Meningitis

1. Meningitis

2. Definition
• Inflammation of meninges (membrane surrounding the brain and
spinal cord)
• Pachymeningitis : inflammation of dura
• Leptomeningitis : inflammation of arachnoid
• Common in children less than 4 years old
• Peak 3-8 months old
• Incidence of encephalitis related to vaccination in childhood

3. Etiology
• Neonates
• GBS,E.Coli,Staph. Aureus,Listeria Monocytogenes,Group A Streptococcus
• Infants
• GBS,E.Coli,Listeria Monocytogenes
• Children
• Neisseria Meningitides,Strep. Pneumonia,Haemophilus Influenza,Myco. TB,
Staph. Aureus
• School age children
• Neisseria Menigitides,Strep. Pneumonia

4. Pathogenesis
1. Nasopharynx > haematogenous > cross BBB > subarachnoid space
2. Direct through the skull from infected loci (parasinus/middle ear/
PNS/nose > meninges)
3. Direct spread following skull fractur
4. Direct inoculation into CSF
• Meningomyelocele
• Neurosurgical procedure

5. Clinical Features
• Neonatal : vague and non specific
• Fever
• Refuse to feed + vomit
• Irritable + drowsiness
• Irregular respirations
• Neck stiffness > rare and late findings
• Tense + bulging fontanelle > late course of illness

6. Clinical Features
• Infant
• Fever + vomiting
• Marked irritability + convulsion + somnolence
• Tense + bulging fontanelle > late course of illness

7. Clinical Features
• Children
• Fever + chills
• Headache + photophobia + vomiting
• Stiff neck + lethargy
• Convulsion + delirium + drowsiness + irritability

8. Physical Examination
• General
• GCS
• Level of consciousness
• Vital signs
• Febrile
• Shock
• Hypertension
• Bradycardia/apnea
• Head
• Bulging and tense fontanelles
• Eye
• papilledema
• Skin
• Purpuric rash (meningococcal rash)
• Brudzinki's : Knee automatically brought up toward body when neck is bent forward or
pain in the legs when bent
• Kernig's : Inability to straighten a child's knee after hip flexion 90 degree
• Focal neurological sign

9. Differential diagnosis
• Intracranial infection
• Brain abscess
• Cerebral malaria
• Metabolic disorder
• Acid-base disorder
• Inherited metabolic disease (urea cycle disorder and lactic acidosis)
• Seizure disorder
• Status epilepticus
• Hemiconvulsion-hemiplegia syndrome
• Increase ICP
• Tumor
• Hematoma
• Acute hydrocephalus
• Lead poisoning
• Subarachnoid haemorrhage

10. Investigations
• Full blood count
• BUSE
• Blood C&S
• Urine C&S
• RBS
• LP
• Imaging
• CT brain
• MRI
• Throat swab
• Rapid antigen test in body fluid
• CSR and Mantoux test

11. Lumbar puncture
Appearance Cell Type CSF:serum
glucose ratio
Protein (mg/dL)
Normal Clear 0-5 Mononuclear
cell
High >0.5 10-50
Bacterial Turbid 10-10000 PMN Low <0.4 High
Viral Clear or slightly
turbid
10-2000 Lymphocytes Normal Normal or high
TB and fungi Clear or slightly
turbid
10-1000 Lymphocytes Low High
Encephalitis Clear 10-2000 Lymphocytes Normal Normal or high

12. Management
• Supportive
1. Vital sign monitoring 4 hourly
2. Input and output chart
3. KNBM in unconscious
4. Fluid therapy : maintenance fluid
• If SiADH occur : reduce to 2/3 maintenance for initial 24h,may need more fluid if
dehydrated
5. Daily head circumference
6. Daily CNS assessment
7. Observe 24h after stopping therapy > no complications,discharged

13. Management
• General
1. Increase ICP : rapid administration of IV mannitol
2. Seizures : anticonvulsant drugs (IV diazepam in acute phase)
• Anti-microbial therapy
• 0-1 months : C.Penicillin + Cefotaxime for 3 weeks
• 1-3 months : C.Penicillin + Cefotaxime for 3 weeks
• >3 months : C.Penicillin + Cefotaxime or Ceftriaxone
• HiB : 10 days
• S.Pneumonia : 2 weeks
• N.Meningitides : 1 weeks

14. Management
• Steroid therapy
• Dexamethasone 0.15mg/kg 6hourly for 4 days or 4mg/kg 12hourly for 2 days
• Improve meningeal inflammation and reduce hearing impairment
• Tubercular meningitis
• Triple therapy : isoniazid + rifampicin + ethambutol ± pyrazinamide (excellent
penetration into CSF)

15. Follow-up
• Development of child
• Head circumference
• Occurrence of fit or behaviour abnormalities
• Assessment of vision,hearing and speech

16. Complications
• Meningococcemia – shock + DIVC
• Neurologic - hemi/quadriparesis,facial palsy or visual defects
• Seizures
• Subdural collection of fluid
• Arthritis(Hib)
• Buccal cellulitis
• Pericarditis
• Pneumonia

17. Prognosis
• Worse in younger patients
• Duration of illness prior to effective antibiotics
• More complications in HiB and Strep. Pneumoniae
• Worse when presence of focal sign

18. Prevention
• Immunization : N.Meningitis,Strep. Pneumonia,Hib
• Chemoprophylaxis : intrapartum ampiccilin for GBS,rifampicin for HiB
contact,azithromycin/ciprofloxacin for meningococcal carriage in
adult