Meningitis / Encephalitis
CC: Fever, headache, neck stiffness, AMS
PP: Photophobia, N/V, seizure, focal neuro deficit, rash, immunocompromised state
PN: No alternative toxic/metabolic cause, no focal infection source unless present
pertinent SHx: Sick contacts, travel, incarceration/dorm, IVDU, animal/tick exposure
Etiology:
Meningitis: bacterial/viral/fungal infection of meninges
Encephalitis: brain parenchymal inflammation, HSV important not to miss
risk factors: Age >50, immunocompromised, HIV, transplant, asplenia, recent neurosurgery, CSF leak
initial DATA: CBC, CMP, blood cultures x2, lactate if septic, CT head before LP if indicated, LP with CSF studies
pending DATA: CSF cell count/diff, glucose/protein, gram stain/culture, meningitis PCR, HSV PCR, cryptococcal Ag if immunocompromised
prior data:
MEDS: Anticoagulation, antibiotics, immunosuppression
COURSE:
Plan:
Neuro/ID consult
Droplet precautions until meningococcal disease excluded/treated
Blood cultures before antibiotics if possible
Do not delay antibiotics for CT/LP if unstable
Empiric antibiotics:
Vancomycin + Ceftriaxone 2 g IV q12h
Age >50/immunocompromised/pregnant: add Ampicillin for Listeria
Encephalitis concern: add Acyclovir 10 mg/kg IV q8h
Healthcare-associated/neurosurgery: Vancomycin + Cefepime/Meropenem
Dexamethasone before/with first antibiotics if bacterial meningitis suspected
LP unless contraindicated (CSF (cell count with diff, protien, glucose, gram stain,) serum glucose and blood culture )
CT head before LP if focal deficit, papilledema, seizure, severe AMS, immunocompromised, CNS lesion concer
Trend neuro checks, fever curve, renal function
Seizure precautions if encephalitis/seizure
Duration depends organism:
Meningococcus: ~7 days
Pneumococcus: ~10–14 days
Listeria/gram negative: ~21 days
HSV encephalitis: ~14–21 days