CSF

Question 1

List causes of increased CSF pressure

Answer 1

• Changes in systemic blood pressure
• Space occupying mass (tumour, abscess)
• Secondary to trauma/hypoxic injury (haemorrhage, oedema)
• Hypercapnoea (increases cerebral blood flow therefore CSF pressure; may exacerbate cerebral oedema)
• Inflammation, especially of the arachnoid villi (reduced absorption of CSF)
• Venous compression increases blood volume in the cranial cavity and compression of the CSF space thus increasing CSF pressure (iatrogenic or post jugular thrombosis)

Question 2

List causes of xanthochromia

Answer 2

• Haemorrhage (usually previous)
• Inflammation
• Increased protein
• Direct bilirubin leakage
• Leakage of indirect bilirubin across a damaged BBB

Question 3

List common changes to CSF cytology and possible causes (broad categories rather than specific diseases)

Answer 3

• Increased large mononuclear cells: diseases of axonal degeneration, some encephalitis viruses (EEEV [also some neutropils], WEEV, WNV [primarily lymphocytes], Kunjin [also some neutrophils])
• Increased neutrophils: Encephalomyelitis, bacterial meningitis, parasitism, any disease with extensive inflammation
• Increased eosinophils: Severe parasitic disease.
• Increased lactate: EEEV, trauma, brain abscess (may be the only abnormality of CSF with a brain abscess)