Pediatric Examination and Board Review (225 page)

5.
(B)
This child most likely has complex partial seizures with secondary generalization given the single generalized tonic-clonic seizure and clinical history. The “strange feeling” likely represents an aura or a simple partial seizure. Simple partial seizures can precede complex partial seizures. Complex partial seizures are distinguished from simple partial seizures in that the patient has loss of consciousness with the former. In contrast to partial seizures, an aura is not observed in primary generalized seizures, such as absence epilepsy. Automatisms, such as lip smacking, can be observed during the period of altered consciousness. An EEG will most likely demonstrate anterior temporal spikes between seizures.

6.
(C)
This child most likely has an acquired epileptiform aphasia, such as Landau-Kleffner syndrome (LKS). LKS often occurs between the ages of 5 and 7 years. Children afflicted with LKS typically develop an abrupt or gradual loss of language ability. Expressive and receptive language dysfunction is observed. These children can also have behavioral and psychomotor disturbances, such that they resemble an autistic child. The EEG most commonly demonstrates sharp wave and spike-wave activity over the temporal or parietal-occipital regions bilaterally more commonly observed during sleep, which is most likely to be captured with 24-hour long-term video EEG monitoring. Electrical status of slow-wave sleep is a condition similar to LKS in which spike-wave activity is the dominant pattern observed during sleep. This disorder occurs with a peak age of onset between 4 and 5 years of age. The prognosis for both conditions is variable. Although some may recover fully, others continue to have speech and cognitive impairments. To capture slow-wave sleep (stage 4), a 24-hour EEG is usually required. MECP2 gene mutation is associated with Rett syndrome.

7.
(A)
If a child is seizure free for approximately 2 years, there is about a 70% chance the child will go into remission. Generalized seizures, a normal neurologic examination, and age of onset before approximately 12 years predict a more favorable outcome. Some studies suggest that a normal EEG or resolution of interictal spikes also predicts a favorable outcome.

8.
(B)
It is generally accepted among pediatric neurologists and neonatologists that phenobarbital is the firstline therapy for neonatal seizures, and phenytoin is the second-line therapy. Although many centers prefer to use fosphenytoin, a benzodiazepine is considered third-line therapy. Caution must be exercised when using phenobarbital in conjunction with a benzodiazepine because respiratory suppression, a potential side effect of both medications, is more likely.

9.
(E)
The most common form of childhood seizures are febrile seizures, occurring in 2-4% of the population in the United States.

10.
(E)
Children with epilepsy occasionally have comorbid conditions such as ADHD, depression, and tics. Many of the medications used to treat these comorbid conditions, such as methylphenidate, fluoxetine, risperidone, and haloperidol, can lower the seizure threshold. Atomoxetine, a selective norepinephrine reuptake inhibitor used to treat ADHD, does not seem to lower the seizure threshold. Although noncompliance with antiepileptic medications is always a concern in the treatment of pediatric epilepsy, the fact that the child went 18 months without a clinical seizure before initiation of methylphenidate makes it less likely this was an issue.

11.
(E)
Febrile seizures are considered complex if they are prolonged, lasting more than 10-15 minutes, are focal, or occur multiple times per febrile illness. Risk factors for a first febrile seizure include developmental delay, admission to the neonatal intensive care unit for longer than 30 days, attendance at day care, and having a family history of febrile seizures in a first- or second-degree relative. Based on data obtained from several large studies of children with febrile seizures, the risk of developing subsequent epilepsy is approximately 2-10%. Although treating febrile seizures remains controversial, daily phenobarbital has been shown effective in reducing the risk of recurrent febrile seizures. Diazepam given orally or rectally at the onset of a febrile illness reduces the probability of a febrile seizure. Carbamazepine and phenytoin are
not
effective in the treatment of febrile seizures.

12.
(E)
The causes of neonatal seizures are diverse and must be investigated to ensure adequate treatment. For example, seizures resulting from hypoglycemia require adequate glucose replacement.

13.
(B)
Stevens-Johnson syndrome secondary to lamotrigine administration occurs in 1-2% of children and 0.1% of adults. Other side effects of lamotrigine include dizziness, diplopia, and blurred vision.

14.
(C)
Fatal hepatotoxicity can occur in children treated with valproic acid. Children between the ages of 0 and 2 years are particularly at risk: 1 in 118,000 for patients on monotherapy and 1 in 800 on therapy with multiple anticonvulsants. Other side effects of valproate include weight gain in some children and thrombocytopenia.

15.
(A)
Long-term administration of phenytoin has been associated with gingival hyperplasia, hirsutism, acne, and rash (Stevens-Johnson syndrome). Toxic serum levels of phenytoin may result in ataxia, nystagmus, diplopia, and incoordination.

16.
(E)
Although serious hematologic complications with carbamazepine therapy are very rare, thrombocytopenia, aplastic anemia, agranulocytosis, and pancytopenia have been reported. Drowsiness, ataxia, dyskinesia, dizziness, and visual disturbances may also be observed.

17.
(F)
Behavioral side effects, especially hyperactivity and aggressiveness, can be seen in almost half the children taking phenobarbital. Dose-dependent side effects include sedation and respiratory depression.

18.
(D)
Weight loss has been reported as a side effect of topiramate therapy, usually beginning during the first few months of administration and peaking at 12-18 months.

S
UGGESTED
R
EADING

Baram TZ. Myoclonus and myoclonic seizures, and infantile spasms. In: Swaiman KF, Ashwal S, Ferriero DM, eds.
Pediatric Neurology: Principles & Practice.
4th ed. Philadelphia, PA: Mosby; 2006:1063.

Conway JM, Kriel RL, Birnbaum AK. Antiepileptic drug therapy in children. In: Swaiman KF, Ashwal S, Ferriero DM, eds.
Pediatric Neurology: Principles & Practice.
4th ed. Philadelphia, PA: Mosby; 2006:1105.

Holmes GL. Generalized seizures. In: Swaiman KF, Ashwal S, Ferriero DM, eds.
Pediatric Neurology: Principles & Practice.
4th ed. Philadelphia, PA: Mosby; 2006:1019.

Shinnar S. Febrile seizures. In: Swaiman KF, Ashwal S, Ferriero DM, eds.
Pediatric Neurology: Principles & Practice.
4th ed. Philadelphia, PA: Mosby; 2006:1079.

Wyllie E, ed.
The Treatment of Epilepsy: Principles & Practice.
4th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005.

CASE 132: A 5-MONTH-OLD BOY WITH SEIZURES AND A BIRTH MARK

You are called to the emergency department to evaluate a 5-month-old infant boy who presents with the chief complaint of “unusual leg movements” on awakening. The patient was born at full term by normal spontaneous vaginal delivery. The pregnancy was unremarkable except for maternal spotting in the first trimester. Developmentally, his mother states he is not yet rolling over. He startles to loud noises and occasionally vocalizes. Although he smiled responsively at 2 months of age, she has noticed he no longer seems to smile. His mother states that he often “spits up” after feeds. There is no family history of seizures.

During the evaluation, you observe a cluster of spells as the baby awakens. The spells consist of flexion of the head and body with extension of the legs. You are unable to stop the movements by applying gentle pressure. The baby was given a bottle feed approximately 1 hour ago.

On physical examination, his temperature is 98.2°F (36.8°C), the heart rate is 164, the respiratory rate is 32, and the blood pressure is 78/51 mm Hg. The tympanic membranes are normal. He has an irregular heartbeat. His lungs are clear to auscultation. Examination of his skin reveals 3 hypopigmented lesions over his abdomen and back. On neurologic examination, his tone is decreased centrally. He has a poor response to traction with a significant head lag. His reflexes are brisk symmetrically. His plantar reflexes are extensor.

SELECT THE ONE BEST ANSWER

1.
An echocardiogram is most likely to reveal which of the following diagnoses?

(A) cardiac rhabdomyoma

(B) fibroma

(C) teratoma

(D) myxoma

(E) hemangiomas

2.
The EEG demonstrates hypsarrhythmia; the head CT reveals periventricular calcifications. A small mineralized subependymal nodule is also observed. The most likely diagnosis is which of the following?

(A) Fahr disease

(B) neurofibromatosis (NF) type 1

(C) tuberous sclerosis complex (TSC)

(D) toxoplasmosis

(E) incontinentia pigmenti achromians (hypomelanosis of Ito)

3.
This patient is at risk for developing which of the following complications?

(A) hydrocephalus

(B) renal cell carcinoma

(C) bony involvement

(D) giant cell astrocytoma

(E) all of the above

4.
Which of the following is considered the most effective in the treatment of this patient’s seizure?

(A) topiramate

(B) phenobarbital

(C) primidone

(D) adrenocorticotropic hormone (ACTH)

(E) phenytoin

5.
Which of the following statements is true regarding the genetics of TSC?