title: Microbiology of surgical site infections in patients with cancer: A 7-year review.
abstract: BACKGROUND
  Health care-associated infections (HAIs) have arisen as major sources of multidrug-resistant bacteria. Surgical site infections (SSIs) are the most frequent HAIs in many countries, with high antimicrobial-resistant prevalence.
  
  
  METHODS
  A 7-year retrospective review (2008-2014) of microbiologic data within a prospective surveillance program on patients with SSI at a cancer hospital in Mexico.
  
  
  RESULTS
  There were 23,421 surgeries performed during the study period. The SSI rate was 7.9%. Gram-negative bacilli (GNB) were found in 56.5% of samples. Escherichia coli was the most frequent microorganism (27.5%), followed by Staphylococcus aureus (16.3%). SSI caused by S aureus showed a decreasing trend (P = .04). Extended-spectrum β-lactamase (ESBL)-producing E coli increased from 39.5% in 2008 to 72.5% in 2014 (P < .001). Fluoroquinolone resistance also increased in all members of the Enterobacteriaceae. Methicillin-resistant S aureus (MRSA) was isolated in 32% of cases with no significant increase (P value is not significant).
  
  
  CONCLUSIONS
  GNB caused most SSIs, with an increase of ESBL E coli strains. In breast and thoracic surgery, S aureus remained the most frequent isolate. MRSA remained stable throughout the study period. We observed a decreasing trend in S aureus. These findings show the differences in the microbiology of SSIs in a middle-income country and the increasing trend of ESBL enterobacteria and other multidrug-resistant organisms, such as Enterococcus faecium.
authors.affiliation: Department of Infectious Diseases, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Hernaiz-Leonardo
authors.affiliation: Department of Infectious Diseases, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Maria Fernanda
authors.initials: MF
authors.lastname: Golzarri
authors.affiliation: Department of Infectious Diseases, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Patricia
authors.initials: P
authors.lastname: Cornejo-Juárez
authors.affiliation: Department of Infectious Diseases, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Patricia
authors.initials: P
authors.lastname: Volkow
authors.affiliation: Microbiology Laboratory, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Velázquez
authors.affiliation: Programa de estudios combinados en medicina, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Ostrosky-Frid
authors.affiliation: Department of Infectious Diseases, Instituto Nacional de Cancerología, Mexico City, Mexico. Electronic address: diana_vilar@yahoo.com.mx.
authors.forename: Diana
authors.initials: D
authors.lastname: Vilar-Compte
mesh_terms: D000328:Adult; D000368:Aged; D001419:Bacteria / Q000145:classification* / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D009369:Neoplasms / Q000601:surgery*; D015995:Prevalence; D012189:Retrospective Studies; D013530:Surgical Wound Infection / Q000453:epidemiology / Q000382:microbiology*
keywords: Microbiology; Multidrug-resistant bacteria; Neoplasms; Surgical site infection