Infections - Meningitis

Question 1

what is meningism?

Answer 1

The clinical signs and symptoms suggestive of meningeal irritation

Question 2

where does CSF run between?

Answer 2

arachnoid and pia matter

Question 3

a meningeal encephalitis is ?

Answer 3

inflammation of brain parenchyma

Question 4

Signs & Symptoms in older children (8)

Answer 4

Fever
Headache
Photophobia
Neck stiffness (nuchal rigidity)
Nausea & vomiting
Reduced GCS
Seizures
Focal neurological deficits (ICP or venous sinus thrombosis)

Question 5

Signs & Symptoms in babies and young infants ?

Answer 5

Fever or hypothermia
Poor feeding
Vomiting
Lethargy
Irritability
Respiratory distress
Apnoea
Bulging fontanelle - raised ICP

Question 6

what is Apnoea?

Answer 6

pause in breathing lasting more than 20 seconds

Question 7

Palpable resistance to neck flexion is known as?

Answer 7

Nuchal Rigidity (Neck Stiffness)

Question 8

2 clinical signs/ tests to do on child? - what do they do

Answer 8

Brudzinski’s sign
-Hips and knees flex on passive flexion of the neck

Hips and knees flex on passive flexion of the neck

• Pain on passive extension of the knee
• RESISTANCE - other leg often flexes

Question 9

Causes of Childhood Meningitis (in the post-vaccine era)?

Answer 9

• Bacterial (4-18%)
• Viral – Mainly Enterovirus (54-88%)

Fungal - Neonates/Immunocompromised

Unknown/aseptic (40-76%)

Question 10

Most common pathogens in neonate?

Answer 10

Group B Streptococcus
Escherichia coli
Listeria monocytogenes

Question 11

Most common pathogens in older infants and children?

Answer 11

Streptococcus pneumoniae
Neisseria meningitidis
Haemophilus influenzae type b (Hib)

Question 12

what organism Is Haemophilus influenzae

• where is it carried?

Answer 12

non-motile, gram-negative coccobacillus

= Nasopharyngeal carriage

Question 13

Encapsulated H. influenzae

- give features (5)

Answer 13

Resist phagocytosis & complement mediated lysis

6 serotypes (a-f)

Hib main cause of invasive H. influenzae infection

Bacteraemia, Meningitis, Epiglottitis, Pneumonia

RF – asplenia, sickle cell disease, antibody deficiency

Question 14

Main serotype that causes invasive Haemophilus influenzae infection?

Answer 14

B

- HIB B

Question 15

Non-encapsulated Haemophilus influenzae is a common cause of?

Answer 15

otitis media & sinusitis

invasive infection rare

Question 16

main serotypes of Meningococcal Disease- most common type?

Answer 16

ABCWY

• type B

Question 17

Neisseria meningitidis organism type?

- where is it carried?

Answer 17

Gram negative diplococcus

• Nasopharyngeal carriage
  Transmission via respiratory secretions

Question 18

increased risk of infection of Neisseria meningitidis after what?

Answer 18

viral URTI

Question 19

Neisseria meningitidis produces…?

Answer 19

Endotoxin (LPS)

Question 20

Invasive Meningococcal Disease - Risk Factors

Answer 20

Age <1 year or 15-24 years

Unimmunised

Crowded living conditions

Household or kissing contact

Cigarette smoking (active or passive)

Recent viral/Mycoplasma infection

Complement deficiency

Question 21

Complement deficiency common risk factor of?

Answer 21

Invasive Meningococcal Disease

Question 22

Invasive Meningococcal Disease - main clinical sign?

Answer 22

Petechial/Purpuric Rash

- non- blanching rash then progresses to petechial

Question 23

When the purpura develops what does it become?

Answer 23

Purpura fulminans

• big bruise like lesions, poor tissue perfusion and necrosis

Question 24

Significant long term sequelae of Invasive Meningococcal Disease?

Answer 24

Amputation (14%) - necrosis
Scarring (48%)
Hearing Loss
Cognitive impairment/epilepsy

Question 25

Streptococcus pnuemoniae (Pneumococcus) - what organism is it?

Answer 25

- Gram positive, lancet-shaped, diplococcus | - Facultative anaerobe

Question 26

what does Streptococcus pnuemoniae inhibit?

Answer 26

neutrophil phagocytosis | complement mediated cell lysis

Question 27

where does Streptococcus pnuemoniae (Pneumococcus) colonise? what predisposes you?

Answer 27

nasopharynx Preceeding URTI RF for invasive infection

Question 28

Invasive Pneumococcal Disease risk factors (10)

Answer 28

``` Age <2 years Cigarette smoking (active or passive) Recent viral URTI Attendance at childcare Cochlear implant Sickle cell disease Asplenia HIV infection Nephrotic syndrome Immunodeficiency/Immunosuppression ```

Question 29

neurological complications of pneumococcal meningitis ?

Answer 29

``` Hydrocephalus Neurodisability Seizures Hearing loss Blindness ```

Question 30

Management of Meningitis - the basics

Answer 30

Airway Breathing Circulation – 20ml/kg fluid bolus, inotropes DEFG – ‘don’t ever forget glucose’ 2ml/kg 10% dextrose Antibiotics 3rd generation cephalosporin (e.g. Cefotaxime/Ceftriaxone) add IV Amoxicillin if <1m old

Question 31

investigations : blood

Answer 31

``` FBC (leukocytosis, thrombocytopaenia) U&Es, LFTs CRP Coagulation screen (DIC) Blood gas (metabolic acidosis, raised lactate) Glucose Blood culture Meningococcal/Pneumococcal PCR ```

Question 32

Signs of raised ICP? - do not give a lumbar puncture with any of these signs !!

Answer 32

- GCS <9 - Abnormal tone or posture - HTN & Bradycardia - Pupillary defects - Papilloedema - Focal neurological signs - Recent seizure - Cardiovascularly unstable - Coagulopathy - Thrombocytopenia - Extensive or extending purpura

Question 33

What gives the diagnosis?

Answer 33

lumbar puncture | - give before antibiotic if possible

Question 34

what will you find on a lumbar puncture?

Answer 34

``` Turbid or purulent High opening pressure - raised WCC (polymorphs) - raised Protein- - decreased Glucose (<50% serum ```

Question 35

why do we send a CSF sample??

Answer 35

``` Microscopy Gram Stain Culture Protein Glucose Viral PCR ```

Question 36

what organism responds faster to antibiotics?

Answer 36

Neisseria meningitidis