Methicillin-resistant Staphylococcus aureus (MRSA) is a known burden on pediatric healthcare systems. A recent study sought to elucidate the genetic make-up and clinical characteristics of MRSA strains in children in Korea between 2016 and 2021, due to a dearth of data since the 2010s. Information was gathered retrospectively, through multilocus sequence typing (MLST) and Staphylococcal cassette chromosome mec (SCCmec) typing of MRSA isolate samples, and clinical data reviews. From a total of 172 instances of Staphylococcus aureus bacteremia, nearly 45% (77 incidences) demonstrated methicillin resistance. Interestingly, community-acquired infections represented a small subset, accounting for approximately 4% of the cases.
ST72 emerged as the most prevalent sequence type (ST) group at 67.6%, followed by ST5 (18.9%) and ST1 (5.4%). The ST5 group saw a significant reduction during 2019-2021, compared to 2016-2018. The ST72 group exhibited lower overall antimicrobial and multidrug resistance rates, in contrast to the ST5 and ST1 groups. The ST1 group was identified as a significant risk factor for all-cause mortality within 30 days.
The study showed that the ST72-MRSA strain continues to be the most frequent genotype found in Korean children, while the emergence of the ST1 group as a significant risk factor for mortality emphasizes the need for ongoing research on MRSA’s evolving epidemiology.
Staphylococcus aureus bacteremia (SAB) can lead to significant morbidity and mortality, despite appropriate antibiotic treatment. Variations occur in pediatric patient infection rates across various regions, with a higher prevalence among infants under one year of age. Understanding the changing molecular epidemiology of MRSA is crucial in curbing its transmission. Molecular typing methods can shed light on genetic backgrounds and the spread of MRSA isolates across different time periods and geographical regions.
Alarmingly, methicillin-resistant S. aureus (MRSA) has shown a considerable increase among pediatric patients admitted to tertiary hospitals in South Korea. Elevated prevalence rates have ranged from 65.2% to 76.1% between 2002 and 2016. Filling the gap in studies assessing the evolution of MRSA infections among Korean children since 2010 is essential, as the impact of particular MRSA genotypes on clinical outcomes remains largely unexplored.
Overall, these results underscore the need for continuous assessment of MRSA’s genomic landscape to devise effective strategies for prevention and treatment, in light of the changing epidemiology of this persistent bacterial pathogen.
Source: https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-023-08914-5