This topic appears in the curriculum under knowledge of '...conditions likely to deteriorate to respiratory or cardiac arrest in children e.g. meningococcal sepsis and describes their initial management'.
It featured as an SAQ in 2018 (64% pass rate), with overall positive examiner feedback.
A CRQ in March 2022 (83% pass rate) had similarly positive feedback, although wanted more knowledge on further steps in managing septic shock.
Meningitis describes inflammation of the meninges, and is generally used synonymously with some infection of the meninges be it bacterial, viral, fungal or by other micro-organisms e.g. amoeba
Delays in recognition and treatment of bacterial meningitis can be fatal (it is the leading infectious cause of death in early childhood) or result in permanent neurological injury
Of note, a positive vaccination history does not exclude meningitis as it does not protect against all causative organisms
Neonates (<28 days)
Streptococcus agalactiae (Group B strep.)
E. coli
Streptococcus pneumoniae
Listeria monocytogenes
>3 months
Neisseria meningitidis
Haemophilus influenzae type b
Streptococcus pneumoniae
M. tuberculosis
Viral causes
Enterovirus
Herpes simplex virus
Varicella zoster virus
HIV
Lymphocytic choriomeningitis virus
EBV
CMV
Mumps
The meningeal inflammation occurs particularly in the pia and arachnoid mater, associated with the invasion of bacteria into the subarachnoid space
Bacterial invasion into the CNS can occur due to:
High-grade bacteraemia, with invasion of microorganisms into the CNS at highly vascularised areas such as the choroid plexus or leptomeningeal vessels
Local infection e.g. following sinusitis
Dural defects such as iatrogenic (e.g. post-surgical), traumatic (e.g. base of skull fracture) or spontaneous
Bacterial invasion results in endothelial activation and leucocyte infiltration, which limit bacterial invasion but may also result in neuronal damage and adverse outcomes
The majority (60%) of patients demonstrate features of both meningitis and sepsis
Some present with just sepsis (25%) or meningitis without sepsis (15%)
Classic symptoms
95% of patients will have at least two of these four classic symptoms
Fever
Headache
Neck stiffness
Altered mental status
Meningism (the triad of headache, neck stiffness and photophobia) may be seen in older children but is rarely seen in younger ones
Constitutional features
Inconsolability
Lethargy
Listlessness and unrousable
Irritable, confused, aggressive
Myalgia, arthralgia
Reduced oral intake/poor feeding
Vomiting
Nausea
Neurological features
Altered mentation
Fluctuating conscious level
Drowsiness or depressed consciousness
Vacant staring expression (infants)
Cranial nerve palsies
Altered pupillary size/reactions
Photophobia
Focal neurological deficits
Hemiparesis
Aphasia
Seizures
Coma
Cushing's triad
Bulging fontanelle (late sign)
Papilloedema (late sign)
Dermatological features
Non-blanching rash
Digital ischaemia
Purpura fulminans (meningococcal sepsis)
Features of sepsis
Hypotension, particularly low diastolic pressure as low systolic pressure may be a late sign
Tachycardia
Tachypnoea
Shock and poor end-organ perfusion e.g. lactate >2, CRT >3s
Myocardial depression (meningococcal sepsis)
Bloods
FBC for white cell count WCC
U&E, LFT, Bone profile
CRP
Glucose (immediately prior to LP)
Clotting screen
Microbiology
Whole blood real-time PCR for N. meningitidis (although NB negative PCR does not exclude disease)
Blood cultures
Lumbar puncture
If there are neurological symptoms or other contraindications (cardiorespiratory instability, coagulopathy), perform only once CT has been done to exclude other aetiology or causes of raised ICP
Do not delay antibiotics to perform LP although ideally perform LP first
Bottles:
Virology specimen for PCR
Protein
Micro sample for MC&S
Glucose
Features
Feature of CSF
Results in meningitis
Appearance
Cloudy/turbid
Opening pressure
Elevated
CSF WBC count
Significantly elevated in bacterial meningitis Neutrophils predominate in early TB or viral meningitis (esp. enterovirus) Lymphocytes predominate in fungal, late TB or HSV meningitis
CSF protein
Significantly elevated in bacterial and tuberculous meningitis Somewhat raised in viral and fungal meningitis
CSF glucose
↓ compared to normal value of 60-75% of serum glucose May be normal in viral inc. HSV meningitis
Gram stain
Positive for gram negative cocci i.e. Neisseria meningitidis
PCR
Positive e.g. for meningococcus or streptococcus
Neonatal viral sepsis screen if <1 month
Eye, throat and rectal swabs
Test for HSV, adenovirus and enterovirus PCR
Infants >1 month
Throat swabs for respiratory PCR
Stool sample for enterovirus PCR
If uncertainty over source of sepsis consider urinalysis, CXR etc.
Radiology
CT brain usually indicated to detect alternative intracranial pathology if neurological concerns
Carried out to exclude complications of meningitis which will make LP risky if there is clinical suspicion of raised ICP
E.g. subdural collections as in H. influenzae meningitis
E.g. obstructive hydrocephalus in M. tuberculosis meningitis
E.g. evidence of raised ICP such as ventricular effacement
May show leptomeningeal enhancement
Most commonly normal
Initial resuscitation
Monitoring in an appropriate environment, including SpO2, NIBP, urine output and glucose measurement
Provide oxygen to optimise DO2 e.g. initially high flow oxygen via non-rebreathe mask but may require escalation to non-invasive or invasive ventilatory strategies
IV (or IO) access x 2
Fluid resuscitation with balanced crystalloid boluses of 5-20ml/kg titrated to peripheral perfusion, age-appropriate haemodynamic indices and lactate
Anticipate a total of up to 40-60ml/kg fluid boluses in the first hour of resuscitation in sepsis
If no resolution after 40ml/kg of boluses then manage as fluid-refractory shock
Anti-microbials
Urgent antibiotics within 1hr if suspicion of bacterial meningitis; each hour of delay reported to increase unfavourable outcome by 10-30%
IV antibiotics
<1 months: IV cefotaxime 50mg/kg + IV amoxicillin 60mg/kg
>1 months: IV ceftriaxone 80mg/kg
± appropriate Herpes simplex treatment if suspected viral meningitis e.g. IV aciclovir 20mg/kg
± PO/NG rifampicin 10mg/kg for those who are moribund (e.g. PICU), have suspected pneumococcal resistance or have recent foreign travel
± appropriate TB treatment
Duration of therapy is guided by clinical picture and isolated pathogen:
Meningococcal: 7 days
Streptococcal or Haemophilus: 14 days
Listeria or Group B strep: 14-21 days
Gram negative bacteria e.g. E.coli: 21 days
Corticosteroids
Dexamethasone 0.15mg/kg (max 10mg/dose) in suspected bacterial meningitis
Give QDS for 4 days if CSF frankly purulent, CSF WCC >1,000/μL, protein >1g/L or gram stain positive
Ideally start dexamethasone before antibiotics
Do not start dexamethasone >12hrs after starting antibiotics
May reduce severe neurological sequelae including hearing loss, and mortality rate (in those with pneumococcal meningitis)
Consider stopping if an organism other than S. pneumoniae or M. tuberculosis is identified
May need hydrocortisone 25mg/m2 QDS for refractory shock on PICU
Management of fluid-refractory shock
Call local tertiary unit for advice
Start peripheral adrenaline 0.1μg/kg/min with close monitoring of the limb into which it is being infused
Prepare for invasive ventilation in order to gain control and facilitate central access
Once central access obtained, use either:
Adrenaline 0.1μg/kg/min (up to 1μg/kg/min) if 'cold' shock i.e. cold peripheries, narrow pulse pressure and suggestion of poor cardiac output
Noradrenaline 0.1μg/kg/min (up to 1μg/kg/min) if 'warm' shock i.e. vasodilated, wide pulse pressure
If still hypotensive then deem inotrope-resistant shock and consider:
Hydrocortisone
Management of toxic shock syndrome e.g. IV clindamycin + IVIg
Anaerobic cover e.g. metronidazole for gut pathology
Investigation for other causes of shock e.g. haemorrhage, adrenal insufficiency, hypothyroidism
Mortality in range 5-10% within 48hrs even with early diagnosis and institution of therapy
Hearing loss (8%); arrange audiology review as soon as possible after diagnosis of bacterial meningitis (within 4 weeks)