Infections of CNS

Question 1

what is meningitis?

Answer 1

inflammation of the meninges

meninges= lining of brain + spinal cord

Question 2

what is more serious- bacterial or viral meningitis?

Answer 2

usually bacterial

Question 3

most common cause of bacterial meningitis?

Answer 3

NEISSERIA MENINGITIS= most common

Question 4

what type of bacteria is neisseria meningitis?

Answer 4

gram negative diplococcus

Question 5

Most common cause of bacterial meningitis- neonates?

Answer 5

-Listeria monocytogenes
-Group B strep
-E.Coli

LEG- neonates do not use their legs

Question 6

Most common cause of bacterial meningitis- infants + children ?

Answer 6

H. influenza

Question 7

Most common cause of bacterial meningitis- 10-21 years?

Answer 7

neisseria meningitis

Question 8

Most common cause of bacterial meningitis- >21?

Answer 8

Strep pneuomoniae
Neisseria meningitis

More exposed to pneumonia
Neisseria meningitis= most common and >21s are probs going to hospital if something is wrong

Question 9

Most common cause of bacterial meningitis- >65?

Answer 9

Strep pneumonia
Listeria monocytogenes

Lost at this age
They all die of pneumonia

Question 10

presentation meningitis?

Answer 10

Triad of:
-headache
-neck stiffness
-fever

photophobia + vomiting are often present

Question 11

how may meningococcal septicaemia present?

Answer 11

-a non-blanching rash
-Red or purple
-Initially small spots in groups anywhere on body, become blotchy, little bruises

Question 12

invstigations bacterial meningitis?

Answer 12

Lumbar puncture

Question 13

what is seen on LP in bacterial meningitis?
-CSF
-Protein
-Glucose
-WCC

Answer 13

Within the hour and treatment commended immediately after
-CSF cloudy
-Protein high (>220)
-Glucose low (<34)
-WCC high (neutrophilia)
-Culture: bacteria

Question 14

Treatment- Bacterial meningitis in adults?

Answer 14

-Dexamethasone ( give steroids with or before Abs for 4 days)
-Ceftriaxone (IV)
Penicillin allergy= chloramphenicol

Add Amoxicillin IV 2g 4 hourly if:
Penicillin allergy= co-trimoxazole
≥ 60 years
Immunocompromised
Neonatal
Alcoholic
DM

if in community e,.g. GP= benzylpenicillin

Question 15

Treatment- bacterial meningitis in children?

Answer 15

<3 months Cefotaxime + Amoxicillin

3 months 1st dose Cefotaxime followed 6 hours later with once daily Ceftriaxone
+/- Dexamethasone IV starting before or with first dose of antibiotic
Chloramphenicol if penicillin allergic

Question 16

who gets additional amoxicillin (or co trimoxazole if penicillin allergic) with bacterial meningitis?

Answer 16

≥ 60 years
Immunocompromised
Neonatal
Alcoholic
DM

Question 17

LP- viral meningitis?
opening pressure
WBC
gram stain
protein
CSF appearance

Answer 17

Opening pressure= normal/elevated
Cells= lymphocytes (WBC elevates)
Gram stain= -ve
Bacterial antigen detection= -ve
Protein= normal/ slightly raised
CSF= clear

Question 18

treatment- viral meningitis?

Answer 18

supportive and self limiting (4-10 days)

Question 19

LP aseptic meningitis?

Answer 19

low WBC
minimal protein elevation
Normal glucose

Question 20

infectious causes of aseptic meningitis?

Answer 20

HSV1/2
Lyme’s
Enterovirus
Malaria
Mumps
Measles

Question 21

non infectious causes of aseptic meningitis?

Answer 21

Carcinomatous
Sarcoidosis
Vasculitis
Drugs

Question 22

what suggests that meningitis is more likely to be viral?

Answer 22

Recent flu-like illness.

Lack of vaccination.

Travel hx, insect bites etc.

Typically more focal neuro. changes than
bacterial (seizures, behavioural changes etc).

Question 23

common causes of viral meningitis?

Answer 23

-enteroviruses (echovirus, Coxsackievirus) MOST COMMON
-Mumps
-HSV and herpes zoster virus
-HIV
-Measles
-Influenza
arboviruses

Question 24

LP for TB meninigitis?
Opening pressure
WBC
Gram stain
Protein
Blood glucose

Answer 24

opening pressure= elevates
WBC= lymphocytes
Gram stain= +ve or -ve
Protein high/very high
<60% blood glucose

Question 25

what is encephalitis?

Answer 25

inflammation of the brain

Question 26

causes- encephalitis?

Answer 26

most commonly caused by viral infection

CAUSES:
HIV
Viral- HSV 1 (most common
Bacterial
Fungal, parasitic

Question 27

presentation- encephalitis?

Answer 27

-insidious onset (sometimes sudden)
-meningismus
-stupar, coma
-seizures, partial paralysis
-confusion, psychosis
-speech, memory symptoms

Question 28

MRI- encephalitis?

Answer 28

-bilateral medial temporal involvement

-temporal lobe and adjacent parahippocampal gyrus will look brightest white

Question 29

LP- encephalitis?

Answer 29

LP
Viral - elevated lymphocytes, viral detection by CSF PCR

Limbic - antibodies may be identifiable

Question 30

treatment- encephalitis?

Answer 30

aciclovir (give before you even do tests)

Question 31

what is Kernigs sign?

Answer 31

Pain on resistance on passive knee extension with hips fully flexed

for diagnosing meningitis

KErnigs= Knee Extension painful

Question 32

what is Brudzinkis sign?

Answer 32

Knees and hips flex on bending the head forwards

-test for meningitis

brudziNKis= Neck flexion leads to Knee flexion

Question 33

CI for lumbar puncture?

Answer 33

-GCS <13
-Seizures
-Papilloedema
-Focal neurological signs
-Severe/ rapidly developing illness (rapidly evolving rash)

if any of these do a CT first

Question 34

management if LP cannot be done in <1 hour?

Answer 34

give antibiotics immediately

Question 35

prophylaxis for family of someone with meningitis?

Answer 35

ciprofloxin or rifampicin

Question 36

do you contact public health- meningitis

Answer 36

yes contact public health
-and make sure contacts receive oral ciprofloxin or rifampicin as prophylaxis

Question 37

Most common complicaion of meningitis?

Answer 37

sensorineural hearing loss

Question 38

Most common complicaion of meningitis?

Answer 38

sensorineural hearing loss