title: Etiology of surgical site infections after primary total joint arthroplasties.
abstract: We sought to characterize the causative pathogens of surgical site infections (SSIs) following primary total joint arthroplasties and to evaluate trends in the microbial etiology. We analyzed the etiology of SSIs following 2,632 total hip arthroplasty and knee arthroplasty procedures performed at our institution from 2004 through 2010. We calculated the annual proportion of SSIs accounted for each of the most common organisms and evaluated trends using the χ(2) test for trend. SSIs were identified in 111 procedures (4.2%). The annual incidence of SSIs did not change significantly during the study period. Staphylococci were the most common cause of infection (59.6%) and most of infections were monomicrobial (82.8%). From 2004 to 2010, the annual proportion of infections due to gram-negative bacilli (GNB) increased from 21.4% to 66.7% (p = 0.085 for trend). This increase was accompanied by a decline in the proportion of SSIs from coagulase-negative staphylococci (p = 0.003). Additionally, we found an increase in the percentage of polymicrobial infections (from 7.1% in 2004 to 41.7% in 2010, p = 0.014). Multivariate analysis corroborated these trends. Our study reports an emergence of GNB as a cause of SSIs after primary total joint arthroplaties and an increase of polymicrobial infections.
authors.affiliation: Unit of Infectious Diseases, Department of Internal Medicine, Hospital de la Santa Creu i Sant Pau - Institut d'Investigació Biomèdica Sant Pau, Sant Antoni Maria Claret 167, 08025, Barcelona, Spain; Universitat Autònoma de Barcelona, Barcelona, Spain; Spanish Network for Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid.
authors.forename: Natividad
authors.initials: N
authors.lastname: Benito
authors.forename: María
authors.initials: M
authors.lastname: Franco
authors.forename: Pere
authors.initials: P
authors.lastname: Coll
authors.forename: María Luz
authors.initials: ML
authors.lastname: Gálvez
authors.forename: Marcos
authors.initials: M
authors.lastname: Jordán
authors.forename: Joaquín
authors.initials: J
authors.lastname: López-Contreras
authors.forename: Virginia
authors.initials: V
authors.lastname: Pomar
authors.forename: Joan Carles
authors.initials: JC
authors.lastname: Monllau
authors.forename: Beatriz
authors.initials: B
authors.lastname: Mirelis
authors.forename: Mercè
authors.initials: M
authors.lastname: Gurguí
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D008297:Male; D013030:Spain / Q000453:epidemiology; D013203:Staphylococcal Infections / Q000453:epidemiology; D013530:Surgical Wound Infection / Q000453:epidemiology / Q000209:etiology*
keywords: arthroplasty; microbial etiology; prosthetic joint infections; prosthetic joint replacement; surgical site infections