Ventriculitis¶

Pathophysiology¶

• Caused by bacterial, viral, or fungal infections
• Common pathogens:
  • Gram-negative bacteria (e.g., E. coli, Klebsiella)
  • Staphylococcus species
  • Streptococcus species
• Inflammation leads to:
  • Ependymal cell damage
  • Increased permeability of blood-brain barrier
  • Accumulation of inflammatory cells and debris in ventricles
• Can result in hydrocephalus and increased intracranial pressure

Demographics¶

• Risk factors:
  • Neurosurgical procedures (e.g., ventriculostomy, shunt placement)
  • Intraventricular haemorrhage
  • Prematurity in neonates
  • Immunocompromised status
• Incidence:
  • 0.8-5.5% following external ventricular drain placement
  • Higher in neonates with intraventricular haemorrhage

Diagnosis¶

• Clinical presentation:
  • Fever
  • Altered mental status
  • Headache
  • Neck stiffness
  • Seizures
• Laboratory findings:
  • Elevated CSF white blood cell count
  • Decreased CSF glucose
  • Elevated CSF protein
• Microbiological culture of CSF
• Molecular techniques (e.g., PCR) for pathogen identification

Imaging¶

• CT findings:
  • Ventricular dilatation
  • Periventricular hypodensity
  • Intraventricular debris or air bubbles
• MRI findings:
  • T1-weighted images:
  • Ependymal enhancement with gadolinium
  • Intraventricular debris (hyperintense)
  • T2-weighted images:
  • Periventricular hyperintensity (oedema)
  • Intraventricular debris (hypointense)
  • FLAIR:
  • Hyperintense signal in ventricles
  • Periventricular oedema
• Advanced techniques:
  • Diffusion-weighted imaging: Restricted diffusion in purulent material
  • MR spectroscopy: Elevated lactate and lipid peaks

Treatment¶

• Antibiotics, CSF drainage and removal of infected devices. Ependymal enhancement with intraventricular debris/fluid levels and restricted diffusion (pus) is the imaging signature

Differential diagnosis¶