encephalitis in childhood class/3-8-99... · 2020. 10. 24. · acute encephalitis mostly due to...
TRANSCRIPT
Encephalitis
in childhood
Pegah Katibeh
Pediatric Neurologist
Shiraz University of Medical Sciences
A 7-year-old male
Headache, stupor, tendency to sleep, fever, unaware to recognise the time
and the place...
Acute Encephalitis
The inflammation of the parenchyma of the brain especially that of the cerebral
cortex
The inflammation of the CNS
Encephalitis… the parenchyma...mostly due to viral infections
Meningitis… the meninges... mostly due to bacterial infections
Symptoms
Fever
Headache
Mental changes
Confusion
Hallucinations
Personality changes
Diplopia
Fatigue
Tremors
Rash
Loss of consciousness
Acute Encephalitis
Mostly due to viral inf.
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)
HSV-1
The most common etiology of acute sporadic
encephalitis
HSV-1
acquired in childhood period,
re-activates after years
HSV-1
• Primary infection;
• On the mucosa of oropharynx, mostly asymptomatic
• fever, pain, dysphagia
• 2-3 weeks
Following primary infection, a
latent infection in trigeminal
ganglion
HSV-1
Inferior and medial temporal lobe
Orbito-frontal lobe
Limbic structures
Inflammation
necrotizing lesions
Hemorrhagic necrosis in herpes encephalitis
especially when remains untreated.
Widespread edema and
subarachnoid hemorrhage
areas in medial temporal
and orbitofrontal regions
HSV-1
HSV-1
Fever
Unilateral or generalized headache
Mental changes
Focal seizures
Focal neurological deficits
Dysphasia
Hemiparesis
VZV
Primary infection… chickenpox
Latent infection thereafter
The commonest reactivation… herpes labialis
Chickenpox, herpes labialis and zona may be complicated with encephalitis
Epstein Barr Virus
Causes infectious mononucleosis
May cause encephalitis
Direct invasion of CNS or immune mechanisms
Cortex, brain stem, basal ganglia, temporal lobe
CMV
Encephalitis in both immunocompetent and immunosuppressed
Risk is higher
immunosuppressed,
organ transplanted
HIV-infected patients
Organ transplantation, highest risk… CMV (-) donor to CMV (+) recipient
HIV
In 10-50% of AIDS patients, HIV infection in CNS
Multinuclear giant cells in gray matter and central white matter are
pathognomonic.
Rabies
Lyssavirus
Acute progresive fatal encephalitis.
Transmitted with infected saliva of the animal
Incubation period: 5 days-6 mo.(20-60 days)
III, IV and IXth canial nerve palsies
Prodromal period, neurological disease period, paralysis,
coma, and death.
Mumps
The commonest complication; inflammation in CNS
A pleocytosis in CSF in half of the cases
In 5-30%: headache, vomiting, neck stiffnes
Clinical Evaluation
History
PE
Neck stiffness
CBC
Biochemistry
Culture
Imaging
Serology
CSF analysis
History
Season
Localisation
Travel
Occupational exposure
Exposure to animals
Immunization
Immune status of the patient
UNC-93B
Lab
CBC
Renal and hepatic tests
Coagulation studies
Plain chest X-ray
Nonspecific
• CSF analysis
• Cranial imaging
Main diagnostic
methods
Cranial Imaging
MRI
• Sensitive for early
period HSV
encephalitis
• Edema in
orbitofrontal and
temporal regions
CT Less sensitive than MRI
Herpes simplex encepalitis CT(A) and MRI (B-F) temporal lobe
involvement
CSF Analysis
Cell count: 10-2000 cells/mm3
Mostly <500 cell/mm3
Lymphocyte predominance
Erythrocytes (in 80% of the cases)
Normal CSF findings in 10%
Glucose (mg/dl): normal or low
CSF glucose/serum glucose: normal (>0.6) or low
Protein (mg/dl): >50
Gram staining: no microorganisms
Culture: none
Microbiology
HSV PCR: For the first 24-48 hours, detecting HSV DNA by PCR in CSF:
specific (100%) and
sensitive (75-98%)
Herpes simplex encephalitis; Neurons including Cowdry A type intranuclear
inclusion bodies. Hematoxylen-Eosin, X400.
Treatment
If shock/hypotension exists, crystaloid infusion
If unconscious, provide airway/breathing
Seizure, lorazepam 0.1 mg/kg, IV
Treatment
For encephalitis, give acyclovir
Treatment
Acyclovir IV, 14 – 21 days
HSV encephalitis
VZV encephalitis
Some keys
Atypical lymphocytes on peripheral
smear… IMN
High amylase … Mumps
Complications
Acute period
Seizure
Inappropriate ADH synd.
Intracranial pressure inc.
Resp. arrest
Coma
Death
Chronic period
Chronic fatigue
Depression
Personality changes
Gait disorders
Memory disorders
Speech disorders
Visual problems
Mental retardation
Hemiplegia
Seizure
Prognosis
The virulence of the virus
Patient’s;
previous health status
immune status (chemotherapy, transplantation, AIDS)
age(<1, and >55 years)
any neurological symptoms
Prognosis
Being in coma on prsentation: severe inflammation
in the brain, poor prognosis
Treated
Mortality… 20%
Morbidity… 40%
Untreated
Mortality … 50-75%
Morbidity… 100%
Autoimmune encephalitis
In children, acute encephalopathy might develop several weeks after
infection or vaccination and is then most likely an autoimmune reaction.
Well known autoimmune encephalopathies in children include ADEM and
AHLE.
Recently, antibody mediated autoimmunity in CNS have been described in
an increasing number of children with encephalitis of unknown etiology
ADEM
Brain Abscess
Focal collection in the brain parenchyma due to
Infection
Trauma
Surgery
Pathogenesis
Hematogenous: multiple abscess
Chronic pulmonary inf. (lung abscess, empyema…)
Skin inf.
Pelvic inf.
Intraabdominal inf.
Bacterial endocarditis
Cyanotic congenital heart dis.
• Direct transmission
– Subacute or chronic otitis media, mastoiditis (inferior temporal lobe and
cerebellum)
– Frontal or ethmoid sinusitis (frontal lobes)
– Dental infections (frontal lobes)
Early lesion (first 1-2 weeks):
The borders are not clearly defined, localised edema
Inflammation, no necrosis
“Cerebritis”
After 2-3 weeks, necrosis
A fibrous capsule
Etiology
Aerobs+Anaerobs
Signs&Symptoms
Headache
Fever Neck stiffness
Mental changes
Nausea, vomiting
Warning
LP is contraindicated!
Diagnosis
Imaging
MRI CT
Treatment
• Intervention
• Antibiotics
– Ceftriaxone + metronidazole
Mortality 0-30 %
www.rochester.edu
Thanks for your attention
Any questions?