Neurology Flashcards
A boy is found to have patches of retinal pigmentation after he is brought to clinical attention
because of several episodes of seizures. He subsequently is diagnosed with Aicardi syndrome
following an MRI of the brain and cervical spine.
What abnormality was seen on imaging to prompt
the diagnosis of Aicardi syndrome?
A. Absence of the septum pellucidum
B. Dandy-Walker malformation
C. Fusion of the cervical vertebrae
D. Agenesis of the corpus callosum
E. Chiari type 3 malformation
D. Agenesis of the corpus callosum
Agenesis of the corpus callosum is seen along with mental retardation, epilepsy, and patches of retinal pigmentation in Aicardi syndrome. The syndrome is inherited in an X-linked dominant fashion and is lethal in most males. (A) Absence of the septum pellucidum has many etiologies and is seen in Morsier syndrome (septo-optic dysplasia). (B) A Dandy-Walker malformation is a partial or complete absence of the cerebellar vermis. (C) Fu- sion of any two of the cervical vertebrae is associ- ated with Klippel-Feil syndrome. (E) A Chiari type 3 malformation is characterized by an occipital encephalocele containing neuroectodermal tissues from the posterior fossa and is associated with hydrocephalus.
A positive Romberg sign indicates a disturbance
of what structure(s)?
A. Posterior columns
B. Cerebellar vermis
C. Lateral geniculate body
D. Cerebellar hemisphere
E. Corticospinal tract
A. Posterior columns
A positive Romberg test is not a test of cerebellar function. Patients with cerebellar ataxia are not able to balance even with their eyes open. The cerebellum is responsible for unconscious proprio- ception and receives input from the dorsal nucleus of Clarke, with information traveling through the ipsilateral dorsal spinocerebellar tract. Vestibular disorders can have a positive Romberg sign; how- ever, the sign most commonly is seen in patients with loss of conscious proprioception or dorsal column–medial longitudinal fasciculus system dysfunction.
A 7-year-old boy presents to the emergency department after suffering a first-time seizure at
home. His mother says that he had been febrile recently and seemingly slightly confused. On exam,
the child is lethargic without focal deficits. Mild
papilledema is seen on funduscopic examination.
Routine laboratory studies are unremarkable, but a
lumbar puncture reveals cerebrospinal fluid with
leukocytosis and an elevated protein content. Multiple cultures are sent to the lab. An MRI with
FLAIR sequence reveals an abnormality within
the left temporal lobe. Electroencephalography
demonstrates periodic lateralizing epileptiform
discharges from the left temporal lobe. What are
the most likely diagnosis and next step in the patient’s management?
A. Varicella zoster encephalitis; begin intravenous acyclovir
B. Varicella zoster encephalitis; await culture
results before initiating treatment
C. Herpes simplex encephalitis; begin intravenous acyclovir
D. Herpes simplex encephalitis; await culture
results before initiating treatment
C. Herpes simplex encephalitis; begin intravenous acyclovir
Herpes simplex virus (HSV) encephalitis pres- ents acutely and most commonly with fever and an altered level of consciousness often accompanied by seizures. There is a predilection for the tempo-
ral and orbitofrontal lobes with edema in these areas visualized on MRI (bilateral lesions raise the suspicion for HSV encephalitis). Treatment should be initiated quickly if a patient has fever, encepha- lopathy, supporting cerebrospinal fluid studies, and another supporting study. (A, B) Varicella zoster encephalitis more commonly affects immunocom- promised individuals and typically follows cutane- ous herpes zoster.
Apert syndrome is distinguished from Crouzon syndrome as individuals with Apert, and not Crouzon,
syndrome tend to have:
A. Absence of a cleft palate
B. Normal intelligence
C. Mental retardation
D. Complex syndactyly
C. Mental retardation
Both Apert and Crouzon syndromes are associ- ated with craniosynostosis and a high incidence of hydrocephalus, and are inherited in an autosomal dominant manner. Individuals with Crouzon syn- drome usually are of normal intelligence once the hydrocephalus is treated. On the other hand, individuals with Apert syndrome have with men- tal retardation, complex syndactyly, short thumbs, and cleft palates.
Damage to what neural structure(s) is most associated with prosopagnosia?
A. Mid-fusiform gyrus and inferior occipital gyrus
B. Bilateral amygdalae
C. Mesial temporal lobe
D. Calcarine sulcus and dominant angular gyrus
E. Superior parietal lobule and supramarginal
gyrus
A. Mid-fusiform gyrus and inferior occipital gyrus
Mid-fusiform gyrus and inferior occipital gyrus
Damage to or inappropriate development of the mid-fusiform and inferior occipital gyri inde- pendently and with either unilateral or bilateral defects are associated with prosopagnosia (diffi- culty with face recognition). (B) Kluver-Bucy syn- drome occurs in bilateral amygdala lesions. It is associated with hyperoral and hypersexual behav- iors, visual agnosia, and hypomotility. (C) Mesial temporal lobe lesions result in long-term memory deficits. (D) Damage to the dominant angular gyrus results in dysgraphia (writing apraxia). (E) The superior parietal lobule and supramarginal gyrus are part of the association cortex. Damage to these areas can cause contralateral astereognosis, result- ing in failure to recognize objects when felt with the contralateral hand but not when visualized.
A 62-year-old man presents with masked facies
without tremor. His family members report that
over the past year, the patient had multiple falls,
dysarthria, and dysphagia. They report he has
had some personality changes. On exam, he has a
hyperactive jaw jerk, axial dystonia, and downgaze paresis. You suspect the patient has what
condition?
A. Parkinson disease
B. Olivopontocerebellar degeneration
C. Progressive supranuclear palsy
D. Multiple system atrophy
C. Progressive supranuclear palsy
The progressive supranuclear palsy (Steele- Richardson-Olszewski syndrome) triad is pro- gressive supranuclear ophthalmoplegia (paresis of voluntary eye movements with down-gaze palsy and frequent falls as a result), pseudobulbar palsy (masked facies with dysarthria, dysphagia, and a hyperactive jaw jerk), and axial dystonia. Patient with this condition do not walk bent forward and do not have a tremor despite progressive supra- nuclear palsy being characterized as pseudo- parkinsonism. Progressive supranuclear palsy can be differentiated from Parkinson disease by a poor response to levodopa in the former. (A) Triad of parkinsonism is resting tremor, cogwheel rigidity, and bradykinesia. (B) Olivopontocerebellar degen- eration is related to multiple system atrophy and often presents with cerebellar ataxia, dysarthria, and dysphagia without paresis. (D) Multiple sys- tem atrophy (Shy-Drager syndrome) is a Parkinson plus syndrome. It is a progressive disorder of the central and autonomic nervous systems with idio- pathic orthostatic hypotension.
Bilateral periodic lateralizing epileptiform discharges (PLEDs) that are not reactive to painful
stimulation are suggestive of what condition?
A. Subacute sclerosing panencephalitis
B. Creutzfeldt-Jakob disease
C. Herpes simplex encephalitis
D. Hepatic encephalopathy
C. Herpes simplex encephalitis
Bilateral periodic lateralizing epileptiform dis- charges (PLEDs) are seen with acute focal insults and in 85% of cases of herpes simplex encephali- tis. (A) Subacute sclerosing panencephalitis has a pathognomonic pattern of periodic high-amplitude complexes with accompanying myoclonic jerks that does not change with painful stimulation. (B) PLEDs are defined as spikes occurring at regular intervals. The electroencephalogram in sporadic Creutzfeldt-Jakob disease often shows bilateral sharp waves that may resemble PLEDs but are reactive to painful stimulation. (D) Hepatic enceph- alopathy may show nonspecific triphasic waves on electroencephalography.
Transcranial Doppler can detect changes in flow
velocities in the cerebral arteries. Vasospasm is differentiated from a hyperemic state by:
A. A mean flow velocity greater than 120 cm/s,
indicating vasospasm
B. Measuring the middle cerebral to internal carotid artery velocity ratio
C. Checking for flow symmetry on the contralateral side
D. Measuring the velocity/vessel diameter ratio
E. Determining the direction of flow
B. Measuring the middle cerebral to internal carotid artery velocity ratio
A Lindegaard ratio (VMCA/VICA) greater than 3 is seen in vasospasm. In a hyperemic state, velocities in both the middle cerebral and internal carotid arteries are elevated equally, so the ratio is near 1. (A) Multiple factors can influence cerebral artery flow velocity, including systemic blood pressure, cerebral blood flow, and cerebral perfusion. Tran- scranial Doppler measures the cervical carotid and intracranial artery velocities. Elevated flow veloc- ity more than 100 cm/s can be seen in both hyper-
emic and vasospastic states. (C) Vasospasm can affect the circulation bilaterally, so symmetry is not a key differentiating factor. (D) Vessel diameter is not a determining factor in either state. (E) Ante- grade versus retrograde flow is not used to differ- entiate between hyperemia and vasospasm.
What involuntary movement disorder typically
persists during sleep?
A. Hemifacial spasm
B. Blepharospasm
C. Athetosis
D. Facial myokymia
A. Hemifacial spasm
Hemifacial spasm and palatal myoclonus are involuntary movement disorders that persist during sleep. (B) Blepharospasm is sustained, abnormal blinking. It involves the orbicularis oculi muscle only (in contrast to hemifacial spasm, which involves various muscles on one side of the face). Blepharo- spasm typically ceases during sleep. (C) Athetosis is slow, writhing movements of the distal muscles (fingers, hands, toes, feet, and even face). (D) Facial myokymia is continuous facial spasms secondary to multiple sclerosis or a brainstem glioma. One of the treatments is rest.
The Cantu system for concussion grading uses what
three variables to determine severity?
A. Loss of consciousness, transient confusion, and
symptom duration
B. Loss of consciousness, posttraumatic amnesia,
and neurologic deficits
C. Eye opening, motor response, and verbal
response
D. Loss of consciousness, posttraumatic amnesia,
and symptom duration
D. Loss of consciousness, posttraumatic amnesia,
and symptom duration
The Cantu concussion grading system is a three- grade system based on posttraumatic amnesia (PTA), loss of consciousness (LOC), and symptom duration. The scoring system is as follows: grade 1: no LOC, PTA less than 30 minutes, and postconcus- sion symptoms lasting no more than 15 to 30 min- utes; grade 2: LOC less than 1 minute and PTA and symptoms lasting 30 minutes to 24 hours; grade 3: LOC of 1 minute or longer, PTA lasting more than 24 hours, and symptoms lasting as long as 1 week. (A) The American Academy of Neurology system uses a progressive three-grade system for concus- sion grading based on transient confusion, symp- tom duration, and loss of consciousness. (B) The Ruff Concussion system is a progressive three- grade system based on loss of consciousness, post- traumatic amnesia, and neurologic deficits. (C) The Glasgow Coma Scale ranges from a minimum score of 3 to a maximum score of 15. The score is the sum of the individual scores for eye opening, verbal response, and motor response. The scoring system is as follows: eye opening score: spontaneous (4), to speech (3), to pain (2), no response (1); verbal response score: alert and oriented (5), confused (4), inappropriate words (3), incomprehensible sounds (2), no response (1); motor response score: follows commands (6), localizes to pain (5), with- draws to pain (4), flexor (decorticate) posturing (3), extensor (decerebrate) posturing (2), no re- sponse (1).
A 49-year-old man presents with left elbow pain.
His symptoms have not improved with rest, ice,
splinting, and analgesics. He has noticed progressive weakness in extension of his thumb and fingers without weakness of his wrist or arm. There is
no sensory loss. What is the suspected diagnosis?
A. Radial nerve neuropathy in the upper arm
B. Tennis elbow
C. Posterior interosseous neuropathy
D. C8 radiculopathy
E. Radial tunnel syndrome
C. Posterior interosseous neuropathy
The posterior interosseous nerve is a continua- tion of the deep branch of the radial nerve. Entrap- ment occurs in the forearm at the arcade of Frohse, causing extensor weakness of the thumb and fin- gers without involvement of the wrist extensors or triceps. This is a motor syndrome, and there is no sensory loss as seen in a radiculopathy. (A) A radial nerve palsy can occur at the axilla, causing triceps and distal weakness or at the mid-upper arm (spi- ral groove or intramuscular septum), sparing the triceps but causing weakness of wrist and finger extensors. (B) Tennis elbow (also known as lateral epicondylitis) is an inflammatory process of the tendons on the lateral aspect of the elbow. This results in pain of the extensor muscles of the fore- arm, wrist, and fingers. The tendon of the extensor carpi radialis brevis is usually involved. (D) A C8 radiculopathy results in flexion weakness of the index and middle fingers and paresthesias in the fifth digit. (E) Radial tunnel syndrome (also known as supinator syndrome) causes inflammation and pain in the origin of the extensor muscles at the lateral epicondyle on resisted extension of the mid- dle finger. The condition may mimic lateral epicon- dylitis, and though the compression site is similar to the compression site in posterior interosseous nerve compression, there is usually no muscle weakness with radial tunnel syndrome.
A 28-year-old woman presents to the emergency
room with a severe orbital headache. What findings would support a diagnosis of spontaneous
internal carotid artery dissection?
A. Complete Horner syndrome with hemisensory
loss, dysphagia, ataxia, and vertigo
B. Complete Horner syndrome with shoulder
and arm pain
C. Complete Horner syndrome with neck pain and
delayed contralateral weakness and sensory
loss
D. Incomplete Horner syndrome with neck pain
and delayed contralateral weakness and sensory loss
E. Mydriasis with contralateral weakness and
sensory loss
D. Incomplete Horner syndrome with neck pain
and delayed contralateral weakness and sensory loss
Spontaneous internal carotid artery dissections usually present with ipsilateral headache. Although difficult to detect clinically, these dissections often present with an incomplete Horner syndrome (oculosympathetic palsy) with ptosis and miosis without anhydrosis. The lack of anhydrosis is because the sympathetic nerves to the facial sweat glands travel on the external carotid artery. Isch- emic events can be a complication of carotid artery dissection. (A) Wallenberg (also known as lateral medullary) syndrome is characterized by disso- ciated sensory loss from vertebral or posterior inferior cerebellar artery occlusion. This results in a complete Horner syndrome, dysphagia, ataxia, vertigo, nystagmus, hoarseness, and loss of pain
and temperature sensation in the ipsilateral face and contralateral body. (B) Pancoast tumors cause Horner syndrome with shoulder and arm pain. (E) Weber syndrome results from a stroke of the ventral midbrain and is characterized by ipsilateral mydriasis and contralateral hemiparesis.
A 15-year-old boy presents with significant discharge from the left ear with severe headache,
facial pain, and diplopia. On exam, he is noted to have a left-sided lateral gaze palsy. What is the patient’s suspected diagnosis?
A. Venous sinus thrombosis
B. Tolosa-Hunt syndrome
C. Raeder paratrigeminal neuralgia
D. Gradenigo syndrome
E. Ramsay-Hunt syndrome
D. Gradenigo syndrome
The classic triad of symptoms in Gradenigo syn- drome is an abducens palsy, retro-orbital pain, and a draining ear from acute otitis media with mas- toiditis and involvement of the petrous apex. The abducens palsy occurs when the infection involves the Dorello canal and ophthalmic branch of the trigeminal nerve, given the anatomic proximity of these structures to the petrous apex. (A) Cranial nerve VI palsies can be a false localizing sign, so intracranial hypertension (sinus thrombosis) must be in the differential. This is not the patient’s most likely diagnosis, however. (B) Tolosa-Hunt syndrome is inflammation of the superior orbital fissure/ cavernous sinus that usually includes painful oph- thalmoplegia, multiple cranial nerve palsies with sparing of the pupil, and dramatic improvement with steroids. (C) Raeder paratrigeminal neural- gia consists of Horner syndrome and trigeminal neuralgia-like pain. (E) Ramsay-Hunt syndrome (also known as Herpes zoster oticus) is reactiva- tion of the varicella zoster virus in the geniculate ganglion, causing otalgia, auricular vesicles, and peripheral facial paralysis.
A patient has a cerebellar lesion causing symptoms including a wide and staggering gait with little impairment of arm or hand movement. What is the likely location of such a lesion?
A. Vestibulocerebellum
B. Cerebellar tonsils
C. Cerebrocerebellum
D. Spinocerebellum
E. Dentate nucleus
D. Spinocerebellum
Common cerebellar syndrome is found in alco- holics and is due to damage to the anterior part of the cerebellar cortex (spinocerebellum). (A) A ves- tibulocerebellum (flocculonodular lobe and adja- cent vermis) lesion impairs the ability to stand upright and maintain gaze direction. Patients have a wide-based stance with small, shuffling move- ments. (B) Cerebellar tonsil pathology often is seen in patients with Chiari 1 malformations. (C) The cerebrocerebellum (lateral cerebellar hemispheres) is involved in highly skilled, learned movements. (E) Lesions interfering with the triangle of Guillain- Mollaret (olivary nucleus, dentate gyrus, and red nucleus) may result in palatal myoclonus.
What is the Wartenberg sign?
A. Wasting of the interossei muscles in the hand
B. Grasping a sheet of paper resulting in extension of the proximal phalanx and flexion of the
distal phalanx
C. Hyperextension at the metacarpophalangeal
joints and flexion at the interphalangeal joints
in digits four, five, and partially three
D. Abduction of fifth digit due to weakness of the
third palmar interosseous muscle
E. Sensory loss over the hypothenar eminence,
fifth finger, and ulnar half of the fourth finger
on the palmar aspect only
D. Abduction of fifth digit due to weakness of the
third palmar interosseous muscle
The Wartenberg sign is abduction of the fifth digit due to paralysis of the adducting palmar in- terosseous muscle and unopposed action of the extensor digiti minimi and digitorum communis muscles (innervated by the radial nerve). (A) Wast- ing of the interossei muscles in the hand is com- mon in ulnar neuropathies. (B) A Froment thumb sign is seen when a patient grasps a sheet of paper resulting in extension of the proximal phalanx and flexion of the distal phalanx. This occurs as the anterior interosseous and flexor pollicis longus substitute for the weakened, ulnar-innervated adductor pollicis. (C) Hyperextension at the meta- carpophalangeal joints and flexion at the interpha- langeal joints in digits four, five, and partially three describes a “claw hand” deformity (also called “main en griffe”), resulting from an ulnar nerve injury. This condition should not be confused with a median nerve injury resulting in a “hand of ben- ediction” deformity. (E) Ulnar nerve compression at the Guyon canal spares the dorsal cutaneous nerve that branches from the ulnar nerve in the forearm proximal to the wrist. Compression at this site also spares the flexor digitorum profundus medial heads.
A 53-year-old man with a heavy smoking history
comes to the office complaining of right upper extremity pain and weakness. Physical examination
reveals a small right pupil and right eye ptosis.
What disease process likely explains this finding?
A. Perineural spread of metastatic disease
B. Tumor compression of the stellate ganglion
C. Cerebral metastatic tumor compressing the
hypothalamus
D. Spinal metastatic disease
B. Tumor compression of the stellate ganglion
The stellate ganglion is a sympathetic ganglion implicated in some pain syndromes, and lesions of this ganglion can cause a Horner syndrome. Iatro- genic injuries sometimes occur during injections or blocks for complex regional pain syndrome. A Pancoast tumor also may compress the nerve roots or trunks of the brachial plexus to cause upper extremity weakness.
An 8-year-old girl is brought to the emergency
room by her grandmother after 1 week of fever and
lethargy and a 2-day history of progressive rightsided weakness. A head CT is normal, and an
MRI with FLAIR sequence of the brain and spine
demonstrates a subtle abnormality within the
subcortical white matter. Cerebrospinal fluid
studies show an elevated white blood cell and
protein count. Further studies are pending. What
is the most likely diagnosis?
A. Juvenile-onset multiple sclerosis
B. Progressive multifocal leukoencephalopathy
C. Adrenoleukodystrophy
D. Acute disseminated encephalomyelitis
D. Acute disseminated encephalomyelitis
Acute disseminated encephalomyelitis (ADEM) is the most common white matter disease in chil- dren. It typically follows an illness or vaccination and is differentiated from multiple sclerosis because multiple sclerosis has a multiphasic presentation. The first-line treatment for ADEM is intravenous steroids followed by a prednisone taper. Cases that do not respond to steroids may require intravenous immunoglobulins.
Fill in the blanks.
Korsakoff psychosis results from deficiency of
__________ (nutrient), is __________ (reversible/irreversible), and affects the __________ (anatomic
structure).
A. Folate; irreversible; medial dorsal thalamic
nuclei
B. Folate; reversible; mammillary bodies
C. Thiamine; irreversible; medial dorsal thalamic
nuclei
D. Thiamine; reversible; mammillary bodies
E. Thiamine; irreversible; cerebellum
C. Thiamine; irreversible; medial dorsal thalamic
nuclei
Korsakoff psychosis/syndrome is present in 80% of individuals who survive the preceding Wernicke encephalopathy, which is triggered by a thiamine deficiency. Korsakoff syndrome is irreversible. The classic triad for Wernicke encephalopathy is encephalopathy, ophthalmoplegia, and ataxia. With either condition, MRI FLAIR sequences typically demonstrate signal in the medial thalamus, floor of the fourth ventricle, and periaqueductal gray matter of the midbrain.
The nurse calls you to evaluate a recently admitted
patient with Guillain-Barré syndrome. The patient
initially had only lower extremity weakness but
now has a weak quality of voice and is taking shallow, rapid breaths. What is the next most appropriate step in this patient’s management?
A. Initiate plasmapheresis.
B. Give intravenous dexamethasone.
C. Intubate the patient
D. Give intravenous immunoglobulin.
C. Intubate the patient
This question emphasizes the importance of the “ABCs” (airway, breathing, and circulation) in emer- gency situations. Although quick initiation of treat- ment for Guillain-Barré syndrome is important, the patient is showing clinical signs of impending respiratory failure, making intubation the correct option.
A 72-year-old woman was admitted to the hospital
for severe vertigo of 1 day’s duration. She subsequently developed nausea, vomiting, dysphagia,
hoarseness, and loss of left facial pain sensation.
The patient is alert and oriented to time, space, and
person. She has no motor deficits but does have
ptosis on the left and clumsiness of the left arm.
The patient also has decreased proprioception in
the left foot and loss of pain and temperature sensation on the right side. The patient’s MRI demonstrates an ischemic stroke. What is the most likely
localization of the stroke?
A. Right lateral medulla
B. Left lateral medulla
C. Right medial medulla
D. Left medial medulla
E. Right and left lateral medulla
B. Left lateral medulla
Lateral medullary syndrome (also known as Wal- lenberg syndrome) is due to infarction of the lat- eral medulla. Structures in this region include the nucleus and descending tract of the fifth cranial nerve, nucleus ambiguus, lateral spinothalamic tracts, inferior cerebellar peduncle, and descending sympathetic fibers of the vagus and glossopharyn- geal nerves. Patients with Wallenberg syndrome have a classic constellation of symptoms includ- ing (1) ipsilateral Horner syndrome, (2) ipsilateral ataxia, (3) ipsilateral loss of facial pain and tem- perature perception, (4) ipsilateral loss of the cor- neal reflex, (5) ipsilateral impairment of corneal reflexes, (6) contralateral loss of pain and tempera- ture sensation, (7) dysphagia, and (8) dysphonia.
An 81-year-old man with a history of hip replacement 3 weeks ago complicated by a mild myocardial infarction is brought to the hospital with an
acute-onset middle cerebral artery stroke. The
patient has been maintained on warfarin, and the
INR is 2.3. The platelet count is 120,000. In this
patient, what is an absolute contraindication to
thrombolysis?
A. Age over 80 years
B. Hip replacement within 3 weeks of
presentation
C. Recent history of myocardial infarction
D. INR of 2.3
E. Platelets count of 120,000
D. INR of 2.3
An INR over 1.7 is an absolute contraindication to thrombolysis. Other absolute contraindications to thrombolysis include (1) uncertainty about time of stroke onset (e.g., patients awakening from sleep); (2) coma or severe obtundation with fixed eye deviation and complete hemiplegia; (3) hyper- tension with a systolic blood pressure at least 185 mm Hg or a diastolic blood pressure over 110 mm Hg on repeated measures (if reversed, a patient can be treated); (4) clinical presentation suggestive of subarachnoid hemorrhage, even if the CT scan is unremarkable; (5) presumed septic embolus; (6) patient having received a heparin medication within the last 48 hours, with an elevated activated
prothrombin time (APTT) or with a known heredi- tary or acquired hemorrhagic diathesis; (7) known advanced liver disease, advanced right heart fail- ure, or coagulopathy disorder with an INR over 1.5; (8) platelet count less than 100,000/μL; and (9) serum glucose less than 2.8 mmol/L or greater than 22.0 mmol/L. (A–C) Age over 80 years, major sur- gery within 2 weeks of presentation, hip replace- ment within 3 weeks of presentation, and recent myocardial infarction all are relative contraindica- tions to thrombolysis.
A 3-year-old boy who was previously healthy
develops a red, scaly rash over his face, neck, hand,
and legs. He then starts having emotional liability
and episodic cerebellar ataxia, and eventually experiences developmental delay. After being worked
up, he is treated with high doses of nicotinamide.
What is the patient’s diagnosis?
A. Hartnup disease
B. Phenylketonuria
C. Homocystinuria
D. G6PD deficiency
E. Tetrahydrobiopterin deficiency
A. Hartnup disease
Hartnup disease (also known as pellagra-like der- matosis) is an autosomal recessive disease affecting the absorption of nonpolar amino acids, particu- larly tryptophan, which is a precursor to serotonin, melatonin, and niacin. Niacin is a precursor to nicotinamide, which is a necessary component of NAD. Clinically, the disease is characterized by a childhood presentation, with symptoms ranging from failure to thrive, photosensitivity, intermit- tent ataxia, nystagmus, and tremor. Supplemen- tation with high doses of nicotinamide usually is sufficient to treat the disease. (B) Phenylketonuria is caused by absent phenylalanine hydroxylase. It usually is treated with a strict phenylalanine- restricted diet. If untreated, patients suffer intel- lectual disability and seizures and eventually could die. (C) Homocystinuria leads to multisystemic disorders of connective tissue, muscles, and the central nervous and cardiovascular systems. There is no specific cure for homocystinuria; however, many people are treated with high doses of vita- min B6. (D) G6PD deficiency does not affect the central nervous system. Treatment is by prevent- ing exposure to drugs and foods that cause hemo- lysis. (E) Tetrahydrobiopterin deficiency is a rare metabolic disorder that increases the blood levels of phenylalanine, which leads to low muscle tone and possible difficulty swallowing, seizures, pro- gressive problems with development, and an inability to control body temperature. Treatment consists of tetrahydrobiopterin supplementation and a low phenylalanine diet.
A 48-year-old woman presents with a sudden
onset of blurred vision and pain on movement of
her right eye. She reports that 2 years ago, she had
loss of sensation in the hands that progressed over
a couple of weeks to motor involvement limiting
her ability to write with the left hand. At the time,
she was afraid to seek medical attention. What is
the most likely diagnosis?
A. Multiple sclerosis
B. Guillain-Barré syndrome
C. Transient ischemic attack
D. Myasthenia gravis
E. Amyotrophic lateral sclerosis
A. Multiple sclerosis
Multiple sclerosis is the most common auto- immune disorder affecting the central nervous system, and patients can have a wide range of neu- rologic symptoms. In this clinical vignette, the pa- tient has symptoms of optic neuritis, which affects
up to 50% of multiple sclerosis patients. (B) Guillain- Barré syndrome is characterized by a rapid-onset weakness of the limbs as a result of an acute poly- neuropathy affecting the peripheral nervous system. (C) Transient ischemic attacks are characterized by focal neurologic deficits that resolve within 24 hours. (D) Myasthenia gravis is an autoimmune or congenital neuromuscular disease character- ized by fluctuating muscle weakens and fatigue. Extraocular muscles often are involved. (E) Amy- otrophic lateral sclerosis is characterized by grad- ually worsening weakness and stiff muscles with fasciculations.
A 30-year-old man with a history of homocystinuria develops a headache followed by hemiparesis
and focal epilepsy. He is brought to the emergency
room for evaluation. What is the most sensitive
imaging modality to detect this patient disease?
A. Noncontrast CT scan
B. T2-weighted MRI
C. Angiogram
D. Whole body PET CT
E. Perfusion-weighted imaging
C. Angiogram
An angiogram is the most sensitive modality to diagnose sagittal sinus thrombosis. The presence of headache, hemiparesis, and focal epilepsy in a relatively young patient is indicative of sagittal sinus thrombosis. The likelihood of having the pathology is much higher in patients with a his- tory of hypercoagulable disorders such as homocystinuria.
When examining a man, you notice that he has
difficulty maintaining balance when his feet are
together and his eyes are closed. He also struggles
to rub accurately the heel of one foot along the shin
of the opposite leg. What system is most likely
malfunctioning?
A. Vision
B. Proprioception
C. Vestibular system
D. Cerebellum
B. Proprioception
The tests described are the Romberg and heel- shin tests. Both of these test proprioception. The Romberg test combines vision, proprioception, and vestibular function. The heel-shin test assesses vision, proprioception, and cerebellar function.
A retired boxer with a history of more than 20
bouts comes to your office for evaluation of
“abnormal behavior” reported by the family. On
exam, the patient has a resting tremor, decreased
coordination, poor attention span, no focal weakness, and subtle paranoia upon questioning. You
suspect chronic traumatic encephalopathy. What
would you expect to find on pathological examination of his cerebral tissue?
A. Normal cerebral architecture
B. Loss of pigmentation in the substantia nigra
C. Caudate atrophy
D. Deposition of β-amyloid plaques
D. Deposition of β-amyloid plaques
Chronic traumatic encephalopathy often is described in retired boxers, and the risk of devel- oping this condition increases with career length. Patients develop motor, cognitive, and psychiatric disturbances. Pathological examination reveals cerebral and cerebellar atrophy, neurofibrillary tangles, and β-amyloid deposition.
What is the most effective mean of aborting a cluster headache?
A. Inhaled 100% O2
B. Sublingual nitroglycerin
C. Ergotamine
D. Methysergide
E. Intravenous nonsteroidal anti-inflammatory
agents
A. Inhaled 100% O2
Inhaled 100% O2 is the best treatment to abort a cluster headache within minutes. (B) Sublingual nitroglycerin is not recommended for the treat- ment of headaches. (C) Ergotamine can help abort some vascular type headaches but is not efficient in aborting cluster headaches. (D) Methysergide is the classic drug used to prevent cluster headaches, but it is no longer used due to retroperitoneal and retropulmonary fibrosis.
A 4-month-old boy with psychomotor retardation
develops repetitive, generalized limb extension and
neck flexion spasms that occur more than 10 times
daily. These episodes are associated with altered
consciousness. Electroencephalographic evaluation
demonstrates high-voltage polyspike and slow
wave discharges between spasms and suppression
of these bursts during the spasms. What is the
patient’s most likely diagnosis?
A. Absence seizures
B. West syndrome
C. Epilepsia partialis continua
D. Complex partial seizures
E. Juvenile myoclonic seizures
B. West syndrome
West syndrome is a generalized seizure disor- der of infants characterized by a triad of recur- rent spasms, hypsarrhythmia, and developmental regression. Hypsarrhythmias are abnormal inter- ictal patterns consisting of high amplitude and irregular waves and spikes in a background of cha- otic and disorganized activity. (A) Absence seizures are characterized by a brief loss of consciousness without a notable postictal phase. (C) Epilepsia partialis continua is a rare seizure disorder in which the patient experiences recurrent focal motor epileptic seizures that recur every few sec- onds or minutes for long periods of time (months or years). (D) Complex partial seizures are sei- zures that are associated with unilateral cerebral hemisphere involvement and cause impairment of awareness or responsiveness. (E) Juvenile myoc- lonic seizures usually begin around puberty and tend to have a genetic basis. These seizures can be stimulus selective.
A 27-year-old man is involved in a motor vehicle
collision. The patient is brought to the emergency
room and stabilized, and imaging demonstrates a
lower cervical spinal cord injury. On exam, the
patient is hypotensive and lethargic with minimal
movements of the upper extremities. You suspect
spinal shock and initiate pressor support. Spinal
shock occurs when there are injuries to the spinal
cord above what level, and the hypotension
observed is due to interruption of what element
of the nervous system?
A. T6; sympathetics
B. T1; sympathetics
C. T6; parasympathetics
D. T1; parasympathetics
B. T1; sympathetics
Spinal shock is characterized by hypotension (systolic blood pressure less than 80 mm Hg) fol- lowing a spinal cord injury. It is mediated by an injury to the spinal cord above T1, which causes an interruption in the sympathetic fibers. This leads to a loss of vascular tone causing hypotension. The loss of sympathetics leads to an unopposed para- sympathetic tone, which causes the bradycardia seen in spinal shock.
When looking at an electromyogram, you notice
that the motor unit potentials are demonstrating
decreased amplitudes and durations. What process(es) exhibit these changes?
A. Denervation
B. Reinnervation
C. Myopathy and neuromuscular junction disease
D. Myopathy but not neuromuscular junction
disease
C. Myopathy and neuromuscular junction disease
Myopathy and neuromuscular junction disease both demonstrate decreased amplitudes and dura- tions of motor unit potentials. (A, B) Denervation and reinnervation exhibit decreased motor unit po- tential amplitudes but increased durations. “Giant units” may form during reinnervation, and polypha- sic potentials may be seen during reinnervation with myopathy or neuromuscular junction disease.
The pathology of acute disseminated encephalomyelitis in humans is similar to an animal model of
experimental allergic encephalomyelitis. How is
this model typically developed?
A. Injection of central nervous system proteins
into animal brain parenchyma
B. Injection of whole blood into the subarachnoid space of an animal
C. Injection of penicillin into animal brain
parenchyma
D. Injection of white blood cell extracts into the
subarachnoid space of an animal
E. Injection of prions into animal brain
parenchyma
A. Injection of central nervous system proteins
into animal brain parenchyma
Experimental autoimmune encephalomyelitis is an animal model of brain inflammation. It is an inflammatory demyelinating disease of the central nervous system that can be induced by injecting central nervous system proteins, such as spinal
cord homogenate and purified myelin, into animal brain parenchyma.
What is classically described as the cause of an
immediate coma in a patient after a head injury
without evidence of an intracranial mass or
ischemia?
A. Severe concussion
B. Diffuse axonal injury
C. Dural sinus thrombosis
D. Atlantoaxial dislocation
B. Diffuse axonal injury
Diffuse axonal injury is a primary lesion of a rotational acceleration/deceleration head injury, which can be associated with petechial hemor- rhages in the dorsolateral rostral brain stem and corpus callosum
A 13-year-old boy presents to his physician because
his parents are concerned about an enlarging
abdomen and increasing fatigue over the course
of 2 months. The patient’s father is noted to have
slurred speech and difficulty with balance as he
enters the exam room. On physical exam, spider
nevi are noted on the boy’s chest, and there are
some corneal abnormalities in the eyes. What is
the best treatment for the patient’s condition?
A. Dimercaprol
B. Penicillamine
C. L-dopa
D. Interferon
E. Splenectomy
B. Penicillamine
This patient has Wilson disease, a rare disorder of copper metabolism. Wilson disease also is known as hepatolenticular degeneration and is inherited in an autosomal recessive pattern. Copper accumulates in tissues including the basal ganglia, which leads to parkinsonism as well as cognitive deterioration and clumsiness. Patients can have Kayser-Fleischer rings, which are pathognomonic copper deposits in the cornea. Penicillamine binds accumulated copper and eliminates it in the urine.
A patient is referred for nervus intermedius neuralgia. Based on this diagnosis, what clinical findings are expected?
A. Paroxysmal, lancinating pain in the lower one
third of the face
B. Loss of taste to the anterior two thirds of the
ipsilateral tongue
C. Periorbital vesicular rash, conjunctivitis, keratitis, and uveitis with involvement of the tip of
the nose
D. Paroxysmal, lancinating pain in the upper one
third of the face
E. Paroxysmal, lancinating pain in the depth of
the ear with loss of taste in the anterior two
thirds of the tongue with possible increased
salivation
E. Paroxysmal, lancinating pain in the depth of
the ear with loss of taste in the anterior two
thirds of the tongue with possible increased
salivation
The diagnosis of nervus intermedius (genicu- late) neuralgia is rare. The nerve carries general visceral efferents from the superior salivatory nucleus and passes through the geniculate ganglion without synapsing before heading to the pterygo- palatine ganglion and lacrimal gland through the greater petrosal nerve. The nervus intermedius also carries special visceral afferents from the chorda tympani to the nucleus solitarius and general spe- cial afferents from the inner ear, middle ear, and part of the pinna. (A) Paroxysmal, lancinating pain in the lower one third of the face can be seen in trigeminal neuralgia. (B) The chorda tympani relays taste from the anterior two thirds of the ipsilateral tongue. (C) Herpes zoster ophthalmicus is charac- terized by a periorbital vesicular rash, conjuncti- vitis, keratitis, and uveitis with involvement of the tip of the nose.
