Encephalitis Flashcards
what is encephalitis
inflammation of the brain parenchyma associated with neurological dysfunction
what causes encephalitis
viral infections or bacterial in less common cases
main causative agents of encephalitis
Herpes Simplex Type 1 and 2
Varicella Zoster
BOTH ARE HERPES VIRUSES
risk factors for developing encephalitis
age below 1 or above 65
immunodeficiency
post infection
after a blood transfusion or transplantation
what are the presenting symptoms of encephalitis
fever, confusion, rash, altered mental state, cough, GI infections, seizures, vomitting, headache, drowsiness, focal neurological symptoms
can encephalitis present with meningismus
yes. it can present with a headache, neck stiffness and photophobia
onset of encephalitis
usually its mild cases and onset is subacute (hours to days)
signs of encephalitis on physical examination
reduced consciousness, photophobia, neck stiffness and decreasing GCS, seizures and pyrexia (fever)
signs of ICP raised will also be seen
what are signs of raised inter cranial pressure
papilloedema
cushings response in response to raised ICP
triad of cushings response seen on physical examination
in response to raised ICP;
hypertension, bradycardia and irregular breathing
what investigations will be done for encephalitis
bloods (FBC, LFTs, electrolytes and urea, glucose, viral serology and ABG)
FBC will show high WCC
other investigations
blood cultures, CT and MRI brain
MRI/CT:
Exclude mass lesion
HSV causes oedema of the temporal lobe on MRI
Lumbar Puncture:
High lymphocytes
High monocytes
High protein
Glucose is usually normal
Viral PCR
CSF analysis
EEG - may show epileptiform activity due to presence of seizures in encephalitis
what is the first line treatment of encephalitis
usually caused by a viral infection so will be treated with antivirals
ACYCLOVIR
plus SUPPORTIVE CARE
what is supportive care in context to encephalitis treatment
Supportive care may include endotracheal intubation and mechanical ventilation, circulatory and electrolyte support, prevention and management of secondary bacterial infections, deep venous thrombosis prophylaxis, and gastrointestinal (ulcer) prophylaxis.
prognosis of encephalitis
mortality and morbidity usually depend on the underlying aetiology.