What is meningitis?
Inflammation of the leptomeninges and underlying subarachnoid CSF
What ages are more predisposed to meningitis?
Infants, young children and the elderly
What is the underlying cause of most cases of meningitis?
An infectious agent that has colonised or established a localised infection elsewhere in the host and spread to the CNS
What sites of infections are commonly associated with meningitis?
How can an infectious organism at a distant site cause meningitis?
By circumventing the hosts defense and gaining access to the CNS
How might bacteria gain access to the CNS to cause meningeal disease?
In what conditions might organisms directly spread to cause meningeal disease?
What can often worsen the problem in meningitis?
The immune response
How can the immune response worsen meningitis?
Creates leaky blood vessels, allowing fluid and WBC to enter meninges and cause swelling
What is the result of swelling in meningitis?
Decreased blood flow to the brain
What can cause inflammation of the meninges?
What is the more common form of meningitis?
Viral
What is the more serious form of meningitis?
Bacterial
Due to the severity of bacterial meningitis, what should happen to all patients?
Treat as bacterial meningitis until proven otherwise
What viruses can cause meningitis?
What are the most common bacterial causes of meningitis in neonates?
What are the most common bacterial causes of meningitis in infants?
What group of infants are at risk of H. influenza B meningitis?
Those who are unvaccinated
What are the most common bacterial causes of meningitis in adults?
What are the most common bacterial causes of meningitis in the elderly and immunocompromised?
What are the non-infective causes of meningitis?
What are the risk factors for meningitis?
What are the possible presenting features of meningitis?
What are the signs of shock?