Meningitis Flashcards
Inflammation of the coverings of the brain(meninges)
Meningitis
(1) Definition of Meningitis: Inflammation of the coverings of the brain(meninges)
(2) Meninges consist of the dura mater, arachnoid mater, pia mater
(3) Unlike the brain the meninges have nociceptors
(4) May be viral or bacterial, spirochete or fungal etiology
(5) One of the 10 most common infectious causes of death
(6) Fatality rate 25% with 28% of survivors having permanent neurologic morbidity
Overview of Meningitis
(1) Streptococcus pneumonia
(2) Neisseria meningitides
(3) Listeria monocytogenes
Common bacterial etiologies: Meningitis
(1) Enterovirus
(2) Herpes simplex virus
(a) Between 13-36% of patients presenting with primary genital herpes may have
findings consistent with meningeal involvement.
1) Headache, photophobia, meningismus
(3) West Nile Virus
Common viral etiologies: Meningitis
(1) Classic triad of acute bacterial meningitis
(a) Fever
(b) Nuchal rigidity
(c) Change in mental status
(2) Nuchal rigidity due to meningeal irritation
(3) Other symptoms
(a) Headache
(b) Photophobia
(c) Rash (associated with Neisseria meninitidis)
Signs and symptoms of meningitis
(a) Important distinguishing feature is degree of brain function disturbance
(b) In meningitis cerebral function usually remains normal
(c) Encephalitis brain function is more abnormal leading to altered mental status,
motor and sensory deficits, altered behavior, speech or movement disorders, speech changes
Meningitis vs encephalitis
(1) Test meningeal irritation
(a) Brudzinski sign – spontaneous flexion of hips during passive flexion of the neck
(b) Kernig sign – inability or reluctance to allow full extension of knee when hip is flexed at 90 degrees
(2) Lab testing
(a) Lumbar puncture to evaluate CSF
(b) LP should be delayed if there are signs of increased intracranial pressure
1) Papilledema
2) Focal neurological deficit
3) Abnormal level of consciousness
(c) Initiation of treatment should not be delayed if there is high clinical suspicion of meningitis.
Diagnosis of meningitis
(1) Medical emergency with close to 100% fatality rate if left untreated
(2) Need antibiotics that can cross blood-brain barrier
(3) Empiric treatment covers most common bacterial etiologies and focuses on decreasing acute inflammation.
(a) Ceftriaxone (rocephin)
1) Dose: 2g IV Q12Hr
(b) Vancomycin (not in AMAL)
(c) Dexamethasone
1) Dose: 0.15mg/kg IV Q6Hr
2) Decreases acute inflammation in CNS
3) Studies demonstrate that there are less neurological long term complications
(d) If aseptic meningitis due to HSV is suspected (eg, concomitant genital lesions), empiric therapy with acyclovir IV is recommended
Acute Management and treatment meningitis
1) Exposed crew – Ciprofloxacin (Cipro) - is a Fluoroquinolone antibiotic
a) Dose: 500 mg PO x1
b) MOA: Bactericidal; inhibits DNA gyrase and topoisomerase IV
c) Adverse Reactions: Photosensitivity, serum sickness, seizures, tendon
rupture, nephrotoxicity
d) Contraindications: QT prolongation, G6PD deficiency, tendon disorder,
renal impairment, hepatic impairment, seizures
2) Mask patient and medical personnel in close proximity
3) Ensure vaccinations are current
a) Meningiococcal, S. penumoniae, and H. influenza vaccinations
Prophylaxis meningitis
