title: Blood cultures in the evaluation of uncomplicated cellulitis.
abstract: OBJECTIVE
  The frequency of bacteremia and the array of microorganisms involved in cellulitis vary greatly among studies. Although current guidelines do not recommend routine blood culture in uncomplicated cellulitis, their implementation in clinical practice remains challenging. We therefore aimed to assess the frequency, determinants and microbiology of bacteremia in hospitalized patients with uncomplicated cellulitis.
  
  
  METHODS
  We retrospectively reviewed the medical records of all adult patients admitted at a primary-care hospital with a diagnosis of community-acquired uncomplicated cellulitis during a 4-year period. We looked at the factors associated with blood cultures sampling and at the incidence, determinants and microbiology of bacteremia in this population.
  
  
  RESULTS
  Among the 476 patients hospitalized with a diagnosis of cellulitis, 250 (52.5%) had blood cultures. Fever, high C-reactive protein and lymphatic insufficiency were significantly associated with the sampling of blood cultures. Twelve (4.8%) patients had bacteremia. Alcoholism and duration of hospitalization were associated with bacteremia in multivariate analysis. Among the 12 patients with bacteremia, 9 had Streptococcus sp. and 3 had Staphylococcus aureus infection.
  
  
  CONCLUSIONS
  In our study population with uncomplicated cellulitis, representative of unselected population admitted at primary-care hospitals, bacteremia was uncommon and not associated with discriminant patient characteristics, except for alcohol abuse. Episodes of bacteremia were exclusively due to gram-positive cocci susceptible to co-amoxicilin, a common first-line empirical therapy. In accordance with existing guidelines, we do not recommend to collect blood for cultures in uncomplicated cellulitis. Clinicians' awareness of guidelines and of the poor yield of blood cultures could reduce useless investigation.
authors.affiliation: Department of Internal Medicine, Fribourg Hospital, Switzerland. Electronic address: sophie_bauer@bluewin.ch.
authors.forename: Sophie
authors.initials: S
authors.lastname: Bauer
authors.affiliation: Department of Internal Medicine, Fribourg Hospital, Switzerland; Department of General Internal Medicine, Bern University Hospital, Bern, Switzerland.
authors.forename: Carole E
authors.initials: CE
authors.lastname: Aubert
authors.affiliation: Department of Information Technology, Fribourg Hospital, Switzerland.
authors.forename: Mischa
authors.initials: M
authors.lastname: Richli
authors.affiliation: Department of Internal Medicine, Fribourg Hospital, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Chuard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000437:Alcoholism / Q000453:epidemiology; D016470:Bacteremia / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism; D000071997:Blood Culture / Q000706:statistics & numerical data*; D002097:C-Reactive Protein / Q000378:metabolism; D002481:Cellulitis / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism; D005260:Female; D005334:Fever / Q000453:epidemiology; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007902:Length of Stay / Q000706:statistics & numerical data; D008206:Lymphatic Diseases / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000453:epidemiology*; D013211:Staphylococcus aureus; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology*; D013557:Switzerland / Q000453:epidemiology; D019564:Unnecessary Procedures; D055815:Young Adult
chemical_list: D002097:C-Reactive Protein
keywords: Bacteremia; Blood cultures; Cellulitis; Erysipelas; Microbiology; Skin infection