CNS infections Flashcards
_ limit access to CSF and brain tissue
capillaries
_ meningitis: normally associated with viral and fungal infections, adverse drug reactions, autoimmune disorders, cancer; essentially non bacterial cases; symptoms last longer than 2 weeks (variability)
Aseptic
_ : inflammation of the blood vessels
vasculitis
The leading cause of meningitis in Canada is _ (gram_) pneumonia we call it pneumococcal meningitis
streptococcus ; positive
If we see a rash present we know that the infection was caused by gram
_ bacteria due to the endotoxins such as meningococcal meningitis
negative
Fever, myalgia and rash are signs of what infection?
systemic infection
_ is seen as neck stiffness, Brudzinski’s sign, Kernig’s sign, jolt accentuation of headache
meningeal inflammation
Cerebral _ causes seizures
vasculitis
Clinical findings of headache, N&V, change in mental status, neurologic symptoms and seizures are indicative of _
elevated intracranial pressure
_: chills, neck stiffness, headache, altered mental state, focal neurological deficits, seizure, photophobia, N&V
meningitis
_: fever, nuchal rigidity, Brudzinski & Kernig signs, jolt accentuation of headache, GCS, rash
meningitis
What are expected glucose CSF glucose levels in patient with bacterial meningitis?
low CSF glucose levels (2.5 mmol/L or <40% of serum glucose)
Expected CSF protein level in patient with bacterial meningitis
High CSF protein levels (> 0.45 g/L)
What range would you expect the WBC to be at in a patient with bacterial meningitis
anywhere between 500-20000 WBC/mm3 and >80% neutrophils
In a patient who has viral meningitis you would expect to see _ CSF glucose levels
normal
_ to mildy _ CSF protein levels in a patient with viral meningitis
normal ; mildly; increased
What is the expected WBC range in a patient with viral meningitis?
10-1000 WBC/mm3
_ pneumoniae is gram _ ( bacterial pathogen of meningitis)
streptococcus ; positive
_ meningitidis is gram _ (bacterial pathogen of meningitis)
neisseria ; negative
80% of adult cases of meningitis are caused by _ and _
streptococcus pneumoniae ; neisseria meningitidis
_ monocytogenes are seen with eating, it gets in through the GI tract, only affects newborns, elderly, pregnant women
Listeria
Which bacterial pathogen only effects neonates?
Group B streptococcus
_ meningitis is responsible for ~50% of all cases of bacterial meningitis
pneumococcal
Infectious period of pneumococcal meningitis _ days prior to onset of clinical symptoms until pathogen is no longer present in _ and _ discharge (24 hours post targeted antibiotic therapy)
1-3 ; nasal ; oral
T/F: No droplet precautions necessary when treating a patient with streptococcus pneumonia
True
T/F: chemoprophylaxis is required for people in close contact with patient who has streptococcus pneumoniae
False
Neisseria meningitidis is gram _
negative
_ meningitis affects mainly children, adolescents and young adults
meningococcal
_ meningitis is responsible for about 25% of all cases of bacterial meningitis
meningococcal
~20% of people are colonized with _ in the nasopharynx
N. meningitidis
Chills, fever, weakness, generalized aches, petechial rash, _ shock and disseminated intravascular coagulation are signs and symptoms of _ meningitis due to the endotoxin production (gram_)
endotoxin ; meningococcal meningitis ; negative
The infectious period of _ meningitis: 7 days prior to onset of symptoms until pathogen no longer present in nasal or oral discharge (24 hours post targeted antibiotic therapy)
meningococcal meningitis
~20% of survivors of _ meningitis exhibit permanent neurological or physical deficit
Neisseria meningitidis
meningococcal meningitis = _ meningitidis
Neisseria
All suspected or possible cases of _ meningitis should be placed in droplet precautions for 24 hours post targeted antibiotic therapy
meningococcal meningitis
T/F: people who have come into close contact with someone with meningococcal meningitis need special attention
True
Vaccination recommended to control outbreaks, for patients with increased susceptibility to _ disease, and for travelers
meningococcal
Prior to 1986, _ was the leading cause of bacterial meningitis
Haemophilus influenzae
This type of infection is seen in people who choose not to vaccinate
Haemophilus influenzae
Suspected or possible cases of _ meningitis; droplet precautions 24 hours post targeted antibiotic therapy ``
Haemophilus influenzae
Haemophilus influenzae is gram _
negative ; rash is also seen in infected person
_ is transmitted by ingestion of contaminated foods (soft cheeses, refrigerated unpasteurized foods, deli meats) and poor hand hygiene
Listeriosis
_ is responsible for ~10% of all cases of meningitis; case fatality rate ~15%
Listeriosis
40-70% will transmit _ during surgery
GBS
What is the course of action if GBS was unable to be treated at the time of labour?
neonate blood cultures at 24 and 48 hours or antibiotic prophylaxis to prevent infection
Because bacterial meningitis is life threatening we need to administer _ (corticosteroid) with _ therapy
dexamethasone ; antibiotic
What are some supportive measures for treating a person with bacterial meningitis?
antipyretics, fluids and electrolytes, nutritional support
_ is responsible for ~85% of viral meningitis cases in Cananda
enteroviruses
_ is transmitted by direct contact nad fecal-oral route, most common in summer and fall
enteroviruses
Patients with bacterial meningitis require close monitoring after treatment is initiated for signs of _ and _
deterioration or complication
_: inflammatory process of the brain
encephalitis
_ may occur as an overlapping syndrome in a patient with encephalitis
meningoencephalitis
What is the most common type of encephalitis?
viral
What is the classic clinical triad of encephalitis?
- altered level of consciousness
- headache
- fever
What are 3 common neurological symptoms of a patient with encephalitis?
- disorientation
- focal neurologic deficits
- seizures
A patient’s lab values of: increased proteins, increased lymphocytes, normal glucose are all indicative of what?
viral encephalitis
_ is the most common cause of infection-related encephalitis (they have already been infected, latent, reactivation)
HSV
Focal temporal lobe symptoms are most common with viral encephalitis_; visual field cut, hemiparesis, aphasia
HSV
_ reduces overall mortality to 28% at 18 months post treatment of viral encephalitis -HSV
acyclovir
_: pus containing cavity surrounded by inflamed tissue in the brain
Focal intracerebral infection (brain abcess)
Clinical presentation of _ is nonspecific, largely based on location of _ within the brain and stage/progression of infection
brain abscess ; lesion
T/F: when someone has a brain abscess they have some predisposing infection elsewhere, it moved from that primary site, entered the bloodstream and travelled to the brain
True
_: antimicrobial therapy directed at suspected organisms
empiric therapy
With _ we are able to culture the brain abscess and see what antibiotics will work
aspiration
_ are warranted in cases of increased intracranial pressure or significant edema in a patient with a brain abscess
corticosteroids
What is the best type of drug to use for CNS infections that can easily cross the BBB?
Non-polar, lipid soluble drugs
When performing a lumbar puncture for the collection of CSF, how many tubes do you collect?
4; chemistry, microbiology, cytology
What is tube 1 of collected CSF used for?
cell count
What is tube 2 of collected CSF used for?
chemistry (glucose and protein)
What is tube 3 of collected CSF used for?
microbiology (gram stain and culture)
What is tube 4 of collected CSF used for?
cell count (or comparison to tube 1)
What is the first-line therapy for the treatment of suspected or culture proven gram - meningeal infections?
third generation cephalosporins
What is the gold standard for the definitive diagnosis of bacterial meningitis?
CSF culture
What type of plate would you put CSF specimen on for the diagnosis of bacterial meningitis?
blood agar and chocolate agar plate
What is the presumptive identification if there is growth on both CAP and BAP, and the gram stain is (-) diplococci?
Neisseria meningitidis
What is the presumptive identification if there is growth on both CAP and BAP, and the gram stain is (+) diplococci?
Streptococcus pneumoniae
What is the presumptive identification if there is only growth on the CAP, and the gram stain is (-) coccobacilli?
haemophilus influenzae
