MCQs In Pediatric Neurology-Part II

Q1 :

You are conducting a health supervision visit for a 5-month-old infant who had been in the neonatal intensive care unit. She feeds well and is thriving. The baby was born at 29 weeks' gestation, and head ultrasonography at 6 weeks of age had documented periventricular leukomalacia. Physical examination reveals brisk reflexes, ankle clonus, and bilateral Babinski sign.

Of the following, the type of cerebral palsy for which this infant is MOST at risk is:

A. ataxic

B. athetoid

C. spastic diplegic

D. spastic hemiplegic

E.  spastic quadriplegic

Answer

C

Spastic diplegia is a form of cerebral palsy that is marked by bilateral spasticity of the lower extremities, which may be mild or severe, and little deficit in the upper extremities. Scissoring of the lower extremities may be present when the child is suspended vertically. In mild or moderate cases, walking is delayed, and the child may walk on tiptoes. In some instances, the feet are in an equinovarus posture. This injury pattern arises commonly in preterm infants from ischemia to the vascular border zone around the cerebral ventricles and resultant periventricular leukomalacia, as reported for the infant in the vignette. 

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Q 2

An otherwise healthy 1-year-old girl has had several episodes in which she becomes cyanotic and loses consciousness after crying. She is brought to the office 1 hour after an episode. She is alert, takes a few steps, and says "mama" to her mother. The physical examination findings are normal.

Of the following, the MOST appropriate next step in the evaluation is to:

A.  admit her to the hospital

B.  order computed tomography of the head

C.  order electrocardiography

D.  order electroencephalography

E.   reassure the parents

Answer

E

The child described in the vignette presents with breath-holding spells, a condition that occurs in 4% to 5% of healthy children. Because breath-holding spells are benign, reassuring the parents is the most appropriate action. These reflexive events are provoked by anger, frustration, pain, or fear. The child begins crying, then stops in full exhalation at which time a pale or cyanotic color change is noted. A simple spell ends at this point, but a complex spell persists until the child loses consciousness. Occasionally, the child will experience a hypoxic seizure with postictal changes. Most spells start between the ages of 6 and 18 months and resolve by 6 years of age.

            There are two types of breath-holding spells: cyanotic and pallid. Cyanotic spells are due to abnormal respiratory regulation, with color change due to oxygen desaturation during apnea. Pallid spells are mediated by an overactive vagal response that leads to bradycardia or asystole.

            The differential diagnosis of breath-holding includes seizure, cardiac arrhythmia, and gastroesophageal reflux. These diagnoses usually are excluded easily with a complete history and physical examination. An association between anemia and breath-holding spells has been noted in some patients, with treatment of the anemia causing cessation of spells, but a causal connection has not been confirmed.

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Q 3

During a health supervision visit of a 6-month-old boy, you note a head circumference of 46 cm (98th percentile). The anterior fontanelle is open and flat. Findings on the remainder of the physical examination are normal.

Of the following, the MOST appropriate action at this time is to:

A. measure parental head circumference

B.  obtain computed tomography of the head

C.  obtain head ultrasonography

D.   refer the boy to an ophthalmologist for slitlamp examination

E.   wait until the next examination to measure interval growth

Answer

A

A head circumference greater than 2 standard deviations above the mean is termed macrocephaly, although some use the term megalencephaly. The term refers only to the size of the cranium; it does not describe the condition of the brain. When macrocephaly is accompanied by otherwise normal findings on physical examination and development, as for the boy in the vignette, it usually is benign and frequently familial. Therefore, measurement of the parental head circumferences can be useful; the presence of a large cranium in a parent provides further evidence of a benign condition.

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Q 4:

You are evaluating a 4-month-old boy for complaints of fussiness and decreased feeding for the past 24 hours. You have not previously seen the patient, but the mother states that he has had no previous illnesses, did not receive his immunizations, and is not taking any medications. On physical examination, the boy has a temperature of 37.6°C, a heart rate of 160 beats/min, and a respiratory rate of 55 breaths/min. Physical examination findings are remarkable only for a lethargic infant who has a full anterior fontanelle and widened cranial sutures.

Of the following, the MOST appropriate initial test is

A. computed tomography of the head

B. electroencephalogram

C. lumbar puncture

D. plain radiograph of the skull

E. urine toxicology screen

Answer

A

The infant described in the vignette exhibits several signs consistent with increased intracranial pressure, including lethargy, a full anterior fontanelle, widened sutures, and elevations of the heart and respiratory rates. Computed tomography scan or magnetic resonance imaging (MRI) of the head is the first priority in evaluating suspected increased intracranial pressure after initial stabilization. There is no indication for a plain radiograph of the skull in this patient. Computed tomography—although it delivers ionizing radiation and provides less anatomical detail when compared to MRI—is often used in the acute setting because of its greater availability, speed in determining potential need for surgical intervention, and value in narrowing the diagnosis and initiating treatment. It is important to remember that the presence of increased cranial pressure cannot be accurately determined on a computed tomography study unless there is evidence of effacement of the basilar cisterns or lateral ventricles.

Lumbar puncture is indicated when infectious causes are of concern. However, for the infant in the vignette, the absence of fever and other symptoms and signs consistent with infection do not support the need for lumbar puncture. In addition, lumbar puncture should be deferred in the presence of significant neurologic findings that might be consistent with impending brainstem herniation.  Electroencephalography or urine toxicology might be indicated in a child who presents with a change in mental status, but the presentation of the infant in the vignette makes these tests less likely to be informative.

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Q 5:

A 2-year-old girl who has developmental delay presents to urgent care after a cyanotic episode at daycare. She was noted to have a look of fear and then confusion associated with slow breathing, a choking sound, and diminished awareness. Afterward, she seemed “out of it” and unlike herself. The parents believe that this is similar to several previous episodes, although the duration today was longer. Physical examination reveals that the child has small growth parameters, including head circumference. She sits but does not stand, and she has no language and poor eye contact. She has truncal unsteadiness and brings her hands to her mouth frequently.

Of the following, the MOST likely diagnosis is

A. acute cerebellar ataxia

B. ataxia telangiectasia

C. Joubert syndrome

D. Niemann-Pick disease type C

E. Rett syndrome

Answer

E

The girl in the vignette presented for medical attention after experiencing a seizure. According to her parents, it appears that several previous, unprovoked seizures have occurred, which is consistent with a diagnosis of epilepsy. In girls who have small growth parameters, developmental delay, truncal unsteadiness, and stereotypic midline hand behaviors, Rett syndrome should be considered. Rett syndrome is an X-linked dominant disorder caused most often by a mutation in the MECP2 gene. The diagnosis of Rett syndrome is made clinically and is the entity most likely responsible for the symptoms and signs exhibited by the girl in the vignette.

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Q 6


A 10-year-old boy presents with leg weakness that has progressed over 24 hours, bladder and
bowel incontinence, and back pain. There is no history of trauma. On physical examination, leg
reflexes are diminished, and there is numbness in the legs and lower trunk. Rectal examination
demonstrates decreased tone. Sensory examination shows absent pinprick sensation below T6.
Of the following, the MOST appropriate initial diagnostic test is

A. brain magnetic resonance imaging with contrast
B. electromyography of the legs
C. lumbar puncture
D. nerve conduction velocities
E. spine magnetic resonance imaging with contrast

Answer

E


'The child described in the vignette has subacute rapidly progressive weakness and back pain
serious findings that require emergent diagnostic evaluation and management that includes
imaging in an attempt to localize the problem to the brain, brainstem, spinal cord, nerve root,
nerve, neuromuscular junction, or muscle. The reported sensory, motor, bowel and bladder
symptoms are explained best by a lesion in the spinal cord. Such lesions can present in children
abruptly, subacutely, or insidiously. Respiratory failure can occur due to high cervical spine
lesions affecting the phrenic nerve to diaphragm function, but are not likely in this case.
Autonomic difficulties other than bowel and bladder incontinence also are common in chronic
spinal cord injuries, but again are unlikely in this setting. Failure to diagnose treatable spinal cord
lesions can result in permanent neurologic deficits. Magnetic resonance imaging (MRI) of the
thoracic spine with contrast has the highest diagnostic yield in the acute presentation

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Q 7


A 12-year-old girl in your practice had been born preterm and presented in early childhood with
developmental delay. She was diagnosed with cerebral palsy and has been given physical,
occupational, and speech therapy. Magnetic resonance imaging at age 3 years showed white
matter volume loss, particularly adjacent to the ventricles. The parents are concerned their
daughter’s condition may be degenerating because she has fallen progressively further behind
her peers, and she has become increasingly anxious and oppositional. She has not developed
seizures. Her recent special education re-evaluation at school revealed verbal and performance
intelligence quotients in the 70s, unchanged from 3 years ago. On physical examination, you
note dolichocephaly, hyperreflexia at the knees, and two beats of clonus at each ankle.

Of the following, the MOST appropriate next step is

A. follow-up magnetic resonance imaging
B. measurement of urine organic acids
C. referral for behavioral therapy
D. referral to genetics
E. sleep-deprived electroencephalography

Answer:



The child described in the vignette has cerebral palsy, a static encephalopathy due to her
preterm birth, and a typical constellation of motor, cognitive, and mood problems. Her physical
examination findings are classic for cerebral palsy due to prematurity, with narrowing of the head
due to brain volume loss and upper motor neuron signs affecting predominantly the legs.


Children who have stable, nonprogressive cognitive, motor, and behavioral disabilities
may appear to their caregivers to be deteriorating due to the emergence of new mood problems
such as anxiety or because academic achievement has leveled off at a time when the
achievement of the child’s peers is accelerating. The most important intervention at this point is
referral for behavioral therapy. Both the parents and the child may need support as the child
moves into adolescence, and the child may benefit from therapy to cope with anxiety.

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Q 8



You care for a 3-year-old girl who was born with spina bifida. The child is otherwise normally
formed and is developmentally appropriate with respect to her social, fine motor, and language
skills. During a routine visit, her mother tells you that she is contemplating another pregnancy.
You mention the important role of folic acid in the prevention of neural tube defects, and you
recommend that she discuss this with her obstetrician.
Of the following, the recommendation, implemented before and during pregnancy, that should
have the GREATEST impact on reducing this woman’s risk for having a future child affected with
spina bifida is to

A. consume only grains and cereals that are folic acid-fortified
B. increase consumption of folic acid-rich leafy green vegetables
C. measure the woman’s serum folic acid level and supplement accordingly
D. prescribe oral folic acid 0.4 mg daily
E. prescribe oral folic acid 4 mg daily

Answer

E


For women who have had a previous pregnancy affected by an NTD, the CDC
recommends daily consumption of 4 mg (4,000 mcg) of folic acid daily from the time they begin
trying to get pregnant through the first trimester of pregnancy. These same women should
consume 0.4 mg of folic acid daily when not trying to become pregnant.
Because the 4-mg dose is ten times higher than that recommended for women at average
risk, and because folic acid supplementation via fortified grains has been shown not to be as
successful in reducing NTDs as folic acid tablets, the latter are recommended for the mother
described in the vignette. Measuring a woman’s serum folic acid concentration does not reliably
determine her need over an entire pregnancy. Leafy green vegetables are rich in folic acid, and
their consumption is encouraged, but the amount any woman consumes is uncertain.