Clinical and molecular epidemiology of invasive Staphylococcus aureus infection in Utah children; continued dominance of MSSA over MRSA

Abstract

Background Invasive Staphylococcus aureus infections are a common cause of morbidity and mortality in children. In the early 2000's the proportion of infections due the methicillin-resistant S. aureus (MRSA) increased rapidly. We described the clinical and molecular epidemiology of invasive S. aureus disease in a pediatric population. Methods We prospectively identified children in Utah with invasive S. aureus infections. Medical records were reviewed to determine diagnosis and clinical characteristics. Isolates were genotyped using multi-locus sequence typing. The presence of genes encoding the Panton-Valentine leukocidin (PVL) was determined using polymerase chain reaction. Results Over a 4-year period between January 2009 and December 2012, we identified 357 children, hospitalized at Primary Children's Hospital, with invasive S. aureus infections and isolates available for the study. Methicillin-susceptible S. aureus (MSSA) caused 79% of disease, while MRSA caused only 21% of disease. Mortality associated with invasive S. aureus infection was 3.6%. The most common diagnoses were osteoarticular infections (38%) followed by central line associated blood stream infections (19%) and pneumonia (12%). We identified 41 multi-locus sequence types. The majority of isolates belonged to 6

Utility of Methicillin-Resistant Staphylococcus aureus Nares Screening in Hospitalized Children with Acute Infectious Disease Syndromes

“…While it has been shown that a large proportion of children are intermittently colonized with S. aureus, our study, like others, has found only a minority (7.4%) of children being colonized with MRSA [11][12][13]. Moreover, of the children in this study with documented growth of S. aureus in clinical culture, MSSA dominated over MRSA (MSSA, 23/30 (76.7%) vs. MRSA, 7/30 (23.3%)), as has also been shown in a recent study of children with invasive S. aureus infections in which MRSA accounted for only one in five of the infections [14]. Together those findings are suggestive of a low background prevalence of MRSA infection at our institution and hence may support the utility of the MNS in a clinical context.…”

Bioguided Isolation of Active Compounds from Rhamnus alaternus against Methicillin-Resistant Staphylococcus aureus (MRSA) and Panton-Valentine Leucocidin Positive Strains (MSSA-PVL)

“…They have noted a dominance of MSSA isolates (N = 132) over MRSA (N = 39), but there was no significant difference in antibiotic use rate, cure rate, and median number of aspirations performed to cure [ 56 ]. However, in a prospective study, it was noted that MSSA caused 79% of infections, while MRSA caused only 21% concluding that during the study period MSSA was the main cause of invasive S. aureus infections but the classical virulence toxin PVL was rare in these isolates [ 57 ]. Furthermore, Sapri et al have demonstrated that the most virulent genes, such as PVL, were more frequently found in MSSA than in MRSA.…”

A quantitative assessment of Staphylococcus aureus community carriage in Yuma, Arizona

“…Staphylococcus aureus is a human commensal and opportunistic pathogen that causes skin and soft-tissue infection, bone and joint infection, bacterial endocarditis, and bacteremia (Williams 1963; Tong et al 2015). Methicillin-resistant S. aureus (MRSA) has received particular attention due to treatment challenges surrounding antibiotic resistance and its high burden on the health-care system, though recent data suggest that invasive methicillin-susceptible S. aureus (MSSA) cases significantly outnumber MRSA cases (Centers for Disease Control and Prevention 2020; Koeck et al 2019; Jackson et al 2020; Crandall et al 2020). Increased effort to control life-threatening S. aureus infections in hospitals has resulted in a steady decline in cases over the past 15 years (Kourtis et al 2019).…”