title: The Absence of Fever or Leukocytosis Does Not Exclude Infection Following Cranioplasty.
abstract: BACKGROUND
  Cranioplasty encompasses various cranial reconstruction techniques that are used following craniectomy due to stroke or trauma. Despite classical infectious signs, symptoms, and radiologic findings, however, the diagnosis of infection following cranioplasty can be elusive, with the potential to result in definitive treatment delay. We sought to determine if fever or leukocytosis at presentation were indicative of infection, as well as to identify any factors that may limit its applicability.
  
  
  METHODS
  Following institutional review board approval, a retrospective cohort of 239 patients who underwent cranioplasty following craniectomy for stroke or trauma was established from 2001-2011 at a single center (Massachusetts General Hospital). Analysis was then focused on those who developed a surgical site infection, as defined by either frank intra-operative purulence or positive intra-operative cultures, and subsequently underwent operative management.
  
  
  RESULTS
  In 27 total cases of surgical site infection, only two had a fever and four had leukocytosis at presentation. This yielded a false-negative rate for fever of 92.6% and for leukocytosis of 85.2%. In regard to infectious etiology, 22 (81.5%) cases generated positive intra-operative cultures, with Propionibacterium acnes being the most common organism isolated. Median interval to infection was 99 days from initial cranioplasty to time of infectious presentation, and average follow-up was 3.4 years.
  
  
  CONCLUSIONS
  The utilization of fever and elevated white blood cell count in the diagnosis of post-cranioplasty infection is associated with a high false-negative rate, making the absence of these features insufficient to exclude the diagnosis of infection.
authors.affiliation: 1Department of Neurosurgery,University of Calgary,Foothills Hospital,Calgary AB,Canada.
authors.forename: Fady
authors.initials: F
authors.lastname: Girgis
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Walcott
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Churl-Su
authors.initials: CS
authors.lastname: Kwon
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Sameer A
authors.initials: SA
authors.lastname: Sheth
authors.affiliation: 3Department of Neurosurgery and the Brown Institute for Brain Science,Brown University Alpert Medical School and Rhode Island Hospital,Providence,Rhode Island,USA.
authors.forename: Wael
authors.initials: W
authors.lastname: Asaad
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Brian V
authors.initials: BV
authors.lastname: Nahed
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Emad N
authors.initials: EN
authors.lastname: Eskandar
authors.affiliation: 2Department of Neurosurgery,Massachusetts General Hospital and Harvard Medical School,Boston,Massachusetts.
authors.forename: Jean-Valery
authors.initials: JV
authors.lastname: Coumans
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001930:Brain Injuries / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D056424:Decompressive Craniectomy / Q000009:adverse effects*; D005188:False Negative Reactions; D005260:Female; D005334:Fever / Q000209:etiology*; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000209:etiology / Q000382:microbiology; D006801:Humans; D007223:Infant; D007964:Leukocytosis / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011425:Propionibacterium acnes; D012189:Retrospective Studies; D020521:Stroke / Q000601:surgery; D013524:Surgical Flaps / Q000382:microbiology; D013530:Surgical Wound Infection / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D055815:Young Adult
keywords: complication; craniofacial surgery; cranioplasty; infections of the nervous system; trauma