Meningitis

Question 1

What are the common causative organisms of bacterial meningitis in different age groups?

Answer 1

Neonates - Group B steptococcus, Ecoli and other gram -ve, Listeriomonocytogenes (GBS from mothers vagina at birth - PROM is a risk factor)
1-6 months - Neisseria, streptococcus, haemophilis influenza
>6 years - Neiseria Meningitidis, Streptococcus

Question 2

What are the signs and symptoms of meningitis?

Answer 2

• fever
• neck stiffness
• vomiting
• headache
• photophobia
• altered consciousness
• if meningococcal septicaemia= non-blanching rash
  Other causes of bacterial meningitis do not usually cause the non-blanching rash.
• *Non-specificsigns and symptoms**
• hypotonia
• poor feeding
• lethargyhypothermia
• BULGING FONTANELLE (raised ICP)

Question 3

What specific tests are carried out?

Answer 3

Kernig’s test
- lying the patient on their back, flexing one hip and knee to 90 degrees and then slowly straightening the knee whilst keeping the hip flexed at 90 degrees. This creates a slight stretch in the meninges. Where there is meningitis it will produce spinal pain or resistance to movement

Brudzinski’s test
- lying the patient flat on their back and gently using your hands to lift their head and neck off the bed and flex their chin to their chest. In a positive test this causes the patient to involuntarily flex their hips and knees.

Question 4

What are the investigations?

Answer 4

1. Lumbar Puncture - NICE recommend alumbar punctureas part of the investigations for all children:
   > Under 1 month presenting with fever
   > 1 to 3 months with fever and are unwell
   > Under 1 year with unexplained fever and other features of serious illness
   contraindications:
   
   • focal neurological signs
   • papilloedema
   • significant bulging of the fontanelle
   • disseminated intravascular coagulation
   • signs of cerebral herniation
2. Blood culture - haematology and viralogy
3. Blood glucose - If the CSF glucose is

Question 5

What is the management for bacterial meningitis?

Answer 5

Community

• Meningitis with non blanching rash = IM/IV benzylpenicillin and transfer (check if true penicillin allergy)
• Transfer young people with suspected bacterial meningitis without non-blanching rash directly to hospital without antibiotics unless urgent transfer is not possible. Babies less than 72hrs old should be managed according to neonatal sepsis guidelines

1. DRUGS
   Under 3 months - cefotaxime+amoxicillin(amoxicillin coverlisteriacontracted during pregnancy)
   Above 3 months - ceftriaxone or cefutaxime - other wise displaces bilirubin from albumin binding sights
   - Vancomycin should be added to these antibiotics if there is a risk of penicillin resistant pneumococcal infection, for example recent foreign travel or prolonged antibiotic exposure.
   - N meningitidis: IV ceftriaxone 7d
   - influenza or suspected: IV ceftriaxone 10d
   - pneumoniae: IV ceftriaxone 14d
   - GBS: IV cefotaxmine 14d
   - monocytogenes: IV amoxicillin 21d + IV gentamicin for first 7d.
   - Gram -ve bacilli: IV cefotaxime 21d
   - Unconfirmed bacterial meningitis: <3m IV cefotaxime + amoxicillin 14d, >3m IV ceftriaxone 10d.
   - Confirmed meningococcal disease: IV ceftriaxone 7d.

Consult microbiology and paediatric infectious diseases about extending the duration of treatment, poor response and presence of effusion, abscess or concomitant intraventricular haemorrhage.

2. Observe RR, HR, BP, GCS/AVPU, CRT and saturations hourly for 4-6hrs. If doubt remains in children with rash and fever but no high-risk clinical manifestations, admit and treat with antibiotics. Ensure child is NBM from admission.
3. Give 0.15 mg/kg dexamethasone to a maximum dose of 10 mg, four times daily for 4 days to children over 3m if lumbar puncture reveals frank purulent CSF, CSF WBC >1000/microL, CSF WBC raised and protein >1g/L, bacteria Gram stain. Do not start dexamethasone more than 12hrs after starting antibiotics.
4. Manage complications such as seizure and raised ICP according to local protocols
5. Administer 15L oxygen by rebreathing mask. Prepare for intubation if there is threatened loss of airway patency
6. If present, correct dehydration using enteric fluids/feeds or IV 0.9% NaCl + 5% dextrose. Do not restrict fluids unless there is evidence of raised ICP or increased ADH secretion. Give maintenance fluids using the same isotonic solutions. In neonates, use dextrose 10%. Monitor fluids, UO and U&E
7. Meningococcal septicaemia: correct metabolic disturbances (hypoglycaemia, acidosis, hypokalaemia, hypocalcaemia, hypomagnesaemia, anaemia, coagulopathy). Give immediate bolus of 20 ml/kg sodium chloride 0.9% IV or IOover 10 minutes. If signs of shock persist, give a second bolus. If signs persist, discuss with intensivist. Consider vasoactive therapy using IV adrenaline or noradrenaline. Do not treat with high dose steroids. Only used low dose steroids when directed by an intensivist.
8. Once stable, offer information about accessing future care. Inform the GP, health visitor and school nurse. Offer formal audiological assessment within 4w of stabilisation and offer children with profound deafness an urgent assessment for cochlear implants. Offer paediatric review in clinic with the results of testing and consider skin, neurological, renal, orthopaedic and psychosocial complications also.
9. Test children for complement deficiency if they have had more than one episode of meningococcal disease or an episode caused by serogroups other than B or a history of other serious bacterial infections. Refer these children to paediatric infectious disease.

Post Exposure Prophylaxis

• risk is highest for people that have had close prolonged contact within the7 daysprior to the onset of the illness. The risk decreases 7 days after exposure - if no symptoms have developed 7 days after exposure they are unlikely to develop the illness.
• The usual antibiotic choice for this is asingle doseofciprofloxacin. It should be given as soon as possible and ideally within 24 hours of the initial diagnosis.

Question 6

What are the most common causes of viral meningitis?

Answer 6

1. Enterovirus (Coxackie and Echovirus)
2. Herpes simplex virus(HSV) - can cause both encephalitis and meningitis
3. Varicella zoster virus (VZV)

A sample of the CSF from the lumbar puncture should be sent forviral PCRtesting.

Viral meningitis tends to be milder than bacterial and often only requires supportive treatment

Question 7

How do lumbar puncture results differ between bacterial and viral meningitis?

Answer 7

Normal

• clear
• protein 0.2-0.4 g/L
• glucose 0.6-0.8
• WCC <5

Bacterial

• cloudy
• protein >1.5 g/L
• glucose < 0.5
• WCC >1000 (neutrophils)

Viral

• clear
• protein mildly raised/normal
• glucose 0.6-0.8
• WCC >1000 (lymphocytes)

Question 8

What are the complications of meningitis?

Answer 8

• Hearing loss is a key complication
• Seizures and epilepsy
• Cognitive impairment and learning disability
• Memory loss
• Cerebral palsy, with focal neurological deficitssuch as limb weakness or spasticity