Meningitis and encephalitis in a child Flashcards
What CSF WCC is indicative of meningitis in an older child and infant?
Older - >5
Infant - >20
What are the normal vital signs for different age groups of paediatric patients?
What are the causes of meningitis in neonates, children and young adults?
Neonatal to 3 months
- Group B Streptococcus: usually acquired from the mother at birth. More common in low birth weight babies and following prolonged rupture of the membranes
- E. coli and other Gram -ve organisms
- Listeria monocytogenes
- Also: staph aureus, pneumococcus
1 month to 6 years
- Neisseria meningitidis (meningococcus)
- Streptococcus pneumoniae (pneumococcus)
- Haemophilus influenzae
Greater than 6 years
- Neisseria meningitidis (meningococcus)
- Streptococcus pneumoniae (pneumococcus)
What is the management of neonatal meningitis (<28 days)?
- Send blood and CSF cultures
- Start broad spectrum antibiotics - cefotaxime and amoxicillin…
-
until result of CSF culture - then if
- GBS (gram +ve)- benzylpenicillin 14 days AND gentamicin 5 days
- Listeria - amoxicillin, gentamicin
- Gram -ve - cefotaxime only
- Other gram +ve - seek advice
What are the most common causes of bacterial meningitis in children and young people ages 3 months and over?
- Meningococcus
- Penumococcus
- Hib
What is the most common cause of neonatal meningitis?
- Streptococcus agalactiae* a.k.a. GBS
- (also E coli, Listeria, and S pneumonia*)
What is the pathophysiology of bacterial meningitis?
Usually bacteria live in the URT and can cause invasive disease when acquired by a susceptible person
The infection then travels to the surface of the brain via the bloodstream
How does meningococcal disease present usually?
- Bacterial meningitis (15% of cases)
- Septicaemia (25% of cases)
- Combination of both (60% of cases)
What are the signs specific to bacterial meningitis and meningococcal septicaemia?
- non-blanching rash - check soles of feet, palms of hands and conjunctivae
- neck stiffness
- altered GCS - confusion, delirium, drowsiness
- cap refill >2 seconds
- mottled
Not in septicaemia:
- Kernig’s sign
- Brudzinski’s sign
- photophobia
- bulging fontanelle (<2 years)
- focal neurological deficits
- seizures
What are the common non-specific signs/symptoms in bacterial meningitis/meningococcal septicaemia?
- may be non-specific
- shock
- petechial rash
- fever
- vomiting/nausea
- irritability
- lethargy
- refusing feeds
- muscle aches/joint pain
- respiratory distress
- ill appearance
https://www.nice.org.uk/guidance/cg102/resources/meningitis-bacterial-and-meningococcal-septicaemia-in-under-16s-recognition-diagnosis-and-management-pdf-35109325611205 - page 14-16 table of symptoms
What features of the petechial rash would force you to give antibiotics straight away?
Petechial rash which:
- starts to spread
- becomes purpuric
What are the contraindications to LP?
- Raised ICP
- Shock
- Extensive/spreading purpura
- Convulsions
- Coagulation abnormalities (platelets <100x 10^9/L or on anticoags)
- Local infection at site
- Respiratory insufficiency
What are the signs of raised ICP?
- reduced or fluctuating consciousness (GCS <9 or -3)
- relative bradycardia and hypertension
- focal neurological signs
- abnormal posturing
- unequal, dilated or poorly responsive pupils
- papilloedema
- abnormal ‘doll’s eye’ movements
How much fluids should you give in shock secondary to meningococcal septicaemia (confirmed/suspected)?
- 20ml/kg of 0.9% sodium chloride over 5-10mins
- IV or IO
- repeat if necessary and reassess
- max 3 times before senor help
If shock persists past the second fluid bolus in meningococcal septicaemia, what is the management?
- Prepare to give third bolus
- Call for anaesthetic help for intubation and ventilation
- Start vasoactive drugs
- Investigate urea and electrolytes
What is the management of meningococcal disease in <3 month old?
IV cefotaxime plus amoxicillin for 7 days
Do not give steroids
What is the management of meningococcal disease in children >3 months and young people?
IV ceftriaxone for 7 days
When should you consider cosrticosteroids in bacterial meningitis/meningococcal septicaemia?
If aged >3 months and..
- frankly purulent CSF
- WCC >1000/microlitre in CSF
- protein conc >1g/litre
- bacteria on gram stain
ONLY give if within 4 hours of starting antibiotics
What are the long-term complications if bacterial meningitis and meningococcal septicaemia?
- Deafness - offer hearing test at 4-6 weeks and cochlear implants if necessary
- Orthopaedic complications - bone and joint damage
- Skin complications - scarring from necrosis
- Neurological and developmental problems
- Renal failure
What does AVPU stand for?
- Alert
- Voice
- Pain
- Unresponsive
Should be done hourly in meningococcal disease.
Is meningitis/meningococcal septicaemia notifiable?
Yes - must inform an officer of the local authority if you suspect it. Required under the Health Protection (Notification) Regulations 2010
How do you manage suspected meningococcal disease pre-hospital?
If non-blanching rash: give IV/IM benzylpenicillin but do not delay transfer to hospital/secondary healthcare setting by calling 999
If no rash: transfer without giving antibiotics
NB: ensure to allergy to penicillin.
Which bloods should be carried out in meningococcal disease?
- FBC
- CRP
- Coagulation screen
- Blood culture - PCR for N meningitidis
- Blood glucose
- Blood gas
Which markers in blood prompt to immediate treatment with ceftraixone in suspected meningococcal disease? What if these are absent?
Raised CRP, WBC (especially neutrophils)
HOWEVER, absence does not exclude diagnosis.
If the child is assessed as low risk of meningococcal disease, what is the management? What if a non-spreading petechial rash is present?
Discharge and safety net (if child appears ill to parent/carer then advise return to hospital)
If the rash does not spread after 24 hours then consider other diagnoses, especially if the child is not ill. Do FBC and coag screen.
How do you detect N. meningitidis in the blood?
real-time PCR on an EDTA sample
What is the management, if CRP/WCC is raised but CSF is non-specific or shows a viral profile?
Treat as bacterial meningitis
Should you use skin samples in the diagnosis of meningococcal disease?
“Do not use any of the following techniques when investigating for possible meningococcal disease: skin scrapings, skin biopsies, petechial or purpuric lesion aspirates (obtained with a needle and syringe)” - NICE
What do you look at in the CSF? How fast do results come back?
- WBC counts
- total protein
- glucose concentration
Within 4 hours
What WCC in CSF point towards bacterial meningitis?
>20cells/microlitre in neonates
>5 cells/microlitre OR >1 neutrophil/microlitre in young people/children
If CSF is normal but you suspect meningitis, what is a differential diagnosis?
Herpes simplex encephalitis - give appropriate antiviral
When should you do a CT scan in suspected meningococcal disease? Is CT reliable for showing raised ICP?
CT not reliable for identifying raised ICP
Do CT to detect alternative intracranial pathology
- reduced/fluctating consciousness (<9 or -3 or more)
- focal neurological signs
What is the antibiotic of choice for meningococcal disease in children >3 months?
IV ceftriaxone
If a child has had prolonged antibioic exposure in the last 3 months, what antibiotic should you add to the meningococcal treatment?
Vancomycin
When should ceftriaxone not be used?
In premature infants or babies with jaundice, hypoalbuminaemia or acidosis as it can exacerbate hyperbilirubinaemia.
Also if being given calcium-containing infusions (use cefotaxime instead).
What is the duration of treatment for meningococcal disease?
7 days
What are the antibiotics of choice and their durations for these infections:
- H influenza or unconfirmed in 3 month old
- S pneumoniae in 6 yr old
- GBS in 2 month old
- L monocytogenes in 2 month old
- Gram -ve bacilli in 1 month old
- unconfirmed in 2 month old
- IV ceftriaxone 10 days
- IV ceftriaxone 14 days
- IV cefotaxime 14 days
- IV amoxicillin 21 days AND gentamicin for first 7 days
- IV cefotaxime 21 days
- IV cefotaxime plus amxicillin/ampicillin for 14 days
What are the vasoactive therapies of choice if shock perisists after 2 fluid boluses (>40ml/kg)?
IV adrenaline or IV noradrenaline or both
What type of oxygen should you give in respiratory distress in meningitis?
15 L face mask oxygen via reservoir rebreathing mask
What are the indications for tracheal intubation and mechanical ventilation in meningococcal disease?
- threatened or actual loss of airway patency
- already needing bag-mask ventilation
- increasing work of breathing
- hypoventilation/apnoea
- respiratory failure features (Cheyne-Stokes breathing, PaO2 <13kPa, or low sats on air, hypercapnia >6kPa)
- continued shock
- raised ICP
- impaired GCS
- intractable seizures
- need for ICU
What immune deficiency may cause recurrent meningococcal disease?
Complement deficiency
What is the difference between encephalitis and meningitis?
Encephalitis is inflammation of the brain substance, although meninges may also be affected.
Meningitis is inflammation of the meninges.
Name 3 different causes of encephalitis.
- Direct invasion by neurotoxic virus e.g. HSV
- Delayed brain swelling after dysregulated immunological response to an antigen e.g. virus like chickenpox a.k.a postinfectious encephalopathy
- Slow virus infection like HIV or subacute sclerosing panencephalitis (SSPE) following measles
What types of encephalitis are caused by these infections?
- measles
- chickenpox
measles - subacute sclerosing panencephalitis (SSPE)
chickenpox - postinfectious encephalitis
What is the clinical presentation which might suggest encephalitis?
Insidious onset with behavioural change
Is it possible to distinguish encephalitis from meningitis clinically? What about infectious and non-infectious/metabolic encephalitis?
Usually not - may both present with fevers, altered consciousness, seizures
May both present with similar features
What are the most common causes of encephalitis in the UK and worldwide?
UK
- enteroviruses
- respiratory viruses (e.g. influenza)
- herpesviruses (e.g. HSV, VZV, HHV-6)
Worldwide
- Mycoplasma
- B. burgdorferi (Lyme disease)
- rickettsial infectoins (e.g. Rocky mountain spotted fever)
- Arboviruses
What is the management of encephalitis in all children?
high-dose IV aciclovir until HSV can be ruled out as this can have long-term consequences
(NB: most will not have skin signs of HSV)
What is the management of proven HSV encephalitis?
3 weeks of IV aciclovir
How do you investigate encephalitis?
- Check CSF for HSV using PCR
- CT/MRI may show focal changes e.g. in HSV, it is destructive particularly within the temporal lobes either unilaterally or bilaterally
- HSV antibody detection in CSF (after a few days)
What is the prognosis if HSV encephalitis is left untreated?
70% mortality and survivors have severe neurological sequelae
