title: Polymicrobial Staphylococcus aureus bacteremia: Frequency, distinguishing characteristics and outcome.
abstract: Staphylococcus aureus bacteremia (SAB) is usually monomicrobial (M-SAB). We reviewed SAB in adults (≥18years old) over a 13year-period and compared polymicrobial (P-SAB) and M-SAB. We encountered 93 P-SAB among 1537 SAB cases (6.1%). The source distribution was comparable; however, source-specified differences were apparent. P-SAB was noted in 12/58 (20.7%) necrotizing soft tissue infections/sacral decubiti and foot gangrene vs. 1/122 (0.8%) cellulitis/abscesses (P<0.001), in 7/64 (10.9%) femoral intravascular catheters (IVC) vs.16/376 (4.3%) IVC in other sites (P=0.03) and 15/134 (11.2%) healthcare-associated pneumonia (HAP) vs. 1/33 (3.0%) community-associated cases (P=0.1). Methicillin-resistance frequency was similar but community-associated SCCmec types (IV/V) were infrequent (17.9% vs. 34.2%; P=0.04). P-SAB was associated with higher mortality (50.5% vs. 24.2%; P<0.001) across nearly all sources. In summary, P-SAB is infrequent, usually encountered in necrotizing soft tissue infections/decubiti, femoral IVC and possibly HAP. The actual incidence of S. aureus in these infections should be defined.
authors: Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA. Electronic address: riad.khatib@stjohn.org.
authors: Riad
authors: R
authors: Khatib
authors: Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA.
authors: Mamta
authors: M
authors: Sharma
authors: Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA.
authors: Leonard B
authors: LB
authors: Johnson
authors: Department of Medical Education, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA.
authors: Kathleen
authors: K
authors: Riederer
authors: Department of Pathology, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA.
authors: Laurence
authors: L
authors: Briski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology; D060085:Coinfection / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
keywords: Bacteremia; Polymicrobial; Staphylococcus aureus