06-12-2009, 08:33 AM
During the summer, a 71-year-old man is brought to the emergency department (ED) by his grandson after the man becomes confused and tremulous. He was in stable health until 2 days ago when he complained of a headache and fever. Medical history is coronary vascular disease status postmyocardial infarction 4 years ago. Medications are carvediol and chlorthalidone. The man does not have a history of recent nonsteroidal antiinflammatory drug (NSAID) use. He is retired since age 65 and has since lived on his farm in upstate New York. Vital signs are temperature 100.7°F (38.2°C), blood pressure (BP) 140/90 mm Hg, heart rate 85 beats per minute and respiration rate 14 breathsper minute. Physical examination is notable for decreased level of consciousness with drowsiness, disorientation to place and time and lack of attention to surroundings. A resting hand tremor is present. There is mild temporal optic disk edema and bilateral (each eye) multiple white subretinal choroidal infiltrates at the posterior poles. Cranial nerves II-XII are grossly intact, neck is supple with full range of motion. The only other contributory physical finding is generalized lymphadenopathy without organomegaly. Notable lab values are white blood count (WBC) 6 k/uL with 4% lymphocytes. Computed tomography (CT) brain scan shows no evidence of acute disease. Magnetic resonance imaging (MRI) brain scan shows enhancement of the periventricular regions bilaterally. Lumbar puncture shows normal opening pressure, moderate cerebrospinal fluid (CSF) pleocytosis with lymphocyte predominance with mild elevated protein, normal glucose and lactic acid levels and no red blood cells (RBCs). CSF gram stain is negative. Electroencephalogram (EEG) scan shows generalized delta wave activity with irregular diffuse slowing and no unilateral focal temporal lobe electrical abnormalities. What is the probable diagnosis?
A. Coxsackievirus encephalitis
B. Eastern equine encephalitis
C. Herpes simplex virus (HSV) “1 encephalitis
D. Saint Louis encephalitis
E. West Nile virus encephalitis
A. Coxsackievirus encephalitis
B. Eastern equine encephalitis
C. Herpes simplex virus (HSV) “1 encephalitis
D. Saint Louis encephalitis
E. West Nile virus encephalitis