NS Infection - Brain Abscess/Empyema & HIV Flashcards
1
Q
Difference between brain abscess and empyema?
A
Abscess if localised pus in the brain
Empyema is usually a thin layer of pus between dura & Arachnoid
2
Q
How does a brain abscess/empyema present?
A
- Fever
- Headache
- Focal Signs e.g. seizures or dysphasia or weakness
- Raised ICP (Papilloedema, depressed consciousness)
- ~Meningism with empyema
- Underlying source infection (Dental, ear, sinus)
3
Q
Whats the DDX for a brain abscess?
A
Any other focal lesion e.g. tumour or subdural haematoma
4
Q
Causes of Brain abscess/empyema?
A
- Adjacent infection (Dental, Ear, Sinus)
- Blood born infection (e.g. endocarditis)
- Neurosurgical procedures
- Penetrating head injury
5
Q
How do we approach a suspected brain abscess or empyema?
A
- CT/MRI
- Investigate any source infection
- Blood culture
- Biopsy (Drainage) for culture & Sensitivity tests
6
Q
Describe the bacteria in a brain abscess
A
Often mixtures of organisms
- Streptococci, mainly Strep Milleri group (E.g. Strep Constellatus)
- Anaerobes such as bacteroides
7
Q
We’ve investigated our brain abscess, our do we treat it?
A
- Surgical drainage if possible
Multiple High Dose Abx:
- Penicillin or Ceftriaxone for Streptococci
- Metronidazole for Anaerobes
8
Q
Patient’s with HIV can present with a lot of unusual Nervous conditions such as?
A
- Cerebral Toxoplasmosis
- Aseptic Meningitis/Encephalitis
- Cerebral Lymphoma
- Cerebral Abscess
- Cryptococcal Meningitis
- Dementia
- Leucoencephalopathy
9
Q
How would we investigate a patient with CNS manifestations we suspect to be HIV related?
A
- India Ink for cryptococcal Antigen
- Toxoplasmosis Serology (IgG)
- PCR for JC virus, CMV & HIV
10
Q
What brain infections are likely in HIV patients with a low CD4 count?
A
- Cryptococcus neoformans
- Toxoplasma gondii
- Progressive multifocal leukoencephalopathy (PML)
- Cytomegalovirus (CMV)
- HIV-encephalopathy (HIV-associated dementia)
