Encephalitis Flashcards
What is the most common cause of infective encephalitis?
HSV (1 is more common than 2)
What are some major symptoms of encephalitis?
Fever, headache, stiff neck, altered mental status
Encephalitis in the brainstem may lead to what symptoms?
Autonomic dysfunction, myoclonus and cranial neuropathies
Encephalitis in the flavivirus may lead to what symptoms?
Tremor or movement disorders
How does the HSV virus lead to infective encephalitis?
The virus migrates through to the trigeminal ganglia or the olfactory bulb, the virus then replicates again and stays latent and then reactivated
When should treatment for suspected infective encephalitis be started?
As soon as there is a suspicion
How would infective encephalitis show in a lumbar puncture?
Raised white blood cell count
How would infective encephalitis show in imaging?
High signal change and T2 hyper intense lesions in the frontal temporal regions
What is the role of the drug Acyclovir?
An antiviral medication to prevent the spread of the herpes virus
What is paraneoplastic encephalitis?
Relates to a systemic cancer
How does systemic cancer lead to intracellular encephalitis?
Antibodies are made due to the cancer which target nerve cells in the CNS, leads to the activation of T cells with neuronal loss
How does systemic cancer lead to extracellular encephalitis?
Antibodies interfere with normal functioning, neurones can’t transmit signals to each other and leads to a neurological syndrome
What are the symptoms associated with limbic encephalitis?
Irritability, depression, sleep disturbances, seizures, hallucinations and short term memory loss
What are the four criteria for diagnosing limbic encephalitis?
- sub-acute onset
- bilateral brain abnormalities
- high white blood cell count or epileptic activity on EEG
- reasonable exclusion of other causes
What is the main proteins causing limbic encephalitis?
LGI-1 and NMDA
What is the role of LGI-1?
Bridges ADAM22 and ADAM23 molecules
How does LGI-1 cause limbic encephalitis?
Antibodies attach to the receptor and stop the connection and communication of the molecules
What symptom is associated with LGI-1 distruption?
Faciobrachial dystonic seizures
What would CSF, EEG and MR show for disruption of LGI-1?
Normal CSF, abnormal EEG and abnormal MR
How does NMDA cause limbic encephalitis?
Antibodies attach to the NMDA receptor, receptors then crosslink and are removed from the postsynaptic membrane due to mitosis and stops normal signalling between the pre and post synaptic neuron
What symptoms are associated with NMDA disconnection?
Flu symptoms, psychiatric symptoms, movement disorders and seizures
What would CSF, EEG and MR show when NMDA receptors are disconnected?
CSF normal, EEG generalised or focal seizure activity, MR normal
What is the first line pharmacological drug for autoimmune encephalitis?
Corticoidsteroids
What is the role of corticoid steroids?
Bind to glucocorticoid receptors and promote anti-inflammatory genes and decrease inflammatory response genes
What are the other three non-pharmacological first line treatments for autoimmune encephalitis?
Intravenus immunoglobin
Plasma exchange
Tumour treatment/removal
