Ventriculitis

OVERVIEW

Bacterial ventriculitis (BV) is inflammation of the ventricular drainage system, usually due to bacterial infection of the cerebrospinal fluid (CSF)

  • Ventriculitis can occur as a primary process, or as a complication of:
    • meningitis (30% of adult cases and up to 90% of neonatal cases)
    • cerebral abscess
    • intraventricular haemorrhage, or
    • iatrogenesis
  • Frequently associated with the presence of a CSF shunt, external ventricular drainage (EVD), or other intracranial device
  • most CSF shunt-related infections occur in the first month after insertion

EVD-RELATED VENTRICULITIS

Bacteria can access through skin site and connections between tubes

  • EVD-related infections rates range from <1% to 40% (9% in the UK according to Jamjoon et al, 2017)
  • mortality rates vary from 10% to 75%

Risk factors

  • length of time the EVD is in place (e.g >7 days)
  • management (e.g. frequency of manipulation of EVD, especially repeated sampling)
  • type of EVD
  • insertion technique
  • multiple catheter insertions or exchanges
  • underlying disease
  • neurosurgery
  • CSF leakage
  • previous infections

CAUSE

Usual organisms in EVD and CSF shunt infections:

  • Staphylococcus aureus
  • Coagulase negative Staphylococci (S. epidermidis)
  • GNBs (up to 25%; more common if VP shunt due to peritoneal contamination): Escherichia coli, Klebsiella species, Acinetobacter, and Pseudomonas species
  • consider fungi if immunosuppressed

CLINICAL FEATURES

Clinical features may be subtle in EVD-associated infections

  • headache
  • nausea and vomiting
  • fever
  • altered mental state
  • focal neurological deficits
  • secondary hydrocephalus/ raised ICP

INVESTIGATIONS

Blood tests

  • WBC, CRP and procalcitonin are not very helpful

CSF analysis

  • high WCC in the CSF (Normal RCC:WCC Ratio = 500:1 but this alone is of questionable reliability)
  • CSF protein may be normal or high
  • Reduction in CSF glucose may be a more sensitive indicator of infection
  • Elevated CSF lactate has not been proven of utility
  • Cell index (ratio of leukocytes to erythrocytes in CSF divided by leukocytes to erythrocytes in peripheral blood) may prove to be useful
    • usually about 1
    • tends to increase in ventriculitis, and fall with response to antibiotics
    • Beer et al (2009) used a 5-fold increase in Cell Index as indicative of ventriculitis (should be considered experimental)

CT/ MRI

  • Ventriculitis is detected best by T2 fluid-attenuated inversion recovery (FLAIR) images showing periventricular hyperintensity on ependymal enhancement and irregular intraventricular debris
  • CT may be non-specific

DIAGNOSTIC PITFALLS

In post-neurosurgical patients or patients with a ventriculostomy:

  • systemic inflammatory response and clinical signs may be absent or subtle
  • the CSF cell count may be elevated as a result of surgical manipulation and inflammation
  • no single parameter can reliably predict or exclude EVD-related infection
  • imaging should not delay treatment

MANAGEMENT

Treatment

  • Clinical suspicion of nosocomial ventriculitis mandates prompt initiation of empiric antibiotic therapy
  • Intravenous antibiotics (may vary according to local guidelines):
    • vancomycin 1.5 g (<12y: 30 mg/kg up to 1.5 g) Q12H (adjust for renal function)
    • PLUS EITHER:
      • ceftazidime 2 g (child: 50 mg/kg up to 2 g) IV Q8H, OR
      • meropenem 2 g (child: 40 mg/kg up to 2 g) Q8H
  • Intraventricular antibiotics
    • not used routinely
    • use preservative-free formulations
    • options (may vary according to local guidelines):
      • vancomycin 10 to 20 mg daily
      • gentamicin 4 to 8 mg daily, or
      • amikacin 30 mg daily
  • Removal +/- replacement of infected EVD if present
    • this may not be necessary unless there is inadequate response to antimicrobial therapy or the CSF is purulent
  • rationalise antibiotics according to sensitivity
  • antibiotic duration is usually 14 days after the last positive culture

Prevention in ICU

  • antibiotic- and silver-impregnated EVD catheters appear to reduce rates of BV but are not in universal use
  • remove EVD as early as possible (review indication daily)
  • access EVD in a protocolised meticulous sterile fashion
  • minimise the frequency of EVD manipulations
  • routine CSF cultures are not necessary but should be performed if fever (e.g. >38.5 C), peripheral leukocytosis, neurological deterioration, or a change in CSF appearance is noted

References and Links

Journal articles

  • Beer R, Pfausler B, Schmutzhard E, et al. Management of nosocomial external ventricular drain-related ventriculomeningitis. Neurocrit Care. 2009;10(3):363-7 [PMID 18982457]
  • Flint AC, Rao VA, Renda NC, et al. A simple protocol to prevent external ventricular drain infections. Neurosurgery. 2013 Jun;72(6):993-9; discussion 999 [PMID 23467249]
  • Jamjoom AAB, Joannides AJ, Poon MT, et al. Prospective, multicentre study of external ventricular drainage-related infections in the UK and Ireland. Journal of neurology, neurosurgery, and psychiatry. 2017 [PMID 29070645]

FOAM and web resources


CCC 700 6

Critical Care

Compendium

Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also the Innovation Lead for the Australian Centre for Health Innovation at Alfred Health and Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of two amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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