encephalitis Flashcards
what is encephalitis?
Encephalitis is a pathological condition characterised by inflammation of the brain parenchyma.
what viruses causes encephalitis?
HSV 1 - most common
HSV2, enterovirus, cytomegalovirus, EBV, VZV, HIV, flaviviruses
what bacteria causes encephalitis?
pathogens like those that cause meningitis, Lyme disease and Mycoplasma can cause meningoencephalitis.
Parasitic infections with malaria or toxoplasmosis should be considered, especially with recent travel or immunocompromise.
Autoimmune encephalitis, such as NMDA-receptor-antibody-associated encephalitis, should also be considered in the differential diagnosis
features of encephalitis?
primarily include altered mental status, more so than in meningitis.
Other suggestive features include:
Fever
Flu-like prodromal illness
Seizures
Focal neurological deficits
Headaches
Behavioural changes
Meningismus
ix for encephalitis?
A routine panel of blood tests including FBC, U+E, LFTs (as part of a septic screen)
Blood cultures and viral PCR
Cerebrospinal fluid (CSF) analysis with viral PCR
Consideration for malaria blood films in cases of exposure
Central Nervous System (CNS) imaging through CT and MRI can provide valuable insight. For instance, HSV typically affects the temporal lobes and bilateral multifocal haemorrhage is typical.
Other tests may include sputum cultures, throat swab, chest X-ray and EEG (particularly if presenting with seizures)
mx for encephalitis?
Management of suspected encephalitis is empirical and involves broad-spectrum antimicrobial cover with 2g IV ceftriaxone BD and 10 mg/kg aciclovir TDS. Once the causative organism is identified, targeted treatment may begin.
Supportive management of complications is also crucial and can include the termination of seizure activity using anticonvulsants.
Acute encephalitis is a notifiable disease and should be reported to the local health protection team.
