights Into Resistance Against Antimicrobial Agents and Virulence Potential

“…Community-associated methicillin-resistant or -sensitive S. aureus (CA-MRSA/MSSA) sequence type 72 (ST72) is a prevalent isolate in South Korea ( Joo et al, 2012 ). The long-standing perception that ST72 isolates have low levels of virulence and resistance has recently been challenged by the finding that these isolates are resistant to desiccation and can adapt to hypotonic solutions, both of which can promote their survival in a hospital setting ( Joo et al, 2017 ). CA-MRSA ST72 has evolved resistance to multiple antimicrobial agents through various mechanism ( Stapleton and Taylor, 2002 ; Sutcliffe and Leclercq, 2002 ; Blair et al, 2015 ; Munita and Arias, 2016 ; Varona-Barquin et al, 2017 ; Moreno-Flores et al, 2018 ).…”