Acute meningoencephalitis Powerpoint presentation. It comprises of acute meningitis and acute encephalitis, their clinical features, physical assesment, diagnosis and treatment.

1. Acute Meningoencephalitis
Intern. Sunder Chapagain
1

2. Acute Meningoencephalitis
• meningoencephalitis is an acute inflammatory
process involving the meninges and, to a variable
degree, brain tissue.
• Acute Bacterial Meningitis
• Acute Viral Meningoencephalitis
2

3. 3

4. Acute bacterial meningitis
• Etiology
4

5. Aseptic meningitis
• Viral
– Enterovirus (Echovirus, Coxsackie virus, Polio)
– Herpes Simplex Virus-2
– Mumps: The commonest complication
– Lymphocytic choriomeningitis virus
• Fungal (in imuunocompromised)
– Cryptococcus neoformans
– Histoplasmosis, Candidiasis, Blastomyces
5

6. • Parasitic
– Toxoplasmosis
– Cysticercosis
– Amoebiasis
• Miscellaneous
– SLE
– Leukemia
– Lymphoma
6

7. Risk Factors
• Age
• Low socioeconomic status
• Head trauma
• Splenectomy
• Chronic diseases
• Children with facial cellulitis, periorbital cellulitis, sinusitis and
septic arthritis
• Maternal infection and pyrexia at the time of delivery.
7

8. 8

9. 9

10. Clinical features
Newborn & Infants: non-specific
• Fever
• Irritability
• Lethargy
• Vacant stare
• Poor tone
• Poor feeding
• High pitched cry
• Bulging anterior fontanelle
• Convulsions
• Opisthotonus
10

11. Older children
11

12. • Seizures
• Alteration in mental status
• Hypotension, fever or Hypothermia,
Tachycardia (Septic shock)
• Bleeding, Renal dysfunction (DIC)
12

13. Increased intracranial pressure (ICP)
• Papilledema
• Cushing’s triad
– Bradycardia
– Hypertension
– Cheyne-Stokes Breathing
• Projectile vomiting
• Headache

14. Physical examination
•Neck rigidity
•Focal neurological signs
•Ptosis
•Cranial nerve palsies
•Bulging fontanel

15. TB meningitis
• Children 6 months – 5 years
• Local microscopic granulomas on meninges
• Meningitis may present weeks to months after
primary pulmonary process
• CSF:
– Profoundly low glucose
– High protein
– Acid-fast bacteria (AFB stain)
– PCR
• Steroids + antitubercular agents
– (2HRZE+ 10 HR) WITH steroid for 4-6 weeks
15

16. Stages
• Stage 1: stage of invasion
– Low grade fever, loss of appetite, vomiting,
headache, photophobia, irritable, restless
• Stage 2: Stage of meningitis
– Neck rigidity, focal neurological deficits, isolated
cranial nerve palsies, loss of sphincter control
• Stage 3: Stage of coma
– Loss of consciousness, altered respiratory pattern,
dilated pupils, ptosis, ophthalmoplegia, coma
16

17. Neisseria meningitis
(Meningococcemia)
• Neisseria meningitidis: serotype Grp B
commonest
• Endotoxin causes vascular damage
vasodilatation, third spacing, severe shock
• Severe complication:
Waterhouse-Friderichsen syndrome: massive
haemorrhage of adrenal glands secondary to
sepsis: adrenal crisis-low B.P, shock, DIC,
purpura, adreno-cortical insufficiency
17

18. Morbiliform, non blanching
petechiae to purpura
involving mostly extensor
surfaces Tumbler test 18

19. Investigations
• Complete blood count
• C- Reactive Protein
• Renal function test
• Serum glucose
• Blood culture and
sensitivity
• If tubercular suspected
– PCR
– Chest X-ray
– Mantoux test
• Arterial blood gas
• Fundoscopy
• CT scan
19

20. CSF analysis
20

21. Management
Medical emergency
• Early diagnosis essential
• Immediate optimum treatment
• Intensive supportive therapy
• Rehabilitation
• Prophylaxis to family
• Notification to Public Health
21

22. Treatment
• Managed in Intensive Care Unit
• Manage airway, breathing and circulation first
• Management of raised ICP
• Fluid management
• Dexamethasone: only in Pneumococcal and H.
Influenzae B, given 1-2 hours before antibiotics
• Antibiotics
• Inotropes: increasing aortic diastolic pressure and
improving myocardial contractility
22

23.  ICP treatment
• 3% NaCl, 5 cc/kg over ~20
minutes
• May utilize osmotherapy
(Mannitol) - if serum
osmolarity <320 mOsm/L
• Mild hyperventilation
– PaCO2 <28 may cause
regional ischemia
– Typically keep PaCO2 32-38
mm Hg
• Elevate head end of bed by
30o

24. Fluid management
• Restore intravascular volume & perfusion
• Monitor serum Na+ (osmolality, urine Na+):
– If serum Na+ <135 mEq/L then fluid restrict
(~2/3x), liberalize as Na+ improves
– If severely hyponatremic, give 3% NaCl
• SIADH
– 4 - 88% in bacterial meningitis
– 9 - 64% in viral meningitis
• Diabetes insipidus
• Cerebral salt wasting
24

25. Antibiotics
• Best started within 60 min
• Empirical therapy
• Meningococcal meningitis
– Benzyl penicillin 400-500,000 units/kg/day q 4 hour
• Pneumococcus/ H. influenza
– Ampicillin (if penicillin susceptible) 300 mg/kg/day IV
q6 hour
– Ceftriaxone (if penicillin resistant) 100-150 mg/kg/day
q12 hour
– Cefotaxime 150-200 mg/kg/day q8 hour
– Vancomycin 60 mg/kg/day
25

26. Meningitis - Treatment duration
• Gram negative organisms: 21 days
• Pneumococcal (ampiclox/ceftriaxone): 10-14 days
• H influenza: 7-10 days
• Meningococcal: 7 days
• No growth: 7-10 days
• The CSF should be sterile within 24–48 hr of
initiation of appropriate antibiotic therapy.
26

27. Dexamethasone use in meningitis
• Consider if
– H. influenza & Streptococcus pneumoniae
– > 6 wks old
• Dose: 0.6 mg/kg/day in 4 divided doses for 2 days
• MOA:
–  local synthesis of TNF-, IL-1, PAF & prostaglandins resulting in  BBB
permeability,  meningeal irritation
•  incidence of hearing loss
• May adversely affect the penetration of antibiotics into CSF
• May decrease fever, giving false impression of improvement
27

28. Prophylaxis
• Rifampicin:
– Children 5mg/kg bd x 2 days
– Adults: 600 mg bd x 2 days
• Pregnant contact:
– Cefuroxime IM x 1 dose
28

29. Meningitis – Early complications
• Encephalitis
• Septic shock
• DIC
• Abscess
• SIADH
• Subdural effusion or
empyema ~30%
• Dural sinus
thrombophlebitis
• Stroke

30. Intermediate
• Hydrocephalus
• Cranial nerve palsy
Late
• Cerebral palsy
• Hearing loss
• Learning disability
30

31. Acute Encephalitis
• Encephalitis is an acute inflammatory process
affecting the brain
• Viral infection is the most common and important
cause, with over 100 viruses implicated worldwide
• Symptoms
– Fever
– Headache
– Behavioral changes
– Altered level of consciousness
– Focal neurologic deficits
– Seizures
31

32. Etiology
Non-Arbo viral
• Herpes viruses (sporadic)
– HSV-1, HSV-2
– varicella zoster virus
– cytomegalovirus
– Epstein-Barr virus
– human herpes virus 6
• Adenoviruses
• Influenza A
• Enteroviruses, poliovirus
• Mumps
• Rabies
Arbo-Viral (epidemic)
• Flaviviridae
– Japanese encephalitis
– St. Louis encephalitis
– West Nile
• Togaviridae
– Eastern equine encephalitis
– Western equine encephalitis
32

33. – Herpes simplex virus (HSV)
• the most common etiology of acute sporadic
encephalitis
– Arboviruses – arthropod-borne virus
• outbreaks in summer time…mosquitos and ticks
– Varicella zoster virus (VZV)
• immunosuppressed patients
33

34. Japanese encephalitis
• Most important cause of arboviral
encephalitis worldwide
• Transmitted by culex mosquito, which breeds
in rice fields
• Commonly involve Basal ganglia: Extra
pyradimal symptoms
• Post-immunization: Measles, Mumps
34

35. Herpes Simplex Encephalitis
• Primary infection: On the mucosa of
oropharynx, mostly asymptomatic
• Following primary infection, a latent
infection in trigeminal ganglion
• Inflammation and necrotizing lesions in
– Inferior and medial temporal lobe
– Orbito-frontal lobe
– Limbic structures
35

36. • Evolve over several days or acutely
• Fever, headache, confusion, stupor, coma,
seizures, status epilepticus
• Personality changes, irritability, delirium
• Temporal lobe seizures: Gustatory or olfactory
hallucinations, anosmia
36

37. CSF Analysis
• Increases CSF pressure
• Cell count: 10-500 cells/mm3
• Lymphocyte predominance
• Erythrocytes (in 80% of the cases)
• Normal CSF findings in 10%
• Xanthochromia: Due to lysis of RBC
• Glucose (mg/dl): normal or low
• Protein (mg/dl): >50 mg/dl
• HSV PCR: For the first 24-48 hours, detecting HSV DNA
by PCR in CSF:
– specific (100%) and
– sensitive (75-98%)
37

38. Neuroimaging
• Contrast Enhanced MRI
• Sensitive for early period HSV encephalitis
• Edema in orbitofrontal and temporal regions
• CT Scan
– Less sensitive than MRI
• EEG
– If seizures are the features
38

39. Treatment
• If shock/hypotension exists, crystalloid
infusion
• If unconscious, provide airway/breathing
• Seizure, lorazepam 0.1 mg/kg, IV
• Acyclovir IV, 14 – 21 days
– Neonates and infant: 60 mg/kg/day in 3
divided doses
– Children: 30 mg/kg in 3 divided doses
• Reduce ICP: restrict fluid, hyperventilation
• Acute psychosis: Haloperidol 39

40. References
• Nelson Textbook of Pediatrics 20th edition
• Essential Pediatrics, OP Ghai, 8th Edition
• Harrisons textbook of Internal Medicine
• AAP Guidelines 2016
40

41. Thank You
41