Board Review Quiz Answers

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					                        Board Review Quiz Answers
                                  June 3
  Allergy/Immunology/Behavior/Development/Neurology/Anticipatory Guidance

Question 1 (2010:4:A)
The diagnosis of lead poisoning or increased lead absorption depends on the measurement of
blood lead concentrations. In the 1990s, both the American Academy of Pediatrics and the
Centers for Disease Control and Prevention recommended universal blood lead screening of 1-
and 2-year-old children, but because of the substantial decrease in the prevalence of elevated
blood lead concentrations, the criteria for screening are changing in many communities. Thus,
it may be helpful to contact your local health department to determine if children in your area
are at risk for environmental lead exposure.

Although blood lead concentration can be measured most accurately from a sample obtained
by venipuncture, a capillary specimen obtained by fingerstick is the most appropriate
screening test for the toddler described in the vignette. The specimen must be obtained
carefully to avoid contamination from lead on the skin. Capillary specimen values greater than
10 mcg/dL (0.5 mcmol/L) must be confirmed by a venous sample because of the possibility of
skin contamination causing a false-positive result.

Although obtaining a complete blood count with smear and measuring serum ferritin and
serum iron may be useful in the diagnosis and management of children who have anemia,
including that associated with environmental lead exposure, these tests are not definitive for
determining exposure to environmental lead. Finally, hair evaluation for lead poisoning is
neither sensitive nor specific due to the lack of correlation with blood lead values and should
not be used.

American Board of Pediatrics Content Specification:
    Know the screening tests available for blood lead concentration

Question 2 (2010:12:C)
Protection against infectious diseases is an important issue in preparing children and adults for
international travel. Clinicians can obtain specific knowledge of available vaccines and
prophylaxis for certain conditions from the American Academy of Pediatrics 2009 Report of the
Committee on Infectious Diseases (Red Book®) and the travelers' health site of the Centers
for Disease Control and Prevention. Travel to India involves a potentially increased exposure
to malaria, hepatitis A, measles, polio, and Salmonella typhi. However, there are other
considerations in recommending various preventive measures for travelers.

Measles may be encountered more commonly in many parts of the world, including India.
Accordingly, measles vaccine is recommended for 6- to 11-month-old children, and the 7-
month-old girl in the vignette should be given a dose of measles vaccine. She still will require
two doses of measles-containing vaccine after 1 year of age because the immune response
may be suboptimal at her young age. If the 9-year-old boy is up to date on immunizations, he
requires no additional measles vaccination.

Although exposure to malaria is a concern on a prolonged trip to India, resistance to
chloroquine is a major concern in this region, as it is in all of South and Southeast Asia, sub-
Saharan Africa, and tropical areas of South America. Available agents for resistant malaria
prophylaxis in infants and children include atovaquone/proguanil and mefloquine. Doxycycline
can be used in children older than 8 years of age.

Hepatitis A is a concern, but hepatitis A vaccine is not approved in children younger than 1
year of age. Intramuscular immunoglobulin is recommended for children younger than 1 year
of age, as the baby in the vignette, traveling to an endemic area. The boy should receive his
first dose of hepatitis A vaccine at least 2 to 4 weeks before departure if he has not been
immunized previously, with completion of the two-dose series 6 to 12 months later.
Although polio exposure may be a concern, if both children are up to date in their vaccination
series, no additional polio vaccine is indicated. Finally, typhoid vaccine might be indicated for a
trip to India that lasts longer than 2 weeks, but neither of the two licensed vaccines is
indicated in children younger than 2 years of age.

American Board of Pediatrics Content Specification:
    Be aware of the special needs of children traveling outside the United States, including
       immunizations and other forms of prophylaxis, their indications, and contraindications

Question 3 (2010:43:C)
The Wechsler Intelligence Scale for Children (WISC-IV) is used to assess a child's mental
ability in comparison with the abilities of other children of the same age via a numerical score
referred to as the full-scale intelligence quotient (IQ). The scores on a cognitive test are used
to predict how a person will function academically.

The WISC-IV consists of 15 subtests: 10 core subtests and 5 additional optional subtests. The
subtests are grouped into four composite scales known as factor scores. The individual factor
scores provide more detailed information regarding the child's mental ability than does the
full-scale IQ score. The verbal comprehension factor assesses skills such as verbal knowledge
and how a person uses verbal skills in novel situations. The perceptual reasoning factor
evaluates the ability to reason and organize material that is seen without the use of words.
The working memory factor is based on the ability to remember information and either to
manipulate it or use it to perform calculations. The processing speed factor assesses the speed
of processing information.

The girl described in the vignette is unable to complete tasks within time limits, indicating that
she has difficulty with the speed of processing simple visual information without making a
mistake. Therefore, the score that is most likely to be affected for her is the processing speed

Factor scores on the WISC-IV should be fairly similar. A substantial difference between scores
suggests a greater likelihood of a learning or cognitive disability.

American Board of Pediatrics Content Specification:
    Recognize that the full subtest profile of scores on the Wechsler Intelligence Scale for
       Children is more useful than the full-scale IQ score alone

Question 4 (2010:75:B)
The child described in the vignette shows clinical features of an autistic disorder, a
heterogeneous neurodevelopmental disorder (see Table 1 at for complete diagnostic
criteria). Affected individuals have impairments in three specific areas: reciprocal social
interactions, verbal and nonverbal communication, and range of activities or interests. The
clinical presentation is specific to the child, with differing degrees of impairment in each of the
three core symptom areas.

The hallmark of autism is abnormal social interactions. Children lack the ability to share
interests with others (joint attention skills) using verbal or nonverbal communication. They
commonly show weakness in eye contact. Their interaction may range from aloofness and an
unawareness of other people to having varied or odd interaction with others. Language
development commonly is delayed, and children may have immediate or delayed echolalia,
unusual intonation, and repetitive speech. Children who have autism may engage in repetitive
play and show little imaginative play. They may focus on sensory aspects of objects or develop
obsessions about unusual objects (stop signs, elevators). They often have difficulty handling
transitions and may engage in repetitive hand or body movements. Many affected children
have cognitive impairment. Children who have subthreshold clinical features (some but not all
of the features) may receive the diagnosis of pervasive development disorder-not otherwise
specified within the autism spectrum.

Red flags of development that warrant further evaluation for possible autism include:
    No babbling by 9 months
    No gesturing by 12 months
    No single words by 16 months
    No functional nonecholalic 2-word phrases by 24 months
    Any loss of language or social skills at any age

Neither a diagnosis of expressive language disorder nor obsessive-compulsive disorder would
account for the impaired social engagement exhibited by the boy in the vignette. Individuals
who have Asperger syndrome (Asperger disorder in DSM-IV TR) have impairments in social
interaction and restricted interests and activities, but they have relatively preserved cognitive
and language functioning, in contrast to the delays in developing language reported for the
child in the vignette. Rett syndrome almost exclusively affects females and presents with a
slowing of motor development between 6 and 18 months of age. Between ages 1 and 4 years,
the child exhibits a decline in social interactions, cognitive abilities, purposeful hand
movements, and speech.

American Board of Pediatrics Content Specification:
    Know the clinical features of autism spectrum disorder

Question 5 (2010:123:A)
Multiple factors contribute to a family's decisions regarding their child who has confirmed
hearing loss. Language-based early intervention results in superior expressive and receptive
communication abilities compared with those of children identified at later stages of
development. Family involvement, including verbal and nonverbal (gestures) communication,
has a more significant positive effect on language development than any specific type of

Hand-cued speech ( consists of eight different handshapes (represent
consonants) and four different hand locations around the speaker's face (represent vowels).
Manually coded English employs a visual representation of the spoken English language. Signs
and finger spelling are used to represent spoken English.

The goal of the oral-aural method of communication is to develop spoken language and gain
inclusion in the mainstream both in school and society. People who employ this auditory-oral
approach use their aided residual hearing as well as reading of speech, facial expressions, and
naturally occurring gestures. Such an approach requires consistent use of hearing aids/FM
technology and provision of auditory training and speech therapy as well as lip-reading.

The bilingual-bicultural (Bi-Bi) philosophy of the National Association of the Deaf
( promotes communication in two languages (visual and a form of spoken) for
children who are deaf so they can be a part of both deaf and hearing communities. The Bi-Bi
approach supports early language learning through American Sign Language (ASL) and a form
of spoken English taught as a second language later in elementary school.

Of note, children who have hearing loss of less than 90 dB usually benefit from conventional
amplification systems. For children who have severe-to-profound sensorineural hearing loss
affecting both ears, cochlear implantation may be considered. This procedure leads to the
ability to perceive sound signals. Although results are highly variable, the procedure is most
successful when undertaken early in life.

American Board of Pediatrics Content Specification:
    Know the major approaches to education of the deaf child
Question 6 (2010:187:D)
A 2½-year-old child who is not yet speaking should have his hearing evaluated, and he should
be referred for a developmental evaluation to determine whether he has an isolated language
disorder or a pervasive social impairment. A brain imaging study is not indicated for a child
who has a normal head circumference and no neurologic symptoms or findings. If the boy in
the vignette had significant language regression or episodes of uninterruptable staring,
neurologic evaluation and electroencephalography should be considered. A developmental
evaluation should be considered if there is a strong family history of developmental delays.
Reassurance and a return for evaluation in 6 months is not appropriate; not saying words at
the age of 2½ years indicates a need for neurodevelopmental evaluation.

American Board of Pediatrics Content Specification:
    Plan the diagnostic evaluation of a 2 1/2 year-old boy who does not say any words

Question 7 (2010:247:B)
Fragile X syndrome is an X-linked disorder of dysmorphic features and intellectual disability
(usually moderate) with autistic features that is estimated to occur in 1 in 4,000 males. Fragile
X syndrome is one of a group of disorders caused by progressive expansion, through
generations, of a trinucleotide repeat sequence (in this case, CGG) that leads to disruption of
gene function. Other conditions caused by trinucleotide repeat expansion include myotonic
dystrophy and Huntington disease. The gene that is disrupted in fragile X syndrome is FMR1.

To predict the result of FMR1 disruption for an individual, it is important to know the average
number of CGG repeats in the general population as well as the phenotypes associated with
various expansion sizes. Typically, humans have 5 to 40 CGG repeats in exon 1 of the FMR1
gene. An "intermediate" allele size of approximately 41 to 58 repeats is not associated with an
unusual phenotype and is of unclear significance; rarely, alleles of this size have been reported
to expand in subsequent generations. Allele sizes of approximately 59 to 200 repeats are
referred to as "premutation" alleles, and individuals who are premutation carriers usually have
normal intelligence but may have some features of fragile X syndrome; they also may be at
increased risk for fragile X-associated tremor/ataxia syndrome (FXTAS) or premature ovarian
failure. Allele sizes of more than 200 repeats are referred to as "full mutations." Once the
allele reaches this size, it is methylated, which effectively silences FMR1 expression, resulting
in fragile X syndrome.

The clinical presentation of fragile X syndrome in males varies according to age. Prepubertal
boys may be large for age (in both height and weight) and have relative macrocephaly. They
often exhibit hypotonia and may have gastroesophageal reflux and recurrent otitis media.
They have motor and speech delays and display behaviors such as hand-flapping and wrist-
biting. They are almost always intellectually disabled, with abilities falling within the moderate
range of intellectual deficit. As they grow, their faces elongate, and the prominence of the
forehead, ears, and jaw becomes more noticeable. After puberty, they have striking

Females who have fragile X syndrome have highly variable presentations. Approximately 50%
of those who have a full fragile X mutation are intellectually disabled, with features and
behaviors similar to those of affected boys, although they typically are less severely affected
than males who have equivalent mutations. The other 50% are intellectually normal. The
leading theory as to the cause of intellectual variability in affected females is that the ratio of
active "normal" Xs to active Xs with the FMR1 mutation in brain cells predicts intellectual
ability; a predominance of active, "normal" Xs is associated with normal intellectual ability.

The term "anticipation" refers to the increasing severity of a disease as it is passed from
generation to generation. Disease anticipation occurs in fragile X syndrome, but it is not
possible to predict an expansion of the CGG sequence each time a conception takes place.
Also, because the FMR1 gene is silenced when there are greater than 200 repeats, the person
who has 300 repeats is not expected to be more severely affected than the person who has
200 repeats. Therefore, women who have full mutations are not expected to have children
who are more severely affected than their full-mutation brothers.

Approximately 20% of female premutation carriers have premature ovarian failure, but female
full mutation carriers typically have normal fertility.

American Board of Pediatrics Content Specification:
    Understand the range of intellectual deficit in the fragile X syndrome in males and

Question 8 (2009:11:B)
Legal blindness is defined as central visual acuity with corrective lenses of 20/200 or less in
the strongest eye or a limited visual field that extends to an angle of 20 degrees. Congenital
blindness occurs in 30 per 100,000 births. More than 50% of children who have visual
impairment also have developmental disabilities, such as cognitive-adaptive disability,
seizures, hearing impairments, and learning disorders. In many of these cases, the disabilities
result from central nervous system pathology. Postnatal blindness, which accounts for
approximately 8% to 11% of all childhood blindness, can be caused by infections, trauma, or
tumors. Retinoblastoma is the most common primary malignant intraocular tumor of
childhood. The initial finding in most cases is a white pupillary reflex (leukokoria) (Item C11).
Advanced tumors may be treated with enucleation.

Children who have congenital or acquired (eg, due to retinoblastoma) blindness without
associated neurologic abnormalities should not be at increased risk for motor or cognitive
impairment. They are not at increased risk for language-based learning disabilities or autism
spectrum disorders. However, children who have significant visual impairment may begin to
walk at an older age (18 to 22 months) than sighted children due to different exposure to
motor exploration. They typically develop language skills at the same time (12 months) as
sighted children. Children who have visual impairments should be provided with much physical
contact that includes hugging and comforting. They should be encouraged to partake in self-
help skills and exploration of their environment.

American Board of Pediatrics Content Specifications:
    Understand the variations in the developmental sequence that are associated with
       congenital visual impairment

       Recognize the effects of visual impairment on motor, language, and emotional
        development in infants and preschool children

Question 9 (2009:75:C)
The frequency of learning difficulties is increased in individuals who have a positive family
history for learning disorders or genetic syndromes such as neurofibromatosis type 1 (NF-1),
fragile X syndrome, or velocardiofacial syndrome (VCFS). It is important to obtain a family
history when evaluating children who have suspected learning disorders to ascertain if there is
a possible genetic cause. A thorough family history also may identify speech or language
problems in up to 30% of first-degree relatives of children who have language delays, a risk
factor for learning difficulties.

The multiple café au lait macules and axillary freckling described for the boy in the vignette
meet diagnostic criteria for NF-1. The offspring of an affected individual has a 50% risk of
inheriting the altered NF1 gene, which can be detected by molecular genetic testing, although
this rarely is necessary for diagnosis. Learning disabilities occur with increased frequency in
those who have a family history of NF-1, ranging from 40% to 60%.

Fragile X syndrome, the most common genetic cause of intellectual disabilities, occurs in 1 in
1,200 males and 1 in 2,500 females. A mutation in the FMR1 gene (Xq27.3) leads to
expansion of the CGG trinucleotide repeat. Women who have alleles in the range of 29 to 200
CGG repeats are at risk for giving birth to affected children. Males who have fragile X
syndrome have large heads, long faces, large ears, and macro-orchidism but no skin findings.
Males who have the full mutation have mean intelligence quotient (IQ) scores of 40; affected
females have mean IQ scores in the low-average to borderline range.

Velocardiofacial syndrome affects 1 in 4,000 individuals, and 10% of cases are inherited in an
autosomal dominant pattern. The condition is caused by a microdeletion on chromosome
22q11.2 and may be associated with cardiac and facial anomalies, but not cutaneous
abnormalities. Learning difficulties are reported in 82% to 100% of affected children.

Hypomelanosis of Ito is a congenital skin disorder that is characterized by linear or whorled
hypopigmentation that follows the lines of Blaschko, the paths of embryonic neural crest cell
migration (Item C75A). There is no evidence for genetic transmission. Associated intellectual
disability has been reported in as many as 70% of cases, seizures in 40%, and microcephaly
in 25%. However, these high percentages may be the result of selection bias, and the actual
frequency of associated abnormalities may be lower.

Tuberous sclerosis complex (TSC) is inherited in an autosomal dominant pattern, but as many
as two-thirds of cases represent new mutations. TSC may present during infancy with infantile
spasms and a hypsarrhythmic electroencephalographic pattern. Autism is seen 1% of affected
individuals. The most common skin finding is hypopigmented macules that have been likened
to an ash leaf; they are seen in more than 90% of affected individuals (Item C75B).

American Board of Pediatrics Content Specification:
    Know the importance of family history in the evaluation of a child with learning

Question 10 (2009:38:D)
Low tone and seizures are relatively common neurologic problems. Low tone is a nonspecific
finding that may be due to disease in the central or peripheral nervous system, but the
occurrence of a seizure suggests a central cerebral cause. Neuroimaging with brain magnetic
resonance imaging (MRI) generally is recommended for any infant who has a seizure because
congenital brain malformations are more common at this age. The combination of such
cerebral symptoms and pigmentary abnormalities of the skin are an indication to obtain brain
MRI to assess for a possible neurocutaneous disorder. The seizures, hypotonia,
hypopigmented macules, and MRI findings described for the child in the vignette are most
suggestive of tuberous sclerosis complex (TSC) (Item C38A).

Incontinentia pigmenti is characterized by spasticity rather than hypotonicity, and skin findings
include swirled hyperpigmentation following the line Blaschko (Item C38B). Skin findings
associated with neurofibromatosis type 1 include café au lait macules (Item C38C), axillary
freckling, and iris Lisch nodules (Item C38D). Although Sturge-Weber syndrome can be
associated with seizures in the first postnatal year, the primary skin finding is a port wine stain
(Item C38E). Neither seizures nor skin abnormalities are seen with von Hippel-Lindau

Initial management of this patient centers on the chief complaint, which is the seizure. In
most cases, no treatment is recommended in a child after a first unprovoked seizure.
However, the recurrence risk is much greater in TSC.

Subsequently, diagnostic assessment should be directed toward confirming whether this child
has TSC. In many cases, this is a clinical diagnosis based on the characteristic findings of skin
examination and the cerebral complications. However, many other organs may be involved at
presentation or during the child's lifetime, including the eyes, kidneys, lungs, and heart. In the
future, this child is at risk for developmental learning difficulties, behavior problems that can
include features of autistic spectrum disorders, and malignancies. Given the autosomal
dominant inheritance, proper management involves assessment of the parents and genetic
counseling. Commercial genetic testing is available and is helpful in cases where clinical
features, particularly early in the disease, do not confirm the diagnosis. Genetic testing may
have false-negative results due to mosaicism, ie, some organs may be affected due to TSC1 or
TSC2 mutations that are not present in blood. Given the complexity of this diagnosis, many
experts recommend that children who have TSC be cared for in multidisciplinary specialty

American Board of Pediatrics Content Specification:
    Recognize the clinical manifestations of tuberous sclerosis, and manage appropriately

Question 11 (2009:70:E)
The child described in the vignette has findings consistent with an acute spinal cord lesion,
which is a neurologic emergency. In some cases, emergency neurosurgery is needed for
lesions causing acute spinal cord compression, and the initial diagnostic emphasis should be
directed toward identifying such lesions. The first step is to localize the problem to the proper
level of the nervous system: brain, brainstem/cerebellum, spinal cord, nerve, junction, or
muscle. Such localization not only allows for urgent appropriate diagnosis and treatment but
can reduce discomfort, risks, and costs of inappropriate diagnostic testing. Urgent phone or in-
person consultation with a neurologist or neurosurgeon can be useful before ordering testing.

The back pain, acute bilateral flaccid weakness, and sensory loss below the level of the lesion
described for the girl in the vignette localize this problem to the spinal cord. In this case, the
rapid onset of symptoms and the preservation of vibratory and proprioceptive sensation point
to the anterior cord, bilaterally, which is consistent with an anterior spinal artery stroke. Spinal
cord strokes in children are uncommon but can occur after aortic surgery or as a consequence
of thrombotic disorders, infection, inflammatory diseases, or trauma.

Based on the history and examination findings, magnetic resonance imaging (MRI) of the
spine is the test of choice. This should aid in determining the specific location of the lesion and
whether emergency neurosurgery to decompress the spinal cord is needed.

Brain MRI is not the initial modality of choice because of the urgency of the presentation and
the localization of the lesion suggested by clinical findings. If a spinal cord lesion is
radiologically consistent with the diagnosis of transverse myelitis, a subsequent brain MRI with
gadolinium should be obtained to look for evidence of demyelinating lesions in the brain, which
is supportive of a diagnosis of multiple sclerosis.

A subsequent lumbar puncture also may help identify the cause of the patient's symptoms, but
it may not be necessary and should not delay obtaining the spine MRI. Lumbar puncture is the
appropriate test for suspected Guillain-Barré syndrome, an acute inflammatory demyelinating
polyneuropathy, which can present with weakness beginning in the proximal legs but not with
the sensory findings seen in this child. Lumbar puncture is also helpful for identifying
inflammatory causes of spinal cord disease. Somatosensory evoked potentials are
neurophysiologic tests that document the integrity of sensory pathways from peripheral nerves
through the spinal cord to the brain. They are not part of standard emergency management in
this clinical setting. Nerve conduction studies and electromyography are not needed to assess
the nerves because the problem localizes to spinal cord.

American Board of Pediatrics Content Specification:
    Plan the initial neurodiagnostic evaluation in a patient with acute spinal cord

Question 12 (2009:118:E)
For a child who has a first unprovoked seizure, as described in the vignette, safety concerns
(no unsupervised time in bathtub or pools, wearing a helmet while on a bike or scooter) and
seizure first aid should be reviewed with the parents and documented in the chart. Treatment
after a single seizure in childhood is not recommended, no matter what EEG shows.
In some cases, retrospective evaluation of children suggests that they have had subtle
complex partial seizures or previously have been found after an unwitnessed seizure.
Therefore, it is critical for the physician seeing the child after an apparent first seizure to
obtain a very careful history to be certain that the seizure is, indeed, the first.

The most important diagnostic decision after a first unprovoked seizure is whether to obtain
neuroimaging to diagnose a focal, treatable cause for seizures. Neuroimaging should be
obtained after a first unprovoked seizure when the seizure occurs in the first year after birth,
is focal/asymmetric, or begins with a stare and subsequently generalizes. Neuroimaging also
should be obtained after a first unprovoked seizure when the history or physical examination
results indicate probable focal central nervous system pathology, such as if the child has
unilateral weakness or when postictal confusion is prolonged, particularly if the child is febrile
(to rule out herpes encephalitis).

Obtaining an EEG is recommended by published practice guidelines. There are two primary
problems to keep in mind when deciding whether to order an EEG:

1) Inter-reader agreement in the interpretation of EEGs is low. The level of training of
neurologists reading pediatric EEGs may be low in some communities, which is a particular
problem for neonatal EEGs, and even experienced EEG readers frequently differ in their visual

2) Positive and negative predictive values are not very informative. The sensitivity of EEG
varies widely, depending on who reads it, but at best is approximately 50%; that is, about
50% of children who have epilepsy and 50% of children who have a first unprovoked seizure
that eventually will recur have epileptiform EEGs, but the rest have normal EEGs. Accordingly,
a normal EEG reading does not rule out recurrence or epilepsy and only means that a
recurrent seizure is somewhat less likely. The specificity after first seizure is, at best, about
70%; that is, about 30% of children who do not have a seizure recurrence still have
epileptiform discharges on the EEG. Thus, a positive EEG also does not predict epilepsy

Repeat EEGs with sleep deprivation have been advocated by neurology practice parameters for
many years in cases where the first EEG is read as normal and sleep was not present. The
best available evidence suggests, at most, modest benefit to this practice if used routinely in
children. Any benefits of the higher yield should be weighed against the potential for additional
false-positive results, the time for the additional trip to the EEG laboratory, missed school and
work, cost, and the burden of sleep deprivation. After a first seizure, the repeat EEG will not
result in any additional information that changes acute management.

Regardless of EEG results, two or more unprovoked seizures in a child are diagnostic of
epilepsy and warrant treatment and consultation with a neurologist for selection of medication.
Because phenobarbital causes sedation and cognitive and behavioral changes in young
children, it would not be used, except in countries where resources for medical care are very
limited. Phenytoin has somewhat erratic absorption and can cause gingival hyperplasia in
children, so it is not first-line therapy for a new diagnosis of epilepsy. Carbamazepine is a
good choice for a child diagnosed with partial epilepsy, but not for generalized epilepsy.
Valproic acid is a good choice for both partial and generalized epilepsy in children older than
age 2 years. Each of these generic choices, along with the plethora of new medications, has
unique adverse event profiles, which physicians must understand.

American Board of Pediatrics Content Specification:
    Know the value and limitations of neurodiagnostic techniques such as evoked
       potentials, electromyography, and electroencephalography
Question 13 (2010:15): E

The boy described in the vignette is exhibiting a common form of food allergy called food
pollen syndrome or oral allergy syndrome (OAS). OAS is seen in 30% to 40% of children who
have allergic rhinitis. Certain foods contain proteins that are similar to airborne allergens, and
patients who are allergic to an aeroallergen are at risk of developing reactions to the cross-
reacting food protein (Item C15).

In most cases, symptoms are isolated to the oropharynx, where food comes in contact with a
mucosal surface, and include lip, tongue, and oral mucosal pruritus; tingling; and occasionally
angioedema. Interestingly, because these food proteins are heat-labile, cooking the food (eg,
apple pie) negates its antigenic properties. Although symptoms typically are mild, there are
reports of severe reactions. In one recent review involving 1,361 patients who had OAS, 8.7%
experienced systemic symptoms outside the gastrointestinal tract, 3% experienced symptoms
other than oral symptoms, and 1.7% experienced anaphylactic shock.

Because OAS is relatively specific to particular cross-reacting food(s), patients do not need to
avoid other fruits or vegetables to which they have not experienced reactions. Avoidance of
unrelated foods (eg, milk, eggs) is not recommended unless the history suggests a previous
reaction. The decision to avoid causative foods can be based on the severity of reaction.
Referral to an allergist typically is reserved for situations when skin testing is desired or if the
child has experienced systemic symptoms. Skin testing is performed using a commercial
extract or the fresh fruit or vegetable. When using fresh food, the sensitivity of skin testing
with a history of reproducible reactions is close to 90%, while the negative predictive value is
more than 90%. The skin prick device is pressed into the food and then pressed in the skin
(so-called "prick-prick" skin test).

Other immunoglobulin (Ig) E food reactions include atopic dermatitis, eosinophilic esophagitis,
and specific food allergy. In the United States, 85% of specific food allergies are due to egg,
milk, wheat, soy, peanuts, tree nuts, fish, and shellfish. Most children who have IgE food
allergies react to only one or two causative foods, although children who have tree nut allergy,
atopic dermatitis, and eosinophilic esophagitis often have IgE-mediated reactions to multiple

American Board of Pediatrics Content Specification:

       Know that more than 90% of food-allergic individuals demonstrate clinical responses
        to only 1 or 2 foods

Question 14 (2010:31): A

Clinicians should be aware that many unconventional and unproven testing methods are still
promoted for the diagnosis and management of allergic conditions. For example, applied
kinesiology theorizes that an allergen or irritant substance provokes weakness when the
person ingests, holds, or even stands in close proximity to the offending agent. To date, no
conclusive evidence supports this theory or test.
The cytotoxic test is an in vitro test involving microscopic evaluation of blood after placing a
drop of the offending agent (eg, food, mold) on a slide containing the patient's blood. Changes
in the appearance, size, shape, and integrity of leukocytes are interpreted as a "positive"
response. A thorough United States Food and Drug Administration review has concluded that
the efficacy of the cytotoxic test is unproven.

The pulse test evaluates whether an increase or decrease in pulse rate follows food ingestion,
injection, or sublingual application and is interpreted as an "allergy" if a change occurs.

Finally, provocation-neutralization is a nonstandardized test for food and inhalant allergies. A
series of dilutions of an allergen are injected in the upper arm until the patient reports
subjective sensations. A progressive series of lower concentrations subsequently are
administered until the sensation abates. The lower dose is used for injection treatment to build
immunologic tolerance for the offending trigger. Both the testing and treatment method are
unproven and should be considered similar to placebo therapy.

Finally, Candida immunotherapy or avoidance of yeast ingestion for patients diagnosed with
yeast or Candidahypersensitivity is unproven.

The parent in the vignette is concerned for mold allergy. Molds generally are believed to have
three effects: direct infection through ingestion or inhalation, release of toxins or irritants as
mold byproducts, and an immune response (eg, allergic bronchopulmonary aspergillosis,
allergic fungal sinusitis, allergic rhinitis, asthma). Significant water damage, leaking water
sources, or visible mold growth represent real health concerns. Commercial testing for mold
can provide some information, but quantifiable amounts are found in 80% of homes in the
United States. Thus, the presence of mold does not necessarily indicate causation. For
example, Alternaria alternata is linked to fatal asthma but is primarily an outdoor
aeroallergen. Allergy skin prick testing or blood testing can aid in detecting immunoglobulin E-
mediated responses to molds and other allergens and is reasonable as part of determining the
cause of this adolescent's asthma exacerbations.

American Board of Pediatrics Content Specification:

       Recognize fad therapies that have no scientific basis (eg, Candida immunotherapy) for
        management of allergic conditions

Question 15 (2010:63): D

The boy described in the vignette experienced an anaphylactic reaction, a potentially life-
threatening event. In children, the most commonly identified causes for anaphylaxis are food,
insects, drugs, latex, and vaccines. Food allergy is the most common cause of anaphylaxis in
the home or school setting and accounts for an estimated 50% of all pediatric cases annually.
Some 85% to 90% of allergic reactions to food in children are due to milk, egg, soy, wheat,
peanuts, tree nuts, fish, and shellfish. Peanuts and tree nuts account for most cases of fatal
anaphylaxis from foods in the United States.

Recently, a panel of experts published a set of clinical criteria for diagnosing anaphylaxis (Item

The skin and respiratory system are the most commonly affected systems in cases of food
allergy-induced anaphylaxis, as described for the boy in the vignette. Fatal anaphylaxis almost
always is due to airway edema and subsequent respiratory failure.

For a person experiencing anaphylaxis, epinephrine should be administered immediately and
without delay. Observation of the child while calling his parents wastes precious time in this
situation. In the school setting, self-injectable intramuscular epinephrine is used. Other
methods of delivery, used primarily in the hospital setting, include intravenous, intraosseous,
and via an endotracheal tube. Current epinephrine injectors are available in two strengths:
0.15 mg and 0.30 mg. The child in the vignette, who weighs more than 30 kg, should be given
the 0.30-mg dose, preferably in the lateral thigh. Antihistamines may decrease pruritus or
flushing, but their effect has a slow onset, and they are not recommended as the initial
treatment for anaphylaxis. Because some children may require additional doses of epinephrine
and observation, emergency services should be called, but waiting for them to arrive to make
a decision regarding the initial dose of epinephrine is not recommended.

Caregivers of children who have experienced food-induced anaphylaxis should have
epinephrine readily available, understand the indications for its use, have a written action
plan, and understand the proper technique for use of self-injectable epinephrine devices.

American Board of Pediatrics Content Specification:

       Plan effective treatment of anaphylaxis

Question 16 (2010:127): D

During the past 4 decades, there has been a substantial increase in the incidence of atopy (ie,
atopic dermatitis, food allergy, asthma, and allergic rhinitis). A history of atopy in a first-
degree relative or parent is clearly the greatest risk factor for atopy. However, nongenetic
factors such as infections, child care exposure, antibiotics, food choices, and maternal dietary
choices have been studied intensely to determine why some "at-risk" infants, such as those
who have parents who have atopy, eventually develop atopic disorders while others do not.

Although the atopy status of the parents of the boy in the vignette is unknown, the multiple
wheezing episodes associated with viral upper respiratory tract infections that the boy
experiences suggest lower airway inflammation, a hallmark of asthma. One landmark study,
the Tucson Children's Respiratory Group Study, enrolled children at birth and now has followed
them for more than 15 years, assessing the risk factors associated with development of atopic
disorders. Regarding asthma, investigators identified three primary groups of patients: early
transient wheezers, persistent wheezers, and late wheezers. Almost 80% of the early
wheezers (ie, wheezing associated with a viral illness prior to age 3 years) did not develop
persistent asthma. Late wheezers (ie, wheezing episodes occurring after age 6 years) had
increased risk for persistent asthma. However, if the infant was male and had wheezing during
a respiratory syncytial virus (RSV) infection, he would have a 15-fold increased risk of
developing later asthma. Other risk factors identified for later asthma included positive skin
tests to aeroallergens prior to age 6 years, development of atopic dermatitis (the initial step
on the so-called "allergic march"), and increased total serum immunoglobulin E
The role of maternal diet and atopy risk is still controversial. In the past, mothers were
advised to avoid highly allergenic foods such as peanuts and tree nuts during pregnancy.
Current evidence suggests that maternal dietary restriction of highly allergenic foods does not
play a role in prevention of atopic diseases. Further, in utero exposure to these foods actually
may provide immunologic tolerance. In 2008, the American Academy of Pediatrics
recommended that mothers be allowed to eat a regular healthy diet without specific food

Other general observations from meta-analysis and controlled studies regarding the
development of atopic disorders include:

       Breastfeeding for 3 months, compared with ingestion of cow milk formula, afforded a
        decreased risk for atopic dermatitis in "at-risk" infants
       Exclusive breastfeeding may decrease wheezing episodes for children younger than 4
        years of age but may not affect asthma risk in children older than 6 years of age
       Delaying the introduction of solid foods past 4 to 6 months, perhaps even highly
        allergic ones such as fish, peanut butter, and eggs, does not appear to have a
        protective effect on development of atopic disease

American Board of Pediatrics Content Specification:

       Know the factors that influence the incidence of atopy in infants

Question 17 (2010:143): E

Exercised-induced asthma (EIA) results in a transient narrowing of the airway following
vigorous exercise and is associated with a 10% to 15% decrease in the forced expiratory
volume in 1 second (FEV1). A number of mechanisms are postulated for EIA, but the most
accepted one is based on the decreased warming and humidification of inhaled air during
exercise. Upon completion of exercise, there is a marked influx of fluid due to rapid
rewarming, which results in mucus production and airway narrowing. Because temperature
change is a key aspect of EIA, exercise or sports in cold weather provokes EIA more readily
than in warmer weather. Also, a slow warm-up, particularly in cold weather, results in a more
gradual change in airway temperature and can lessen EIA symptoms.

EIA symptoms such as cough, shortness of breath, and wheezing may begin during exercise
but classically peak 5 to 10 minutes after completion of exercise. The more strenuous the
exercise, the more intense the asthma attack. For example, running produces more severe
airflow limitation than jogging, which, in turn, produces more limitation that walking. Short,
intense bouts of work lasting fewer than 2 minutes produce fewer problems than longer
periods of effort because of the shortened time of airway cooling. EIA symptoms usually
resolve spontaneously after 30 minutes of rest.

Exercise is a very common asthma trigger for children, with 70% to 90% of children who have
asthma demonstrating EIA symptoms. Pretreatment with a short-acting beta2 agonist is
appropriate for isolated EIA. Because most patients who have EIA will be identified with
persistent asthma, the latest Global Initiative for Asthma guidelines, published in late 2008,
continue to recommend treatment with inhaled corticosteroids to control any underlying
persistent asthma. Finally, acute episodes can be attenuated by having the athlete warm up
before strenuous exercise.

Clinically, exercise challenges usually are performed if the diagnosis of EIA is in doubt or if the
patient is not responding appropriately to usual EIA therapies such as beta2 agonists, inhaled
corticosteroids, or leukotriene antagonists. Prior to exercise, two baseline spirometry
measurements are performed. Ideally, the FEV1measurements should not differ by more than
3%. The patient then exercises, preferably for the same duration and in the same conditions
(eg, running outside on a cold day) that have provoked symptoms previously. Postexercise
spirometry is performed at 5, 10, 15, and 30 minutes after exercise. During this challenge, a
decrease of 15% in FEV1 is considered consistent with EIA. Other protocols available in a
monitored setting include eucapnic voluntary hyperpnea, hypertonic saline challenge, and
inhaled powder mannitol challenge. These require a 10% drop in FEV1 to be consistent with

Other conditions that may result in poor exercise performance include vocal cord dysfunction,
poor physical conditioning (ie, overweight, out of shape), gastrointestinal reflux, poor cardiac
function, and restrictive lung disease.

American Board of Pediatrics Content Specification:

       Recognize the characteristics of exercise-induced asthma (coughing and wheezing
        after 5 to 6 minutes of exercise, gradual improvement after 30 to 30 minutes of rest)

Question 18 (2010:159): D

The girl described in the vignette is suffering an exacerbation of her asthma. Signs and
symptoms of asthma exacerbations include cough, wheezing, shortness of breath, hypoxia,
tachypnea, and atelectasis. Treatment depends on the age of the patient, current medication
use, and severity of the episode. Mild exacerbations may be treated at home with the
assistance of a physician-directed action plan. Initial therapy involves the use of a rapid-acting
beta2 agonist.

For mild exacerbations treated at home, high doses of inhaled corticosteroids may avert the
progression of symptoms. For moderate-to-severe exacerbations, as experienced by this
patient, oral or intravenous corticosteroids are required. A 3- to 5-day course of oral steroids
is adequate for most children, providing a similar outcome compared with intravenous

The need for hospital admission typically is based on the response to therapy in the clinic or
emergency department. Hospital admission would be considered if a patient presents with
cyanosis, apnea, history of previous intensive care unit admission or respiratory failure, peak
expiratory flow less than 60% of predicted after beta2 agonist therapy, increased Pco2 on
blood gas analysis, or requirement for persistent nebulization therapy or supplemental

A common practice for many clinicians is to increase the dose of inhaled corticosteroids during
an asthma exacerbation but not start oral steroids. One study supported quadrupling the dose
during an asthma exacerbation, but other studies, as well as current asthma guidelines,
recommend oral steroids as the mainstay therapy for an exacerbation that does not respond
to beta2 agonists.

National Asthma Education and Prevention Program guidelines address the issue of antibiotics
for asthma exacerbations. Clear manifestations of a bacterial infection should be present
before beginning antibiotic therapy during an asthma exacerbation. Because viral infections
are the most common trigger in younger children, as described in the vignette, antibiotics are
not indicated.

Chest radiography for the girl in the vignette documents right middle lobe atelectasis,
characterized by a wedge-shaped density that extends anteriorly and inferiorly from the hilum
of the lung. This finding often is diagnosed inappropriately as pneumonia and treated with
antibiotics. Atelectasis due to mucus plugging is not an uncommon finding in children who
have asthma exacerbations. Right middle lobe atelectasis and other scattered areas of
atelectasis usually respond to standard asthma therapy (eg, oral corticosteroids, inhaled
asthma medications) and do not require bronchoscopy or chest physiotherapy.

American Board of Pediatrics Content Specification:

       Know that atelectasis associated with an acute exacerbation of asthma does not
        usually require bronchoscopy, antibiotics, or chest physiotherapy

Question 19 (2010:175): B

Exercise-induced asthma (EIA) is not only a problem for children and adolescents who have
underlying persistent asthma but also can affect 10% to 50% of elite athletes. In addition to
ensuring control for underlying persistent asthma, a warm-up period prior to maximal exertion
as well as administration of an inhaled beta2 agonist are recommended to prevent EIA. Short-
acting beta2 agonists, such as albuterol or levalbuterol, are the most common bronchodilators
used. Typically administered 20 minutes prior to activity, short-acting beta2 agonists provide 2
to 4 hours of bronchodilation. However, such treatment may not be effective when anticipated
activity is longer, such as the 8 to 12 hours described for the boy in the vignette. Long-acting
beta2 agonists that are approved for prevention of EIA in children older than 4 and 5 years of
age include salmeterol and formoterol, respectively. However, these agents should not be
used as monotherapy for persistent asthma. Formoterol has a faster onset of action than
salmeterol (10 minutes versus 30 minutes to reach an increase of 15% in forced expiratory
volume in 1 second, and is appropriate for the boy in the vignette.

In December 2008, the Pulmonary-Allergy Drugs Advisory Committee recommended that the
United States Food and Drug Administration (FDA) consider a ban on the use of both
salmeterol and formoterol in children and adolescents. However, the Committee focused on
the use of long-acting beta2 agonists for persistent asthma, citing a meta-analysis in adults
showing increased risk for asthma-related hospitalization, asthma-related intubation, and
asthma-related deaths. At the time of this writing (March 2009), the FDA has not rendered a
decision on this issue.

Leukotriene receptor antagonists (LTRAs) such as montelukast can be used for EIA. Studies
have demonstrated that LTRAs reduce the immediate and late phase of exercise
bronchoconstriction. Interestingly, the response to LTRAs varies from poor to excellent.
Pharmacogenetic studies are ongoing to determine which patient group exhibits the best
response. Anticholinergic inhalers such as ipratropium are not recommended for the treatment
of EIA.

American Board of Pediatrics Content Specification:

       Know the kinetics of short- and long-acting inhaled beta-adrenergic agonists
Question 20 (2010:191): D

The boy described in the vignette experienced a near-fatal reaction to a flying insect, with
signs and symptoms consistent with anaphylaxis. In the United States, stinging insects
causing immunoglobulin (Ig) E-mediated reactions include honeybees, yellow jackets, yellow
hornets, white-faced hornets, paper wasps, and fire ants. The identification of an IgE-
mediated allergic disorder involves identifying the allergen, estabishing a causal relationship
between the allergen and the reaction, and demonstrating the presence of specific IgE via
immediate type skin testing or in vitro testing.

Indications for immediate type skin testing include:

1. Identification of aeroallergen triggers in patients who have asthma
2. Allergic rhinitis that is not controlled with usual medications or if specific avoidance (eg, pet
dander) is desired
3. Food allergy
4. Insect sting allergy
5. Vaccine, drug, or latex allergy
6. Evaluation for moderate-to-severe atopic dermatitis
7. Other conditions, including allergic fungal sinusitis, allergic bronchopulmonary aspergillosis,
and eosinophilic esophagitis

The decision to perform skin or in vitro testing depends on the age of the patient, the desire to
start allergen immunotherapy, time since the reaction, and severity of the reaction.

Allergy skin testing can be performed at any age, but infants and toddlers generally do not
tolerate intradermal skin testing well and may not be able to communicate to their
parent/clinician if they are developing a reaction during testing. In addition, clinicians may
elect to start with in vitro testing in patients who have experienced life-threating reactions, as
described in the vignette. Unfortunately, both skin testing and in vitro testing, when used
alone for assessment of insect sting allergy, may provide false-negative results in up to 25%
of patients. In cases of anaphylaxis, if the results of the initial test (skin or in vitro) are
negative, the second testing modality should be undertaken. If testing is performed too soon
(ie, within 2 weeks of the reaction), results may be negative due to depletion of mast cell
mediators. Generally, skin testing should be performed 4 to 6 weeks after a sting reaction.

Current guidelines recommend that patients who experience less severe reactions (eg, local or
normal reactions, large local reactions, or cutaneous-only symptoms in children younger than
than 16 years of age) do not require testing because of their low risk for future anaphylaxis.
Epidemiologic studies have demonstrated that 25% to 50% of individuals can develop specific
IgE to stinging insects, even after a normal or local reaction. However, such individuals (local
reaction only) should not be tested, based on their normal reactions, and no specific avoidance
measures or immunotherapy are recommended.

Finally, when flying insect testing is performed, a complete set of the five Hymenoptera
venoms (honey bee, yellow jacket, white-faced hornet, yellow hornet, wasp) should be used
unless the specific insect is captured and identified by an entomologist.

American Board of Pediatrics Content Specification:

       Know the indications for immediate-type skin testing

Question 21 (2010:207): A

Based on the 2007 National Asthma Education and Prevention Program Expert Panel Report 3
Guidelines for the Diagnosis and Management of Asthma, the 12-year-old girl described in the
vignette has severe persistent asthma. A stepwise approach is used to identify the severity of
asthma in a new patient and determine the level of control. This stepwise approach accounts
for patient's treatment responses and changes that often occur over time. The choice and
schedule of medications is determined by the level of asthma severity and asthma control.
Severe persistent asthma in children 12 years of age or older requires the initiation of step 4
or step 5 therapy (Item C207).

The preferred treatment includes a medium- to high-dose inhaled corticosteroid plus a long-
acting beta agonist (LABA). Omalizumab is an additional therapy that could be considered for
this girl if she had allergic asthma, with evidence of specific sensitization to associated
allergens and an appropriate total serum immunoglobulin E concentration.

A medium-dose inhaled corticosteroid plus an oral leukotriene antagonist is an alternative to
the previously noted regimen but is not the first choice. An oral leukotriene antagonist or oral
theophylline as monotherapy are only appropriate for step 2 therapy.

In asthma, exposure to allergens leads to an early airway response that develops fully within
10 to 20 minutes. In addition, a late airway response can occur and develop fully 3 to 8 hours
after exposure. Oral and inhaled glucocorticoids inhibit the late-phase reaction but not the
early-phase reaction. Inhaled short-acting and long-acting beta-adrenergic agents are potent
inhibitors of the early-phase reaction. Leukotriene receptor antagonists (montelukast,
zafirlukast) and leukotriene synthesis inhibitors (zileuton) also block the early-phase response
and may have a mild impact on the late-phase response.

American Board of Pediatrics Content Specification:

       Know that corticosteroids interfere with the late-phase but not the immediate
        response to allergen exposure
Question 22 (2009:6): A

The subacute onset of mental status changes described for the adolescent in the vignette
warrants an emergency evaluation. In most cases, neuroimaging is indicated, along with
appropriate laboratory testing.

The relatively nonspecific pain and what her mother perceives as common emotional problems
(apathy in a teenager) probably represent early frontal lobe symptoms. The headache on
awakening and vomiting are concerning for increased intracranial pressure (ICP). Confusion
and psychomotor retardation on the mental status examination indicate involvement of the
central nervous system. A focal, ischemic, ictal, infectious/inflammatory, or toxic/metabolic
process must be identified urgently. A brain abscess is suggested by the prominent facial pain
in this setting; the sinuses are a common source of brain abscesses (Item C6). Brain
abscesses often present only with nonspecific pain and not with fever.

Head computed tomography (CT) scan is preferred for this patient because the constellation of
pain, confusion, and morning vomiting makes a focal intracranial mass a possibility. Increased
ICP is associated with morning vomiting because ICP is highest in the morning. Contrast is
recommended because of the insidious onset, which could indicate either a neoplasm or
infectious process. Intravenous contrast is not needed for all neuroimaging procedures.
However, it increases the diagnostic yield of imaging studies where either neoplasm or
infection is suspected because both typically involve some degradation of the blood-brain
barrier or hypervascularity, resulting in contrast enhancement at the site of the lesion.
Magnetic resonance imaging (MRI) with contrast also is a good choice. The advantage of MRI
is higher spatial and soft-tissue resolution. Disadvantages of MRI compared with CT include:
1) less availability for emergency department studies; 2) need for pharmacologic sedation in
agitated patients because sedation affects mental status, thereby masking disease-related
mental status; 3) longer time in the scanner, which could delay treatment decisions; and 4)
cost. Thus, in most cases, a head CT scan with contrast is preferred as the initial study in the
emergency department.

Electroencephalography (EEG) is an important test for assessment of a patient who has
encephalopathy of unclear cause to rule out nonconvulsive status epilepticus (NCSE),
particularly if the patient is known to have epilepsy. If an EEG cannot be obtained rapidly,
intravenous administration of 0.1 mg/kg lorazepam can treat NCSE immediately, although this
would not clear confusion about other causes. For this adolescent, the facial pain makes the
diagnosis of NCSE less likely than a brain abscess.

A lumbar puncture may be needed to rule out meningitis or encephalitis, but the pain and
morning vomiting more strongly suggest the possibility of an intracranial mass. Lumbar
puncture prior to head CT is not advised in this case because it could reduce pressure below
the foramen magnum and result in herniation from the supratentorial mass. Toxicology
screening and nasal swabs are reasonable but not the preferred initial diagnostic tests because
they will not affect emergency management of the increased intracranial pressure.

American Board of Pediatrics Content Specifications:

       Know the clinical manifestations of brain abscess
       Know the imaging techniques for diagnosing brain abscess
Question 23 (2009:233): E

Evaluation of the patient who has an altered level of consciousness consists of a thorough
medical history, a detailed physical examination, and appropriate diagnostic studies. A sudden
onset over minutes in a previously healthy individual suggests trauma or a cerebrovascular
accident; effects of toxic ingestions may present over several hours; and a more gradual onset
suggests infection, metabolic disease, or a space-occupying lesion. Vital signs, level of
consciousness, pupil size and reaction, motor responses, and skin findings can be crucial in
narrowing potential causes and determining appropriate diagnostic studies. Diagnostic studies
might include blood and urine testing (for potential metabolic, infectious, and toxic causes),
lumbar puncture, computed tomography scan and magnetic resonance imaging (with or
without angiography), brainstem evoked potentials, electroencephalography, and

The teenager described in the vignette has had an acute mental status change, and his
somnolence, hypotension, shallow and slow respirations, and pinpoint pupils are consistent
with an opiate ingestion. Therefore, toxicology screens for confirmation as well as to evaluate
for coingestions are indicated. Evoked potentials may be useful in testing the integrity of the
brainstem and in providing prognostic information for comatose patients, but results are
nonspecific and rarely helpful for initial diagnosis. Chest radiography generally is of little value
in the assessment of a comatose patient. Although seizures may produce an altered level of
consciousness, no suggestion of seizure activity is present in this patient that would
necessitate electroencephalography. The patient's age makes an inborn error of metabolism
unlikely, and serum amino acid measurement can be deferred.

American Board of Pediatrics Content Specification:

       Plan the initial phase of evaluation for an altered level of consciousness

Question 24 (2009:54): A

The most common cause of hemorrhagic stroke in children is vascular malformation, of which
there are two types: arteriovenous malformations (AVMs) and cavernous malformations.
These can present in childhood with hemorrhage that leads to headache and seizures, as
described for the boy in the vignette. Severe, "worst-ever" headache; seizure; and mental
status change are indications for emergency evaluation and imaging of the central nervous
system. The computed tomography scan obtained for this boy shows a contrast-enhancing
tortuous vascular mass without surrounding edema or midline shift (Item C54A).

Seizures are not believed to cause brain damage in children, except in rare cases. A large
hemorrhage can cause seizures, but seizures cannot cause a large hemorrhage.
Ependymomas are one of the more common brain tumors in children. They emerge from the
ependymal lining of ventricles, do not hemorrhage, and typically occur in the posterior fossa of
young children (Item C54B). Therefore, they present more indolently, with headache and
cranial nerve findings. Glioblastoma multiforme, the highest grade astrocytoma, is uncommon
in young children. Although glioblastoma multiforme can hemorrhage, it does not have a
tortuous vascular appearance on imaging and has surrounding edema. Herpes encephalitis
causes hemorrhagic necrosis (Item C54C) and can present with seizures, but usually the
patient is febrile and the characteristic imaging appearance does not involve a tortuous
vascular-appearing mass.

American Board of Pediatrics Content Specification:

       Identify the clinical features of CNS arteriovenous malformations of childhood
Question 25 (2009:230): A

The infant described in the vignette has an encephalopathy, a "confusional" state. It is critical
to consider focal, ischemic, ictal, infectious, and toxic/metabolic causes for any patient
presenting with mental status changes. The noncontrast head computed tomography scan and
laboratory tests were appropriate initial decisions in the emergency department to rule out
emergent, treatable problems. For this infant, the key to the diagnosis is recognition that the
cluster of body spasms combined with the loss of developmental milestones is characteristic of
infantile spasms, which should be assessed by electroencephalography (EEG). EEG is used to
identify the neurophysiologic pattern that confirms the diagnosis of infantile spasms. The
characteristic diffuse, slow, disorganized, and high-amplitude pattern is known as

Infantile spasms describes a syndrome of epilepsy and encephalopathy in infancy, with a peak
onset at 6 months. The spasms (Item C230) can range from subtle, quick movements
involving just the head to dramatic "clasp-knife" full body spasms. Infantile spasms can have a
number of causes or can be idiopathic. The prognosis is often poor, particularly if the child's
neurologic development was abnormal prior to the onset of spasms. Potential causes of the
infantile spasms may be structural, genetic, or metabolic.

Electroretinography (ERG) is used to assess the neurophysiology of the retina. For example,
ERG responses are abnormal in Leber congenital amaurosis and various rod/cone dystrophies.
This child's new visual impairment associated with hypotonia and spasms is not likely related
to retinal pathology, but more likely is due to a central nervous system problem causing
abnormal visual processing.

A lumbar puncture should be considered in an infant who has fever and an acute
encephalopathy to rule out infectious causes, but establishing the diagnosis of infantile spasms
is more important in this case. A lumbar puncture, if it is obtained, might be more valuable as
part of a metabolic evaluation, as would measurement of serum lactate and a muscle biopsy,
if needed to assess for the possibility of a mitochondrial disorder.

American Board of Pediatrics Content Specification:

       Recognize the characteristic clinical picture of infantile spasm

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