Meningitis Flashcards
What is meningitis?
Inflammation of the leptomeninges
What are the leptomeninges?
Pia mater and Arachnoid together
What are the pathogens that commonly cause meningitis? Which population does each specifically affect?
Group B Streptococci, E. coli and Listeria monocytogenes
- Neonates
N meningitidis
- Children and teens
Streptococcus pneuomniae
- Adults and elderly
H. influenzae
- Nonvaccinated infants
Coxsackievirus
- Children; fecal-oral transmission
Fungi
- Immunocompromised patients
What is the classic triad presentation of meningitis?
Headache
Nuchal rigidity
Fever
What are the none triad symptoms of mengitis?
Photophobia (virus related)
Vomiting
Altered mental status
How is meningitis diagnosed?
Lumbar puncture
At what vertebral level is a lumbar puncture performed? Why?
Between L4 and L5 (level of iliac crest)
Spinal cord ends at L2 so this ensures we do not puncture the spinal cord
What layers are pierced when performing a lumbar puncture?
Skin
Ligament
Epidural space
Dura
Arachnoid
Pia not crossed by spinal cord ends at L2!
What is found in the CSF of bacterial meningitis?
Neutrophils with decreased glucose because bacteria consumes the glucose
Gram stain and culture often identify the causative organism
What is found in the CSF of viral meningitis?
Lymphocytes with normal glucose
What is found in the CSF of fungal meningitis?
Lymphocytes with decresaed glucose
Glucose decreased because it is consumed by the fungi
What complications are usually seen with bacterial meningitis?
Death
- herniation secondary to cerebral edema
Hydorcephalus, hearing loss and seizures
- sequelae related to fibrosis
