title: Epidemiology of necrotizing infection caused by Staphylococcus aureus and Streptococcus pyogenes at an Iowa hospital.
abstract: The present study was performed to characterize the epidemiology of necrotizing soft tissue infection caused by Streptococcus pyogenes (n=14) and Staphylococcus aureus (n=14) isolates collected at the University of Iowa Hospitals and Clinics. An additional 9 S. pyogenes isolates were collected from patients being treated for mild respiratory infections and served as a comparison sample in the analysis. Patient data corresponding to the isolates (n=37) were also collected in order to identify risk factors or comorbid conditions possibly correlated with necrotizing fasciitis (NF). The prevalence of methicillin-resistant S. aureus among the study isolates was 35.7% (5/14), and the prevalence of the Panton-Valentine leukocidin (PVL) gene was 57% (8/14). The S. pyogenes NF (wound) isolates (n=14) belonged to 10 different emm types, none of which appeared to be associated with more severe disease when compared to the milder infection (throat) samples (n=9). Comorbid conditions such as diabetes and cardiovascular disease were significantly associated with NF. The results indicate that there may be a high prevalence of the PVL virulence factor in NF infections and that spa type t008 may be responsible for the increasing incidence of S. aureus NF infections in Iowa.
authors.affiliation: Department of Epidemiology, University of Iowa College of Public Health, Iowa City, IA, USA; Center for Emerging Infectious Diseases, University of Iowa College of Public Health, Iowa City, IA, USA.
authors.forename: Dipendra
authors.initials: D
authors.lastname: Thapaliya
authors.affiliation: Department of Epidemiology, University of Iowa College of Public Health, Iowa City, IA, USA; Center for Emerging Infectious Diseases, University of Iowa College of Public Health, Iowa City, IA, USA.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: O'Brien
authors.affiliation: Department of Epidemiology, University of Iowa College of Public Health, Iowa City, IA, USA; Center for Emerging Infectious Diseases, University of Iowa College of Public Health, Iowa City, IA, USA.
authors.forename: Shylo E
authors.initials: SE
authors.lastname: Wardyn
authors.affiliation: Department of Epidemiology, University of Iowa College of Public Health, Iowa City, IA, USA; Center for Emerging Infectious Diseases, University of Iowa College of Public Health, Iowa City, IA, USA. Electronic address: tsmit176@kent.edu.
authors.forename: Tara C
authors.initials: TC
authors.lastname: Smith
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D015897:Comorbidity; D005098:Exotoxins / Q000235:genetics; D019115:Fasciitis, Necrotizing / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D005260:Female; D005838:Genotype; D006785:Hospitals, University; D006801:Humans; D007484:Iowa / Q000453:epidemiology; D007956:Leukocidins / Q000235:genetics; D008297:Male; D016106:Methicillin Resistance; D008875:Middle Aged; D058889:Molecular Typing; D015995:Prevalence; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000473:pathology; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000473:pathology; D013297:Streptococcus pyogenes / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D002352:Carrier Proteins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; C014689:streptococcal M protein
keywords: Epidemiology; Infection; Necrotizing fasciitis; Staphylococcus aureus; Streptococcus pyogenes