MENINGITIS Flashcards
What are the different ways that infective agents reach the meninges resulting in meningitis?
Haematogenous (most common)
Direct - sinuses or inner ear
Fractures of skull
What are the most common bacterial agents that causes meningitis?
Haemophilus influenzae
Neisseria meningitidis - gram negative diplococci
Streptococcus Pneumoniae - gram positive pairs/short chains
What is are the triad of clinical features associated with meningitis?
Headache
Photophobia
Neck stiffness
What are the two signs that are used to look for neck stiffness in someone with suspected meningitis?
Kernig’s sign
Brudzinski’s sign
How do you test for Kernig’s sign?
Extend knee with hip flexed at 90˚
How do you test for Brudzinski’s sign?
With patient supine, the neck is flexed passively. You are looking for involuntary lifting of the legs.
What symptoms might be seen in someone with suspected meningitis where there is raised intracranial pressure?
Confusion
Fluctuating levels of consciousness
Seizures
Cranial nerve palsies
What additional symptom may be seen in a patient who is suspected of having meningococcal septicaemia?
Rapidly progressing petechial/purpuric non-blanching rash
What are the major causes of aseptic meningitis?
Viruses
What is the leading causes of viral meningitis?
Enteroviruses - including echoviruses and coxsackieviruses.
What organism is most likely to be responsible for a chronic meningitis, developing over weeks to months?
Tuberculosis
What is the organism associated with meningitis is those with advanced HIV?
Cryptococcal meningitis (fungal)
What is the main investigations that should be done with someone who has suspected meningitis?
LP
When should a CT be done before a lumbar puncture?
Immunocompromised patients
Those with a history of central neurological disease
Those with new-onset seizures
Those with papilloedema
Those with abnormal levels of consciousness
Those with a focal neurological deficit
Why is important to do a CT on a patient with suspected meningitis if they have symptoms associated with raised intracranial pressure?
To assess the risk of coning
Give a description of the appearance of the CSF in each of the following situations: Normal Bacterial meningitis Viral meningitis Tuberculous meningitis
Normal - clear
Bacterial - Turbid/pus
Viral - clear/turbid
Tuberculous - Turbid/viscous
What are the levels of neutrophils in the CSF in each of the following situations: Normal Bacterial meningitis Viral meningitis Tuberculous meningitis
Normal - none
Bacterial - 200-10,000/mm3
Viral - none
Tuberculous - 0-200/mm3
What are the levels of lymphocytes in the CSF in each of the following situations: Normal Bacterial meningitis Viral meningitis Tuberculous meningitis
Normal -
What are the levels of protein in the CSF in each of the following situations: Normal Bacterial meningitis Viral meningitis Tuberculous meningitis
Normal - 0.2-0.4g/L
Bacterial - 0.5-2.0g/L
Viral - 0.4-0.8g/L
Tuberculous - 0.5-3.0g/L
What are the levels of glucose in the CSF in each of the following situations: Normal Bacterial meningitis Viral meningitis Tuberculous meningitis
Normal - >1/2 blood glucose
Bacterial -
What are the normal pressures of the CSF?
10 to 18 mmHg
What are the complications associated with meningitis?
Hydrocephalus Cerebral oedema Venous sinus thrombosis Subdural empyema Cerebral abscess Arteritis
What is the treatment of bacterial meningitis?
Treatment should be started immediately after LP, unless there is going to be a 30 minute delay prior to LP.
Cefotaxime or ceftriaxone
Cover with ampicillin with or without gentamicin where Listeria is suspected.
When should steroids be used in the treatment of meningitis?
In all adults with suspected or proven pneumococcal meningitis.
In tuberculous meningitis
Must be given within 12 hours of start of antibiotics
