CNS infections Flashcards
features of meningitis
Fever Altered mental state Headache Nausea Neck stiffness Nuchal rigidity Focal neurological deficit (eye signs, limb parasthesia) Meningococcal rash
bacterial causes of meningitis
streptococcus pneumoniaae
- Neisseria meningitidis
- Haemophilus influenza
- Listeria monocytogenes (immunosuppressed, pregnancy, age extremes)
Viral causes of meningitis
Enteroviruses HSV VZV EBV Mumps
bedside Investigations for meningnitis and viral encephalitis
ABCDE
-FBC, UE, LFT, CRP, clotting, blood cultures, meningococcal/pneumococcal PCR, lactate, glucose, throat swab, stool sample, HIV
Imaging for meningitis and viral encephalitis
CT, MRI
Invasive investigations for meningitis and viral encephalitis
Lumbar puncture to check:
-opening pressure, protein, cell count, MCS, glucose and serum glucose, viral PCR, meaning/pneumococcal PCR
When not to do a lumbar puncture
-Signs of raised ICP
Seizures
Papilloedema
Focal neurological signs
GCS>12
-Signs of meningococcal septicaemia (systemically unwell and rash)
-Evidence of potential bleeding risk (platelets <50, INR >1.2)
-History of clotting disorder (haemophilia)
What is opening pressure, WCC, cell differential, protein and CSF glucose like in bacterial meningitis
OP- high WCC- high Cell differential- polymorph Protein- high CSF glucose- very low
what opening pressure, WCC, cell differential, protein and CSF glucose like in viral meningitis
OP- normal WCC- high Cell differntial - lymphocytes Protein-high CSG glucose - normal
what opening pressure, WCC, cell differential, protein and CSF glucose like in fungal meningitis
OP- variable WCC- variable Cell differntial - lymphocytes Protein- high CSG glucose - low
what opening pressure, WCC, cell differential, protein and CSF glucose like in TB meningitis
OP- variable WCC- variable Cell differntial - lymphocytes Protein- high CSG glucose - low
viral encephalitis symptoms
Most important:
Fever
Seizure
Change in mental state
Headache
Focal neurological deficit
cerebral abscess features
-How is it spread
Headache, fever, altered mental status, focal signs and seizures
- CSF doesn’t;t have many findings
- Seen via imaging
- Typically spread from sinuses or via blood
how is being immunocpmpromised relevant in treating conditions
They are more susceptible to less common organisms
e.g. toxoplasmosis, cryptococcus, TB, aspergillus
