title: Cerebrospinal Fluid Infection Associated with Silver-Impregnated External Ventricular Drain Catheters.
abstract: OBJECTIVE
  Silver-impregnated external ventricular drains (EVDs) have reduced the number of cases of ventriculitis. Risk factors for developing ventriculitis associated with plain EVD catheters have been well documented and incorporated into clinical practice, but risk factors in association with silver EVDs are unknown. Therefore, we sought to determine the risk factors for developing ventriculitis in patients with a silver EVD.
  
  
  METHODS
  Prospectively collected data on consecutive patients undergoing insertion of a silver-impregnated EVD between October 2011 and September 2013 were analyzed. Cerebrospinal fluid (CSF) infection was defined as positive CSF microbiologic culture. Univariate and multivariate regression was performed to identify independent risk factors for CSF infection.
  
  
  RESULTS
  There were 362 EVDs placed in 263 patients (142 women; median age 52 years; interquartile range, 40-62 years). There were 15 infections (6.4 per 1000 days of EVD drainage) recorded. Gram-negative organisms (8 of 15) were most commonly observed, although Staphylococcus was the most common genus (7 of 15; 46%) identified. Univariate analysis indicated that patients requiring EVD replacement (P < 0.0001), patients requiring bilateral EVDs (P < 0.0001), and patients with a CSF leak (P < 0.0001) were at increased risk of infection. Only need for EVD replacement remained significant on multivariate analysis (P < 0.0001, odds ratio = 15.9, confidence interval = 4.5-55.9).
  
  
  CONCLUSIONS
  We identified an infection rate of 5.2% in this large contemporary series of patients undergoing silver EVD insertion according to a set protocol. These data suggest that targeting strategies to reduce Staphylococcus species is important, and increased vigilance for an increased incidence of gram-negative organisms is needed. Decreasing the need for EVD replacement is important in reducing infection rates further.
authors.affiliation: Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, United Kingdom; Institute of Cardiovascular Sciences, The University of Manchester, Manchester, United Kingdom.
authors.forename: Ross
authors.initials: R
authors.lastname: Atkinson
authors.affiliation: Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Lubna
authors.initials: L
authors.lastname: Fikrey
authors.affiliation: Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, United Kingdom.
authors.forename: Anna
authors.initials: A
authors.lastname: Jones
authors.affiliation: Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, United Kingdom. Electronic address: cjpringle@doctors.org.uk.
authors.forename: Catherine
authors.initials: C
authors.lastname: Pringle
authors.affiliation: Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, United Kingdom; Institute of Cardiovascular Sciences, The University of Manchester, Manchester, United Kingdom.
authors.forename: Hiren C
authors.initials: HC
authors.lastname: Patel
mesh_terms: D000328:Adult; D055499:Catheter-Related Infections / Q000453:epidemiology*; D020806:Central Nervous System Bacterial Infections / Q000134:cerebrospinal fluid* / Q000453:epidemiology* / Q000209:etiology; D002555:Cerebrospinal Fluid / Q000382:microbiology; D002559:Cerebrospinal Fluid Rhinorrhea / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000209:etiology; D002557:Cerebrospinal Fluid Shunts / Q000009:adverse effects*; D004322:Drainage / Q000009:adverse effects* / Q000295:instrumentation*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D012834:Silver; D013203:Staphylococcal Infections / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000209:etiology; D013210:Staphylococcus
chemical_list: D012834:Silver
keywords: CSF infections; Catheter-related infection; EVD; Silver EVDs