CNS infections - meningitis Flashcards
What are the most common causes of bacterial meningitis?
18-60 year olds = staphylococcus pneumonia or neisseria meningitis
<18 year olds = haemophilia influenzae
neonates = group B streptococcus
elderly and infants = listeria monocytogenes
What is the most common cause of meningitis?
viral related illness
What are the most common bacterial causes of meningitis?
for 18-60 year olds - staphylococcus pneumoniae and neisseria meningitis
<18 years - haemophilia influenzae
neonates - group B streptococcus
elderly and infants - listeria monocytopgenes
What is the most common viral cause of meningitis?
enterovirus
What are the non-infectious causes of meningitis?
migraine
SAH
vasculitis
What are the key differentiating symptoms of meningitis?
neckstiffness
rash - non-blanching
vomiting, headache, fever
What investigation is carried out to diagnose meningitis?
viral PCR testing on a CSF sample
What are the 2 specific tests used to test for meningitis?
Kernig’s test - lie on back, flex hip and knee to 90 degrees, slowly straighten knee, painful in meningitis
Brudzinski’s test - lie on back, lift head and neck off bed. if hips and knees flex involuntary = meningitis
How do you tell the difference between a bacterial and viral cause of meningitis based of the CSF?
bacteria make if go cloudy, increase protein count, decrease glucose content, and increase neutrophil count
viral causes leave the CSF clear, protein and glucose content remains normal, but there is an increase in lymphocyte count
What antibiotic is used to treat bacterial meningitis where the causative organism has not been identified?
ceftiaxone
What antibiotic is used as post exposure prophylaxis?
ciprofloxacin
What is the key potential complication of meningitis?
hearing loss
