Neuro Infections of CNS lecture notes

Question 1

What is meningitis?

Answer 1

Inflammation of the meninges (in to out is PAD - pia, arachnoid dura mater)

Question 2

What are non-infective causes of meningitis?

Answer 2

Paraneoplastic (factors released by tumour affecting the brain)
Drug side effects
Autoimmune (eg SLE, vasculitis)

Question 3

How does infection get into the CNS?

Answer 3

Bacteraemia
Infection elsewhere locally eg. sinus, ear
Iatrogenic (eg neurosurgery)

Question 4

Bacteria enters CSF via e____ (intracellularly) or paracellularly

Answer 4

endothelial

Question 5

What symptoms do you get with meningitis

Answer 5

Neck stiffness
Fever
Headache
Photophobia
Vomiting

Question 6

On arrival to hospital what are the immediate management for bacterial meningitis?

Answer 6

Assess GCS
Blood cultures
Broad spec antibiotics

Question 7

What is a good first line broad antibiotic for meningitis?

Answer 7

Ceftriaxone or cefotaxime

Question 8

Amoxicillin is also given for listeria which may have occurred if the patient has…

Answer 8

Travelled

Question 9

What is a definitive investigation to diagnose meningitis?

Answer 9

Lumbar puncture

Microscopy, gram stain, culture, protein, glucose, viral PCR
Consider AFB (acid-fast bacilli) if suspect TB from history

Question 10

What are some lumbar puncture contraindications?

Answer 10

Abnormal clotting (don’t want to make patient bleed)

Infection at the lumbar puncture site

Raised intracranial pressure (risk of coning = herniation down into spinal cord)

Petechial rash (may indicate sepsis and coagulation issue from DIC)

Question 11

When to do a CT head before a lumbar puncture?

Answer 11

Papilledema (indicates raised ICP)
GCS 12 or lower
Continuous or uncontrolled seizures
Focal neurological signs

Question 12

Describe properties of Neisseria meningitidis

Answer 12

Gram negative diplococci

Question 13

What can cause chronic CNS infections?

Answer 13

TB
Syphilis
Cryptococcal (fungi)

Question 14

What are viral causes of meningitis?

Answer 14

Herpes simplex virus (HSV)
Varicella zoster virus (VZV)
Enterovirus

Question 15

What age most commonly get infected by group B strep?

Answer 15

Neonates

Question 16

How to differentiate subarachnoid haemorrhage from meningitis

Answer 16

Subarachnoid haemorrhage normally has “thunderclap” onset, may have had trauma

Question 17

What are differentials to meningitis?

Answer 17

Subarachnoid haemorrhage
Migraine
Flue and other viral illness
Sinusitis
Brain abscess
Malaria

Question 18

Is meningitis notifiable?

Answer 18

Yes
Identify “close contacts”

Question 19

What is encephalitis?

Answer 19

Inflammation of the brain

Question 20

What symptoms are different for encephalitis to meningitis?

Answer 20

Confusion
Behaviour change
Seizures

Question 21

What are causes of encephalitis?

Answer 21

Herpes simplex virus
Varicella zoster

Measles
mumps
rubella
coxsackie
tick-borne
Rabies
West Nile…

Autoimmune, paraneoplastic

Tetanus

Question 22

Encephalitis normally has a preceding flu-like illness followed by…

Answer 22

Altered GCS
Fever
Seizure
Memory loss

Question 23

Tetanus bacteria can produce a toxin called tetanospasmin which can travel along axons and interfere with n______ release increasing neuron firing

Answer 23

neurotransmitter

Question 24

What are symptoms of tetanus?

Answer 24

Spasms locally
Locked jaw (severe)
Back spasm

Question 25

How to manage tetanus

Answer 25

Muscle relaxants
Paracetamol
Immunoglobulin
Antibiotic

Question 26

What is rabies?

Answer 26

Viral infection that enters via skin with saliva of rabid animal
Travels retrogradely along nerves.
has a 100% mortality rate without vaccination
Vaccination gives time to access immunoglobulin

Question 27

What are the 2 types of rabies

Answer 27

Furious and paralytic

Question 28

Cryptococcal meningitis is mainly seen in what population?

Answer 28

HIV