Learning Points:

General approach

• Obtaining a thorough history is key in assessing altered mental status
• When examining patients with fevers, headaches and altered mental status, make sure to conduct a Jolt accentuation test in addition to Kernig’s and Brudzinski’s  to increase sensitivity of detecting meningitis
• Obtain blood cultures prior to starting empiric antibiotics
• Make sure to obtain CT head/ MRI brain prior to lumbar puncture if concerned for encephalitis
• Please note, lumbar puncture can be performed after initiation of antibiotics

WNV encephalitis

• Clinical presentation: variable however patients can be asymptomatic 60-80% of the time or present with fatigue, memory impairment, weakness, headache and neurological deficits
• CSF findings: elevated protein (<150 mg/dL) and moderate pleocytosis (<500 cells/microL) with predominance of lymphocytes, however in early infection, neutrophils may predominate; positive WNV IgM in serum or CSF, seroconversion usually occurs between 4-10 days after viremia detected
• Treatment: primarily supportive care

Click here: http://www.publichealth.lacounty.gov/acd/VectorWestNile.htm for an updated incident report on WNV in California

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