XIII.1. A patient presents with a 2-day history of severe headache and neck stiffness and a 1-day history of diffuse rash and fever.
Results of cerebrospinal fluid evaluation are 1,500 white blood
cells/µL (predominantly neutrophils), glucose 20 mg/dL, and
protein 60 mg/dL. What is the most likely cause of the patient’s
syndrome?
a. Viral meningitis
b. Viral encephalitis
c. Bacterial meningitis
d. Mycobacterial meningitis
e. Fungal encephalitis
XIII.1. Answer c.
Meningitis refers to inflammation of the leptomeninges
caused by either infectious or noninfectious processes.
Encephalitis refers to inflammation of the leptomeninges
and the brain parenchyma as evidenced by focal or diffuse
symptoms referable to the brain. This patient has isolated
pain without other neurologic symptoms and a cerebrospi-
nal fluid profile consistent with bacterial meningitis (low
glucose and high protein levels and a markedly elevated
white blood cell count with predominantly neutrophils).
XIII.2. One week after receiving an epidural injection in the lumbar spine, a patient presents with fever, back pain, and pain radiating to the legs. What should be the next step in the evalua-
tion of this patient?
a. Computed tomography of the thoracic spine and lumbar spine
b. Magnetic resonance imaging of the lumbar spine
c. Lumbar puncture and cerebrospinal fluid analysis
d. A 1-week course of corticosteroids
e. Indium scan of the spine
XIII.2. Answer b.
The next step would be magnetic resonance imaging of the
lumbar spine to determine whether an epidural abscess is
present. Cerebrospinal fluid evaluation should not be per-
formed before imaging.
XIII.3. What would be the most likely cause of bacterial meningitis in an 18-year-old college student who lives in a dormitory?
a. Group B streptococci
b. Listeria monocytogenes
c. Neisseria meningitidis
d. Haemophilus influenzae
e. Mycobacterium tuberculosis
XIII.3. Answer c.
The most common cause of bacterial meningitis in patients
aged 10 to 19 years is Neisseria meningitidis (see also
Table 110.1).
XIII.4. A 30-year-old woman presents with right facial weakness of the upper and lower portions of her face. A few vesicles have
appeared around the right external auditory meatus. Which
virus is the most likely causative agent?
a. Cytomegalovirus
b. West Nile virus
c. Herpes simplex virus type 1
d. Epstein-Barr virus
e. Varicella zoster virus
XIII.4. Answer e.
Ramsay Hunt syndrome is caused by viral reactivation of
varicella zoster virus in the geniculate ganglion of the
facial nerve, resulting in facial paresis and a herpetic rash
in the external auditory canal.
XIII.5. A 70-year-old man had fever, confusion, and shuffling gait
shortly after a summer camping trip. He also had a single gen-
eralized seizure. Two weeks later, he had severe flaccid paresis
of the right upper extremity. Which virus is the most likely
causative agent?
a. Poliovirus
c. Japanese encephalitis virus
d. Eastern equine encephalitis virus
e. Powassan virus
XIII.5. Answer b.
West Nile virus may cause meningoencephalitis in addi-
tion to asymmetric lower motor neuron paralysis related to
anterior horn cell damage.
Which of the following is true regarding Epstein-Barr virus (EBV)?
a. Less than 10% of the adult population is seropositive
b. EBV is detected in the majority of central nervous system lym-
phomas in patients with HIV infection
c. Patients with transverse myelitis due to EBV should be treated
with corticosteroids
d. EBV is the most common cause of idiopathic facial paralysis
e. The best diagnostic test for EBV is viral culture
XIII.6. Answer b.
EBV is detected in the majority of primary central nervous
system lymphomas in patients with AIDS. Nearly 100% of
the population is seropositive by adulthood. Primary infec-
tion can result in infectious mononucleosis. Neurologic
complications of acute infection are rare (<1% of patients)
but include meningoencephalitis, transverse myelitis,
polyradiculoneuropathy, optic neuritis, and cranial nerve
neuropathies, including facial palsy. Treatment is support-
ive. Polymerase chain reaction for EBV DNA in cerebrospi-
nal fluid can be performed diagnostically.
Which of the following is true regarding HIV-associated dementia?
a. The CD4 cell count is usually 250 to 500/μL
b. Magnetic resonance imaging (MRI) of the brain shows subcorti-
cal T2-hyperintense lesions
c. It is caused by concomitant Epstein-Barr virus infection
d. Patients often have aphasia and hemineglect
e. The incidence has not changed with the use of highly active
antiretroviral therapy (HAART)
XIII.7. Answer b.
MRI shows diffuse T2-weighted signal abnormalities in
the periventricular white matter and generalized atrophy.
HIV-associated dementia usually occurs late in an HIV
infection, when the CD4 cell count is less than 200/μL,
and is thought to be related to the HIV infection itself. The
incidence has decreased considerably since the introduc-
tion of HAART. Clinically, HIV-associated dementia is
characterized by slowly progressive behavioral changes
and subcortical dementia.
A 57-year-old man who has been treated with a stable regimen
of highly active antiretroviral therapy (HAART) for 6 years is
referred for neurologic evaluation of subacute progressive cog-
nitive decline and personality changes. On examination, no
focal neurologic deficits are identified. Magnetic resonance
imaging of the brain shows faint symmetrical periventricular
white matter T2-signal abnormalities but is otherwise unre-
markable. His most recent CD4 count was normal, and a
plasma HIV RNA viral load is undetectable. Cerebrospinal fluid
(CSF) analysis shows a mildly elevated protein level (58 mg/dL)
and a cell count of 7/μL. What would be the best next step?
a. Polymerase chain reaction (PCR) for CSF JC virus
b. Brain biopsy
c. Measurement of CSF HIV RNA viral load
d. Empirical therapy for suspected central nervous system (CNS)
toxoplasmosis
e. PCR for Epstein-Barr virus
XIII.8. Answer c.
Patients with HIV infection who are receiving HAART can
present with neurologic symptoms with suppressed
peripheral viremia and normal CD4 counts but a discor-
dant elevation in CSF HIV RNA. This phenomenon is
caused by the disparate effects of antiretroviral therapy
between the CNS and the blood compartments, leading to
unchecked infection in the CNS (called CSF viral escape).
Changing the antiretroviral regimen to optimize CNS pen-
etrance usually leads to clinical and radiologic improve-
ment. On the basis of the clinical presentation, imaging
findings, and normal CD4 count, it is unlikely that the
patient has progressive multifocal leukoencephalopathy
or CNS toxoplasmosis.
A patient with HIV infection and CD4 cell counts less than
150/μL presented with seizure. Magnetic resonance imaging
(MRI) of the brain demonstrated multiple ring-enhancing
lesions. Toxoplasma serology was abnormal, and the patient
was treated with anti-Toxoplasma agents for 4 weeks. Follow-
up MRI demonstrated additional lesions. What should the next
step in management include?
a. Biopsy of a surgically accessible lesion
b. Cerebrospinal fluid (CSF) evaluation for toxoplasmosis
c. Corticosteroid therapy
d. Higher doses of anti-Toxoplasma agents
e. CSF evaluation for JC virus
XIII.9. Answer a.
See Figure 112.3. If a patient has lesions that are typical for
toxoplasmosis but has no response to anti-Toxoplasma
therapy, a biopsy should be considered to rule out other
entities such as other infectious agents or lymphoma.
XIII.10. A 42-year-old female immigrant from Jamaica presents with a
6-month history of progressive leg weakness and urinary reten-
tion. On examination she has spastic paraparesis. She is HIV
negative and has no prior history of neurologic dysfunction.
Family history is unremarkable. Magnetic resonance imaging of
the brain and spinal cord does not show any abnormalities.
Cerebrospinal fluid (CSF) analysis reveals mild lymphocytic
pleocytosis with 26 cells/μL and 5 unique oligoclonal bands.
What is the best next step?
a. Initiate disease-modifying therapy for progressive multiple
sclerosis
b. Order genetic testing for hereditary spastic paraplegia (HSP)
c. Order serology for human T-lymphotropic virus (HTLV)
d. Order cryptococcal antigen
e. Reorder HIV testing because the presentation is consistent with
HIV-associated vacuolar myelopathy
XIII.10. Answer c.
The patient has spastic paraparesis and mildly inflamma-
tory CSF. She is HIV negative, but she immigrated from
Jamaica, where HTLV-1 is endemic, so she should be tested
for HTLV-1 because her presentation is consistent with
tropical spastic paraparesis (HTLV-1‒associated myelopa-
thy). With the absence of MRI lesions, multiple sclerosis is
less likely. Although HSP is possible, the patient has no
family history, and the CSF is inflammatory.
XIII.11. A 34-year-old man presents with a 1-day history of headache,
fever, and neck pain. He lies in bed with his eyes shut in
severe pain. Kernig and Brudzinski signs are positive, and
computed tomography of the head does not show any abnor-
malities. Before lumbar puncture is performed, which antimi-
crobials should be given empirically?
a. Acyclovir and ceftriaxone
b. Acyclovir, cefazolin, and ampicillin
c. Cefepime and ampicillin
d. Ceftriaxone and vancomycin
e. Cephalexin and vancomycin
III.11. Answer d.
Empirical treatment of bacterial meningitis is based on the
use of a third- or fourth-generation cephalosporin and van-
comycin. Cefazolin and cephalexin are first-generation
cephalosporins. Patients with risk factors for an infection
with Listeria monocytogenes should also be treated with
ampicillin. Acyclovir, commonly used for viral meningitis
and encephalitis, would not be indicated in this situation.
XIII.12. Which of the following is not a risk factor for meningitis due
to Listeria?
a. Pregnancy
b. Alcohol misuse
c. Diabetes mellitus
d. Adolescence
e. Contaminated food
XIII.12. Answer d.
Listeria monocytogenes is thought to account for about 8%
of community-acquired acute bacterial meningitis and is
typically acquired from contaminated food. Other risk fac-
tors for a Listeria infection include age older than 50 years,
pregnancy, diabetes mellitus, alcohol abuse, immune sup-
pression or compromise, and other chronic illness.
XIII.13. Which of the following is useful for distinguishing a cerebral
abscess from a neoplasm?
a. Cerebrospinal fluid (CSF) analysis, including cell count and
Gram stain
b. Computed tomography (CT) of the head with and without a
contrast agent
c. Presence of a fever
d. Contrast-enhanced magnetic resonance imaging (MRI),
diffusion-weighted imaging, and apparent diffusion coefficient
mapping
e. CT perfusion imaging
XIII.13. Answer d.
Diagnosis is made from recognition of the clinical syndrome
and the finding of a ring-enhancing lesion on contrast-
enhanced MRI. In addition, diffusion-weighted imaging
and apparent diffusion coefficient sequences show bright
restricted diffusion within the lesion, a finding that distin-
guishes an abscess from other ring-enhancing lesions such
as a neoplasm. CSF analysis may be nonspecific, and it
should not be used for diagnosis of a bacterial abscess
because if a patient has a space-occupying lesion, lumbar
puncture can increase the risk of herniation.
XIII.14. A 45-year-old woman from Wisconsin has acute right facial
paralysis after hiking in a heavily wooded area in early
autumn. She has upper and lower facial weakness, including
difficulty closing her right eye. Which of the following should
you do?
a. Treat her condition as idiopathic Bell palsy
b. Order contrast-enhanced magnetic resonance imaging (MRI) of
the brain
c. Order the enzyme-linked immunosorbent assay (ELISA) test for
anti-Borrelia antibodies
d. Order cerebrospinal fluid (CSF) analysis
e. Order nerve conduction studies
XIII.14. Answer c.
A patient who lives where Lyme disease is endemic and
who has lower motor neuron facial weakness should be
assessed for possible Lyme disease. The diagnosis is made
by having a high degree of clinical awareness and testing
for anti-Borrelia antibodies with the recommended 2-step
method (ELISA for screening and immunoblot for subse-
quent confirmation). MRI and CSF analysis are not neces-
sary unless the patient has additional features that suggest
neuroborreliosis (eg, seizure, focal neurologic deficit, or
myelopathic symptoms).
XIII.15. A patient who received a solid organ transplant several years
ago presents with cavernous sinus thrombosis and sinus dis-
ease apparent on computed tomography. Which of the follow-
ing organisms is most likely involved in this presentation?
a. Histoplasma
b. Candida albicans
c. Aspergillus
d. Coccidioides immitis
e. Treponema pallidum
XIII.15. Answer c.
Aspergillus is an invasive vascular fungus. Patients with
invasive sinus disease and central nervous system exten-
sion may have sinus pain and congestion, headache,
vision changes, and photosensitivity. Vascular thrombosis
and unilateral proptosis may develop.
XIII.16. Which of the following statements about coccidioidomycosis is true?
a. This condition occurs predominantly in the Ohio River Valley
b. Clinical manifestations outside the central nervous system
(CNS) are rare
c. Abscesses are the most common neurologic manifestation
d. Lymphocytes and eosinophils may be present in the cerebro-
spinal fluid (CSF)
e. Coccidioides invades the large arteries
XIII.16. Answer d.
Coccidioidomycosis is endemic in the southwestern United
States, northern Mexico, and parts of Central and South
America. Pulmonary involvement is most common, but CNS
infections may develop weeks to months after the onset of
pulmonary disease. Chronic meningitis and hydrocephalus
are the most common neurologic manifestations. The CSF
examination typically shows a lymphocytic pleocytosis.
Eosinophils may also be present. Coccidioidomycosis does
not involve the vasculature.
XIII.17. Which of the following is not a risk factor for invasive Candidiasis?
a. Parenteral nutrition
b. HIV infection
c. Extensive burn injury
d. Prolonged antibiotic therapy
e. Age 5 to 25 years
XIII.17. Answer e.
All the items listed are risk factors for invasive candidiasis
except age 5 to 25 years. The age groups at high risk are
younger than 1 year and older than 65 years. See also Box
114.1.
XIII.18. Which description best characterizes amebic meningoenceph-
alitis in most patients?
a. Clinically silent infection
b. Mild, self-limited disease
c. Moderate disease that typically responds well to antimicrobial
therapy
d. Severe disease that typically responds well to antimicrobial
e. Severe disease that has a grave prognosis despite antimicrobial
XIII.18. Answer e.
The prognosis is usually extremely poor. Most patients
proceed to coma and death within 4 to 6 days after clinical
onset, usually with an elevated intracranial pressure lead-
ing to herniation.
XIII.19. A 22-year-old college student spent 1 semester in rural Mexico.
Several weeks after returning, she had a seizure and headache.
Magnetic resonance imaging showed numerous hypodense,
cystic lesions. What is the next step to secure the diagnosis?
a. Biopsy of a lesion
b. Cerebrospinal fluid examination
c. Taenia solium antibody test
d. Toxoplasma antigen test
e. CD4 cell count
XIII.19. Answer c.
The description is consistent with neurocysticercosis
caused by T solium. The diagnosis is often made from the
history (travel in an area where the disease is endemic),
clinical presentation, and brain imaging. Antibody detec-
tion of T solium is widely available with enzyme-linked
immunosorbent assay, although enzyme-linked immuno-
electrotransfer blot assay provides higher sensitivity and
specificity and is available from the Centers for Disease
Control and Prevention. Evaluation of serum rather than
cerebrospinal fluid is preferred because serum testing has
greater sensitivity. Although sensitivity is high in patients
with multiple lesions, the assay can be negative in those
presenting with a single lesion. The presence of antibodies
merely indicates exposure to T solium and must be inter-
preted within the clinical context, particularly for patients
from endemic regions.
XIII.21. A 66-year-old man from Brazil has dementia, ataxia, and
myoclonus that have developed over 2 months. Which form of
Creutzfeldt-Jakob disease (CJD) is most likely?
a. Familial CJD
b. Iatrogenic CJD
c. Mutant CJD
d. Sporadic CJD
e. Variant CJD
XIII.21. Answer d.
Sporadic CJD accounts for 85% to 90% of all cases of CJD.
XIII.20. A 25-year-old patient with a newly diagnosed HIV infection
and a CD cell count of 74/μL was evaluated for encephalopa-
thy. Magnetic resonance imaging (MRI) of the brain showed a
ring-enhancing lesion, and cerebrospinal fluid (CSF) analysis
showed a lymphocytic pleocytosis. Tests for microorganisms,
including polymerase chain reaction testing for Toxoplasma
gondii and Epstein-Barr virus, were negative. The patient was
given empirical therapy for toxoplasmosis with pyrimeth-
amine, sulfadiazine, and folinic acid. Four weeks later, MRI
shows enlargement of the previously noted lesion and new
enhancing lesions. What is the next step in management?
a. Increase the dose of pyrimethamine
b. Add corticosteroids
c. Consider biopsy of a surgically accessible lesion
d. Add clindamycin
e. Continue the present treatment because the lesions would not
be expected to improve for 6 months
XIII.20. Answer c.
Empirical therapy for presumed toxoplasmic encephalitis
is usually recommended for patients with AIDS who present with ring-enhancing lesions when CSF results are
either unrevealing or cannot be obtained because of mass
effect. If the patient has no response within 2 weeks, brain
biopsy should be considered, and the main differential
diagnosis would be primary lymphoma of the central ner-
vous system.
XIII.22. Which PRNP genotype is most likely in a patient with sporadic
Creutzfeldt-Jakob disease (CJD)?
a. Codon 129 methionine-methionine
b. Codon 129 methionine-valine
c. Codon 129 valine-valine
d. Codon 178 aspartic acid-aspartic acid
e. Codon 178 aspartic acid-asparagine
XIII.22. Answer a.
The methionine-methionine (MM) genotype at codon
129 of the prion protein gene occurs in 72% of patients
with sporadic CJD (and in 100% of patients with variant
CJD).
XIII.23. In a patient with suspected sporadic Creutzfeldt-Jakob dis-
ease (CJD), which of the following would be most accurate
diagnostically?
a. Elevation of 14-3-3 protein
b. Elevation of neuron-specific enolase
c. Real-time quaking-induced conversion (RT-QuIC)
d. Elevation of S-100 protein
e. Elevation of tau protein
XIII.23. Answer c.
RT-QuIC has the highest sensitivity and specificity for spo-
radic CJD. Neuron-specific enolase, 14-3-3 protein, tau
protein, and S-100 protein are elevated in many diseases
in which there is rapid neuronal loss.
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