Encephalitis **** Flashcards
What is it?
Inflammation of the brain
Causes:
What are the 2 main viral causes?
What is Japanese B encephalitis?
Herpes simplex virus (HSV)
Varicella Zoster Virus (VZV)
Japanese encephalitis is a viral brain infection that’s spread through mosquito bites. It’s most common in rural areas in southeast Asia, the Pacific islands and the Far East, but is very rare in travellers.
Other:
EBV CMV HIV Measles Mumps Malaria
Causes:
Autoimmune:
- What part of the brain is typically affected?
What other bacterial infection of the CNS may cause encephalitis?
Other causes?
Medial temporal lobes
Meningitis - leads to meningoencephalitis
Idiopathic Spirochetes - listeria, Lyme, syphilis TB Protozoa - malaria Fungal - aspergillus
S+S:
How do the symptoms initially start?
Neuro symptoms?
Non-specific so..:
- fever
- headache
- nausea
- vomiting
- malaise
Seizures
Odd behaviour or confusion
Low GCS
Focal signs - also known as focal neurological deficits or focal CNS signs are impairments of nerve, spinal cord, or brain function that affects a specific region of the body, e.g. weakness in the left arm, the right leg, paresis, or plegia.
Investigations:
What 2 things do you need to remember to ask about in the history?
Travel history - malaria
Bite exposure - lyme disease - tics
Investigations:
Bloods:
- What needs to be done as part of sepsis 6?
- What can be done to test for viruses?
- You can also use a blood film to look for other pathogens. What may you find on the film?
Blood culture
Viral PCR
Toxoplasma IgM film
Malaria film
Investigations:
What imaging is done?
What does temporal lobe inflammation suggest? - 2
What does meningeal inflammation suggest?
CT contrast - MRI is alergic to contrast
HSV or autoimmune disease
Meningoencephalitis
Investigations:
Special tests - LP:
- What does raised lymphocytes suggest? - 2
- Polymorphonuclear leukocytes, or PMNs, are a special family of white blood cells. What does their presence in the CSF suggest?
- What does low glucose suggest?
- How may the pathogens of all kinds be identified?
Viral/autoimmune cause
Bacterial cause
Bacterial cause
Viral PCR and gram stain
Management:
What drug is given STAT to cover HSV before it is confirmed?
How long should it be continued for if it is confirmed?
What other drug is used for those with CMV who are immunosuppressed?
What drug is given for autoimmune encephalitis?
Who should be notified if infectious?
Aciclovir IV STAT
14-21 days
Ganciclovir
Immunosuppression - steroids, IVIg, plasma exchange
Public health
Complications:
Short term - 3
Long term
Seizures
Raised ICP
SIADH - Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by excessive unsuppressible release of antidiuretic hormone (ADH) either from the posterior pituitary gland, or an abnormal non-pituitary source.
——
Neurological complications, including motor and cognitive problems
Brain (Cerebral) abscess:
What is it?
How is it different from encephalitis?
Source of pathogens:
- What may cause direct infection? - 2
- Contiguous spread from neighbouring infections. Where can the infection originate from? - 3
- What infection may be carried in the blood?
A focal infection of brain tissue
Penetrating trauma
Neurosurgery
Mastoiditis
Sinusitis
Dental infection
Endocarditis
IVDU
Brain (Cerebral) abscess:
The classic triad of symptoms
Other symptoms
What is important to ask about in history?
Headache
Fever
Focal neurology
Vomiting
Confusion
Lethargy
Seizures
Any recent infections in the head and neck region?
Brain (Cerebral) abscess:
Investigations - Imaging:
What would you see on CT/MRI head with contrast?
Why should an LP be avoided?
What can also be done for culture?
Ring-enhancement of a pocket of pus
Brain herniation
Image-guided needle aspiration
Brain (Cerebral) abscess:
Management:
What 2 antibiotics can be given?
What is done if antibiotics aren’t sufficient?
Ceftriaxone + metronidazole IV for 6-8 wks
Aspiration or surgical drainage if >2mm
