Meningitis Flashcards
What is meningitis?
Inflammation of the subarachnoid space
What are the two main types of meningitis?
Which one is more common?
Which one is more serious?
Bacterial meningitis and Viral meningitis.
Viral meningitis is more common.
Bacterial meningitis is more serious.
What are main causes of viral meningitis?
- Enteroviruses
- Influenza virus
- Human Simplex Virus 2
What are the common causes of bacterial meningitis?
What are some rare causes of bacterial meningitis?
Common causes
- Streptococcus pneumoniae
- Neisseria meningitidis
Rare causes
- Haemophilus influenzae
- Mycobacterium tuberculosis
What are some non-pathogenic causes of meningitis?
Drugs, trauma, neurosurgery, cancer
What are symptoms of meningitis?
Meningal inflammation:
- Headache
- Photophobia (sensitivity to light)
- neck stiffness
- drowsiness
Systemic symptoms:
- Fever
- drowsiness
- lethargy
Where does the infection start?
Bacterial or viral colonisation of the nasopharynx and oropharnyx. Disease onset only when pathogen enters the subarachnoid space.
What can be used to diagnose meningitis?
- Cerebrospinal fluid sample from a lumbar puncture
- blood cultures and sample for PCR test
- throat swab
What would the expected findings be in a cerebrospinal fluid sample of a bacterial meningitis patient?
- Decreased glucose levels
- Increased white blood cell count (mainly neutrophils)
- increased protein count.
-ve gram stain = Neisseria meningitidis
+ve gram stain = Streptococcus pneumoniae
What would the expected findings be in a cerebrospinal fluid sample of a viral meningitis patient?
- Normal glucose levels
- increased or normal protein count
- increased white blood cells (mainly lymphocytes)
- no gram-stain, no cultures
What is the treatment for bacterial meningitis?
- IV antibiotics (Penicillin) as soon as possible
- Investigations into cause
- Pain relief
- Fluids
What is the treatment for viral meningitis?
- Reassurance
- Pain relief
- Can usually be recovered from at home
