Case 1

 A previously healthy 22-year-old college
student is brought to the emergency
department by her parents 20 minutes after
they observed her having a seizure. After the
seizure, she was confused and had difficulty
thinking of some words. She has had a
headache, cough, and fever for 3 days treated
with acetaminophen and dextromethorphan.
Her temperature is 38.9°C (102°F).
Neurologic examination shows diffuse
hyperreflexia. On mental status examination,
she is confused and has short-term memory
deficits. She has difficulty naming objects and
makes literal paraphasic errors. An MRI of the
brain shows bitemporal hyperintensities. A
lumbar puncture is done; cerebrospinal fluid
analysis shows an erythrocyte count of
340/mm3, a leukocyte count of 121/mm3 (88%
monocytes), and a protein concentration of 78
mg/dL. Which of the following is the most
likely diagnosis?
(A) Bacterial meningitis
(B) Dextromethorphan intoxication
(C) Herpes simplex encephalitis
(D) HIV encephalopathy
(E) Reye syndrome
(F) Syphilis

Case 2

A 48-year-old man with alcoholism comes to
the physician because of fever, a facial rash,
and rapidly progressive swelling of the left
side of the face. The swelling began 12 hours
ago when a scab on his left cheek began to
itch. His temperature is 39.2°C (102.5°F). He
is unable to open his left eye because of the
severity of the swelling. Which of the
following is the most likely causal organism?
(A) Group A streptococcus
(B) Haemophilus influenzae
(C) Herpes simplex virus
(D) Neisseria meningitidis
(E) Streptococcus pneumoniae