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Weakness and Dizziness Answers 397

from disseminated erythematous macules into hemorrhagic pustular lesions.
Serious complications may include meningitis, osteomyelitis, and endocarditis.


367.The answer is b.(Tintinalli et al, p 970.)This patient has Lyme disease,
the most common vector-borne zoonotic infection in the United States.
The spirochete, Borrelia burgdorferi,is transmitted to humans by the deer
tick Ixodes,and although the risk of infection after a bite is about 3% in
highly endemic areas (Northeast and Midwest); it increases to 25% if the tick
is attached for longer than 72 hours. This patient presents in the second stage of
Lyme disease. The first stage involves the development of erythema migrans,
a spreading annular erythematous lesion with central clearing occurring
commonly at the tick bite site 2 to 20 days after the bite. The second stage
typically occurs within 6 months of the initial infection and is characterized
by fever, fatigue, arthralgias, neuropathies (ie, Bell palsy), cardiac abnormalities
(ie, myocarditis presenting with conduction delay), and multiple annular
lesions. Tertiary stage of Lyme disease occurs year after the infection and
consists of chronic arthritis, subacute encephalopathy, and polyneuropathy.
Primary and secondary stages of the disease are treated with doxycycline.
Tertiary stage is treated with IV ceftriaxone or penicillin.
Some sources refer to any facial nerve palsy as Bell palsy (a), whereas
most consider Bell palsy an idiopathic facial nerve paralysis. An easy way to
look at it is that facial nerve paralysis may have an identifiable cause or may
be idiopathic, in which case it is referred to as Bell palsy. In either case,
exclude Lyme disease in patients with facial nerve palsy by sending Lyme titer
levels. Ramsay Hunt syndrome (c)is a facial nerve palsy secondary to varicella-
zoster virus (VZV). VZV causes chicken pox and may remain dormant in
nerve ganglia for years. In addition to cranial nerve VII paralysis, the syndrome
is characterized by severe ear pain, vertigo, hearing loss, and classic shingles
in the ear. A brain tumor (d)may cause facial nerve compression centrally
and may present with partial facial paralysis with forehead sparing. The
forehead is bilaterally innervated, and the intact contralateral branch provides
motor function. RMSF (e)is a tick-borne Rickettsia rickettsiiinfection. The
disease involves constitutional symptoms of high fever, myalgias, severe
headache, and a characteristic blanching erythematous macular rash which
spreads from distal extremities to the trunk.


368.The answer is d.(Rosen, pp 1714-1723.) This patient is tachypneic,
probably as a result of some underlying anxiety, which has resulted in

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