Meningitis Flashcards
what are the features of meningism?
headache
stiff neck
photophobia
vomiting
what are the causes of meningism?
meningitis
SAH
infection accompanied by bacteraemia
severe viral infections i.e. influenza can also cause meningitism
what is characteristic of the neck stiffness in meningism?
stiffness on passive flexion (looking down to the feet)
what is neck stiffness with lateral or rotational movements indicate?
local cause in the cervical joints
by what mechanism does molecules pass through the blood brain barrier?
active transport
lipid solubility
what are the 5 steps of the pathogenesis of meningitis?
attachment to mucosal epithelial cells transgression of the mucosal barrier survival in the blood stream entry into CSF production of infection in the meninges with or without brain infection (encephalitis)
what are the bacterial causes of meningitis?
neisseseria meningitidis
streptococcus pneumoniae
e.coli
group B strep
what are the common organisms responsible for meningitis in neonates?
e.coli
group B streptococci
listeria monocytogenes
what are the viral causes of meningitis?
enteroviruses;
- cocksackie A and B
- polio
- echoviruses
- parechoviruses
mumps
HSV
what is aseptic meningitis?
non-infective meningitis
usually caused by tumour cells in the CSF which cause an elevated lymphocyte and protein count
no organism is cultures or detected
what cranial nerves palsies may occur with meningitis?
VI, VII, VIII
what are risk factors for meningitis?
recent skull trauma
alcoholism
diabetes
if the presentation of meningitis is acute and rapidly progressive what is the most likely cause?
meningococcal
what is Kernig’s sign?
with the hip flexed, the patient leg cannot be straightened due to hamstring spasm in meningism
if FBC shows a low white cell count (leucopenia) what does this indicate?
septicaemia or disseminated intravascular coagulation
= poor prognosis
(the infection should cause it to rise)