Causes of Meningitis? [4]
How do we approach meningitis? [3]
How do we approach encephalitits? [4]
When would an LP be contraindicated? [6]
You don’t do it if there’s sign of a mass or swelling as the pressure [1] could cause herniation and death.
Causes of Encephalitis? [5]
What microorganisms cause infective meningitis? [2]
Neisseria Meningitidis (Meningococcus) Streptococcus Pneumoniae (Pneumococcus) Enteroviruses
How do we treat viral encephalitis?
Aciclovir based on clinical suspicion of Viral encephalitis.
Generally speaking, viral meningitis is self-limiting, with symptoms improving over the course of 7 - 14 days and complications are rare in immunocompetent patients.
How does HSV cause encephalitis? [2]
Initial infection resolves and becomes latent eg residing in trigeminal ganglion [1]
It reactivates later and can cause encephalitis - Type 1 HSV [1]
Name some enteroviruses [3] and how you spread and test for them in encephalitis? [2]
Polioviruses, coxsackie virus, echovirus
Faecal-oral spread
Do PCR of a stool sample if you suspect
Other than HSV and Enteroviruses what else causes infectious encephalitis? [1]
Arbovirus Encephalitides
Common in other parts of the world they are vector-transmitted (tick or mosquito) so a travel history is important
E.g. West Nile Virus (Location name viruses dont relate to current geographical distribution)
How does Meningitis Present? [5]
Classic triad of Fever, neck stiffness and altered mental status
Also:
- Short history of headache
- Meningism (Stiff neck, photophobia, N&V)
Cerebral dysfunction e.g. confusion is common and many have a lowered GCS
Cranial Nerve Palsies, Seizures and focal neuro deficits can occur
What presentation of meningitis is specific to which cause? [1]
Petechial Skin Rash
A hallmark of meningococcal meningitis (But can occur in viral)
How does Encephalitis Present? [6]
Flu-like Prodrome for 4-10 days
How is viral encephalitis different from bacterial meningitis? [2]
It has a slower onset and more prominent cerebral dysfunction…generally
Describe the types of auto-immune encephalitis? [2]
Anti-VGKC (Voltage Gated K Channel) antibodies:
- Seizures, Amnesia & Altered mental state
Anti-NMDA receptor antibodies:
Indications for an LP? [6]
To Diagnose:
To infuse drugs or contrast
Contraindications for a LP? [4]
What are the types of LP needle? [2]
- Atraumatic needles (Cause less spinal headaches but cost more)
What is used to anaesthetize for an LP? [2]
Topical anaesthetic to injection site such as EMLA
Lidocaine 1%
4mg per kg is maximum dose
OR lidocaine inserted intradermally, then carried through on needle
In what positions are an LP performed? [2]
Lateral (Decubitus) position:
- Lying on left side with maximally flexed spine (particularly at hips)
Sitting (Infants):
- Infants hands held between its flexed legs using one hand and the other hand flexes its head
What vertebral level is an LP performed? [2]
L3-4 in adults and L4-5 in infants
Procedure for an LP [8]
What do you do if theres no fluid? [3]
How is CSF pressure measured? [1]
With a Manometer in the lateral position only, once CSF starts to flow