Neurological Infections Flashcards
define meningitis
an inflammation of the meninges
common causes of bacterial meningitis
streptococcus pneumoniae
neisseria meningitidis
haemophilus influenzae
listeria monocytogenes
common causes of viral meningitis
echoviruses
coxsackie A + B
poliovirus
common causes on non-infective meningitis
malignancy chemical drugs (NSAID + trimethoprim) sarcoidosis SLE
clinical features of meningitis
headache
neck stiffness + pain
photophobia
nausea + vomiting
common signs of meningitis
fever
reduced levels of consciousness
non-blanching petechial rash
Kernig’s sign (hamstring spasm when attempting to straighten leg)
investigations of meningitis
bloods (FBC, U+Es, clotting + glucose) ABG blood cultures CT head lumbar puncture
acute management of meningitis
primary care: IM benzylpenicilin and hospital referral
secondary care: IV ceftriaxone (bacterial) or IV aciclovir (viral)
CSF results of bacterial meningitis
clear or turbid fluid polymorph predominance 90-1000+ cell count culture +ve raised protein (over 1.5g/L) low glucose (CSF less than half of plasma glucose)
CSF results of viral meningitis
clear fluid
raised protein count
normal glucose
high WCC (lymphocytes)
common cause of meningitis in neonates
group B streptococcus
treatment provided to reduce risk of long-term neurological symptoms in bacterial meningitis
IV dexamethasone - given within 4hrs of IV antibiotics to reduce risk of hearing loss and neurological sequelae
management of viral meningitis
supportive + symptomatic care
e.g. analgesia, antipyretics, nutritional support and hydration
contraindications for lumbar puncture in meningitis
signs of raised intracranial pressure
define encephalitis
an inflammation of the brain parenchyma (encephalon)
causes of encephalitis
primarily viral
e.g. Herpes Simplex Virus Type 1 (most common), HSV-2, EBV or VZV
clinical features of encephalitis
altered mental status
fever
prodromal viral symptoms
early seizures
investigations of encephalitis
bloods (FBC, U+Es, CRP/ESR, clotting + cultures)
viral PCR
lumbar puncture
MRI
common findings of encephalitis on neuroimaging
bilateral multifocal haemorrhage within temporal lobes
management of encephalitis
IV ceftriaxone and aciclovir for 2wks
if seizures: anticonvulsants (e.g. phenytoin)
common side effects of aciclovir
generalised fatigue/malaise
GI disturbance
photosensitivity
urticarial rash
causes of encephalopathy
hypoglycaemia
hepatic encephalopathy
DKA
drug-induced
common findings in CSF for viral encephalitis
lymphocyte composition
low glucose
raised protein
