CNS Infection Falkenberg Flashcards
What are some ways you can get CNS infections?
bacteria viruses fungus parasites others, lyme disease, syphilis
What is a common route of CNS infection?
hematogenous/venous spread
What kind of route of infection is this; abcess, respiratory, GI/GU, pericranial sites-sinuses, middle ear?
heamtogenous/venous spread
What are 2 less common routes of CNS infection?
penetrating trauma and entry through congenital defects
What are the three types of CNS infection?
meningitis
encephalitis
myelitis
What is meningitis?
infection of meninges ESPECIALLY arachnoid
What is encephalitis?
infection of the brain
What is myelitis?
infection of spinal cord
T/F
THe brain and spinal cord repair well
F, they do not repair well
Brain is (enclosed/closed)
enclosed
Since the brain is enclosed what does this mean for clinical purposes?
it means that increased cranial pressure can lead to brain herniation and necrosis!!! OH NO!
What can CNS infections ultimately lead to?
sepsis! :(
What are the signs and symptoms of acute bacterial meningitis?
Similar to migraines
i.e. headache, nausea, vomiting, fever, meningismus, altered consciousness
In children you dont want to miss acute bacterial meningitis, what should clue you in to check to see if the child has it?
If child is less than 28 days old and has a fever greater than 100.6 then you should give full septic work-up and lumbar puncture
What are causes of acute bacterial meningitis?
S. pneumonia H. Influenze L. monocytogenes Group B steptococcus N. meningitidis
How do you rule out a space occupying lesion?
CT of head
What are some tools to diagnose bacterial meningitis?
lumbar punctures
CT
blood cultures
What will a gram stain tell you?
will tell you if you have bacteria :)
What are normal values of CSF?
5-20 pressure .18-.45 protein 2.5-3.5 glucose normal gram stain .6 glucose to CSF ratio less than three WCC
What is the treatment for acute meningitis?
antibiotics
hospitalization
steroids
supportive care
What are the symptoms of viral meningitis?
headache
fever
viral syndrome
meningismus (sore and stuff without actual inflammation and infection)
What are causes of viral meningitis?
enteroviruses
echovirus, coxsackie A and B
If you have monocytes in your CSF and normal gram stain and glucose what do you have?
viral meningitis
If you have monocytes and a fibrin web in your CSF what do you have?
fungal menigitis/TB
What is the treatment for viral menigitis?
supportive care
antivirals
T/F most cases of viral meningitis resolve after 7-10 days
T
What are the signs and symptoms of encephalitis?
confusion PERSONALITY CHANGE altered mental status fever seizures
What are causes for encephalitis?
herpes simplex virus
varicella zoster virus
HIV
rabies virus
How do diagnose encephalitis?
H and P CT lumbar puncture CSF antibody titers PCR of CSF for herpes encephalitis brain biopsy (in exceptional cases)
What are the signs and symptms of brain abscesses?
headache focal neurologic deficits fever, chills papilledema (w. increased ICP) nausea, vomiting (w. increased ICP)
T/F
you will see other signs of infection besides fever and chills in brain abscesses
F you will not, you will only see fever and chills and that is even rare
(this makes it difficult to diagnose)
What is the treatment for brain abscesses?
antibiotics
surgical drainage
What are common causes of brain abscesses?
streptococcus viridans
staphylococcus aureus
When should you get a lumbar puncture?
suspected cases of meningitis and encephalitis
What can you use if you are suspicious someone has severe headaches, MS, or subarachnoid hemorrhage?
lumbar puncture
T/F
lumbar puncture can be used as a treatment
T for pseudotumor cerebri and increased ICP
Why dont you want to use a quinke for a spinal tap?
because they give people headaches :(
cuts the dura which makes CSF leak out
How do you give a spinal tap?
tell patient mark site sterilize betadine drape local anesthetic (lidocaine) (use a good needle, like the gertie, sprotte, whitacre) introducer needle spinal needle feel "pop" of dura measure pressure (fill tubes)
Where do you give lumbar puncture?
L2/L3
If you cant find the correct spot with a needle what do you do?
pull all the way out and try again, put it in straight DO NOT BEND NEEDLES THEY CAN SNAP IN PEOPLE
What are some complications of a lumbar puncture?
spinal headache (PDPH) nerve damage- rare back pain infection - rare bleeding -rare
How much CSF should you take out?
minimal possible (usually around like 1-2 CC) 10 at MAX!
What are contraindications for spinal tap?
patient refusal
skin infections or abscess (dont want to spread infection into the CSF)
bleeding disorder
space occupying/ mass lesion
Why dont you want to do a lumbar puncture with a space occupying or mass lesion?
You mess up fluid equilization and increase pressure cranially while decreasing pressure caudally.
How do you fix a Dura leak that was caused by a messed up spinal tap?
blood patch (take epidural of blood and put the blood over the dural opening to make a patch)
