Pathophysiology: Chapter 20: Alterations of Neurologic Function in Children

Question 1

The neural groove closes dorsally during which week of gestational life?

a. Second
b. Fourth
c. Eighth
d. Twelfth

Answer 1

ANS: B
During the fourth gestational week, the neural groove deepens, its folds develop laterally,
and it closes dorsally to form the neural tube, epithelial tissue that ultimately becomes the
central nervous system (CNS). The second week is too early, and the other options
represent times periods after the groove closes.

Question 2

Which nutritional deficiency in a pregnant woman is associated with neural tube defect
(NTD)?
a. Iron 
b. Vitamin C
c. Zinc 
d. Folate

Answer 2

ANS: D
Maternal folate deficiency is associated with NTDs, but the specific mechanism that
relates to how folate supplements prevent these anomalies is unknown. The other options
are not thought to cause such a defect.

Question 3

Which defect of neural tube closure is most common?

a. Anterior
b. Posterior
c. Lateral
d. Midline

Answer 3

ANS: B

Posterior defects are most common. The other options are not the most common.

Question 4

What is the anomaly in which the soft bony component of the skull and much of the brain
is missing?
a. Anencephaly 
b. Myelodysplasia
c. Cranial meningocele 
d. Hydrocephaly

Answer 4

ANS: A
Anencephaly is an anomaly in which the soft, bony component of the skull and much of
the brain are missing. The other options do not represent this condition.

Question 5

The most common cause of obstructive hydrocephalus in infants is:

a. Obstructed arachnoid villi
b. Stenosis of the aqueduct of Sylvius
c. Excessive production of cerebrospinal fluid
d. Impaired cerebrospinal fluid circulation in the subarachnoid space

Answer 5

ANS: B
Congenital aqueduct stenosis most commonly causes obstructive hydrocephalus. The other
options do not represent the most common cause of this condition.

Question 6

What is the term for a herniation or protrusion of brain and meninges through a defect in
the skull?
a. Encephalocele 
b. Meningocele
c. Arachnoidocele 
d. Cephacephalocele

Answer 6

ANS: A
Encephalocele refers to a herniation or protrusion of brain and meninges through a defect
in the skull, resulting in a saclike structure. The other terms are not used to describe an
encephalocele.

Question 7

What is the result of a Chiari type II malformation associated with a myelomeningocele?

a. Upward displacement of the cerebellum into the diencephalon
b. Motor and sensory lesions below the level of the myelomeningocele
c. Downward displacement of the cerebellum, brainstem, and fourth ventricle
d. Generalized cerebral edema and hydrocephalus

Answer 7

ANS: C
One serious, potentially life-threatening problem associated with myelomeningocele is the
Chiari type II malformation. This deformity involves the downward displacement of the
cerebellum, cerebellar tonsils, brainstem, and fourth ventricle. The other options do not
appropriately describe the pathologic characteristics resulting from a Chiari type II
malformation.

Question 8

Prompt surgical repair of a myelomeningocele is critical to best prevent:

a. Infection
b. Paralysis
c. Mental retardation
d. Additional nervous system damage

Answer 8

ANS: D
Until the myelomeningocele is surgically closed, cerebrospinal fluid (CSF) may
accumulate, resulting in further dilation and enlargement of the sac, which may risk more
damage to the nervous system. The other options are included as possible damage caused
by the increased leaking of CSF.

Question 9

Which body system is the largest site for human immunodeficiency virus (HIV) infection
in infants and children?
a. Central nervous system 
b. Gastrointestinal system
c. Integumentary system
d. Musculoskeletal system

Answer 9

ANS: A
A particularly vulnerable site of HIV-1 infection in infants and children is the CNS. This
vulnerability cannot be proven regarding the other provided options.

Question 10

An infant diagnosed with hydrocephalus is observed to demonstrate:

a. Shrunken ventricles
b. Bulging fontanels
c. Retarded head growth
d. Decreased production of cerebrospinal fluid

Answer 10

ANS: B
During the early weeks of life, the head begins to grow at an abnormal rate. Significant
dilation of the ventricles may occur before an abnormal increase in head growth develops.
The fontanels enlarge and become full and bulging. Cerebrospinal fluid production does
not decrease.

Question 11

Gait disturbances and instability are characteristic of which form of cerebral palsy?

a. Spastic
b. Dyskinetic
c. Ataxic
d. Biochemical

Answer 11

ANS: C
Ataxic cerebral palsy causes damage to the cerebellum and exhibits gait disturbances and
instability. This description is not accurate of the other options.

Question 12

Children with phenylketonuria (PKU) are unable to synthesize:

a. Essential amino acid, phenylalanine, to tyrosine
b. Renin, erythropoietin, and antidiuretic hormone
c. Aldosterone, cortisol, and androgens
d. Neurotransmitters gamma-aminobutyric acid (GABA) and acetylcholine

Answer 12

ANS: A
PKU is an inborn error of metabolism characterized by the inability of the body to convert
the essential amino acid, phenylalanine, to tyrosine. PKU does not affect synthesis of the
other options.

Question 13

Benign febrile seizures are characterized by:

a. A temperature lower than 39° C
b. Respiratory or ear infections
c. Onset after the fifth year of life
d. Episodes lasting 30 minutes or longer

Answer 13

ANS: B
An acute respiratory or ear infection is usually present. Simple febrile seizures are rare in
infants before 9 months of age or in children older than 5 years of age. The convulsion
occurs with a rise in temperature higher than 39° C (102.2 °F). The convulsion is short (15
minutes or less).

Question 14

What is the most common general symptom of a localized childhood brain tumor?

a. Poor bonding
b. Increased intracranial pressure
c. Delayed extinction of newborn reflexes
d. Failure to thrive

Answer 14

ANS: B
Symptoms of brain tumors may be generalized or localized. The most common general
symptom is increased intracranial pressure, which may cause headaches, irritability,
vomiting, somnolence, and bulging of fontanels. The remaining options are not the most
common symptom of a localized childhood tumor.

Question 15

The tonic neck reflex observed in a newborn should no longer be obtainable by:

a. 2 years
b. 1 year
c. 10 months
d. 5 months

Answer 15

ANS: D

The tonic neck reflex should be unobtainable by 5 months of age.

Question 16

What term is used to describe a hernial protrusion of a saclike cyst that contains meninges,
spinal fluid, and a portion of the spinal cord through a defect in a posterior arch of a
vertebra?
a. Encephalocele
b. Meningocele
c. Spina bifida occulta
d. Myelomeningocele

Answer 16

ANS: D
Myelomeningocele is a hernial protrusion of a saclike cyst containing meninges, spinal
fluid, and a portion of the spinal cord with its nerves through a defect in the posterior arch
of a vertebra. The remaining options are not appropriate terms to identity the described
condition.

Question 17

What test is performed on amniotic fluid and maternal blood to test for neural tube defect?

a. Total protein
b. Culture
c. alpha-fetoprotein
d. C-reactive protein

Answer 17

ANS: C
The presence of a neural tube defect (NTD) may result in an elevated amniotic fluid
alpha-fetoprotein (AFP) level and subsequent maternal serum AFP levels. The tests presented
in the remaining options are not used to diagnose an NTD.

Question 18

The clinical manifestations of dyskinetic cerebral palsy include:

a. Increased muscle tone and prolonged primitive reflexes
b. Exaggerated deep tendon reflexes, clonus, and rigidity of extremities
c. Scoliosis, contractures, and stiffness of trunk muscles
d. Jerky uncontrolled and abrupt fine musculoskeletal movements

Answer 18

ANS: D
Dyskinetic cerebral palsy is associated with extreme difficulty in fine motor coordination
and purposeful movements. Movements are jerky, uncontrolled, and abrupt, resulting from
injury to the basal ganglia or thalamus. The symptoms presented by the other options are
not associated with this form of cerebral palsy.

Question 19

Which musculoskeletal deformities are associated with myelomeningocele? (Select all that

apply. )
a. Extra digits on feet
b. Clubfoot
c. Dislocation of the hips
d. Scoliosis
e. Kyphosis

Answer 19

ANS: B, C, D, E
Several musculoskeletal deformities are related to myelomeningocele, including clubfoot,
dislocation of hip or hips, and poor spinal alignment. Spinal deformities, such as scoliosis
and kyphosis, are also common. Extra digits are not associated with myelomeningocele.

Question 20

True microcephaly can be caused by: (Select all that apply.)

a. Autosomal gene alterations
b. Prenatal physical abuse of the mother
c. X-linked gene alterations
d. Toxic-induced chromosomal defects
e. Maternal anorexia

Answer 20

ANS: A, C, D
Genetic alterations, including autosomal dominant, autosomal recessive or X-linked genes,
or various chromosomal abnormalities can cause true (primary) microcephaly (present at
birth). Environmental causes include toxin exposure during the period of induction and
major cell migration. Radiation, intrauterine infection, or chemical exposure may be the
initiating factor. Secondary microcephaly (developing postnatally) is associated with a
variety of causes including infection, trauma, metabolic disorders, maternal anorexia
experienced during the third trimester of pregnancy, and the presence of other genetic
syndromes.

Question 21

Which statements regarding the term myelodysplasia are true? (Select all that apply.)
a. Myelodysplasia is used to define a defect in the formation of the spinal cord.
b. It can be used to refer to brain anomalies involving missing brain tissue.
c. Myelodysplasia correctly includes encephaloceles.
d. It is used to describe a herniation of brain and meninges through a defect in the
skull.
e. Myelodysplasia can be used to refer to a form of spina bifida.

Answer 21

ANS: A, E
Although myelodysplasia is defined as a defect in the formation of the spinal cord, the
term is also used to refer to anomalies of both the vertebral column and the spinal cord.
Birth defects in which the vertebrae fail to close are known as spina bifida (split spine).
Anencephaly is an anomaly in which the soft, bony component of the skull and much of
the brain are missing. Encephalocele refers to a herniation or protrusion of various
amounts of brain and meninges through a defect in the skull, resulting in a saclike
structure.

Question 22

Originates in the neural crest that normally forms the sympathetic ganglia and adrenal
medulla.

Answer 22

Neuroblastoma

Question 23

Develops in the fourth ventricle.

Answer 23

Ependymoma

Question 24

Develops in the vermis of the cerebellum and may extend to the fourth ventricle.

Answer 24

Medulloblastoma

Question 25

Originates from the pituitary or hypothalamus.

Answer 25

Craniopharyngioma

Question 26

Causes unilateral symptoms such as nystagmus.

Answer 26

Cerebellar astrocytoma