Pediatric Examination and Board Review (15 page)

(B) respiratory effort during the event

(C) muscle tone during the event

(D) B and C only

(E) A, B, and C

12.
All of the following are clinical features of an ALTE that point to a seizure except

(A) relationship to feeding

(B) muscle tone during the event

(C) rhythmic movements during the event

(D) fever at the time of the event

(E) period of decreased responsiveness after the event

13.
In a child who presents with an ALTE, which of the following histories would be consistent with GE reflux as the underlying etiology?

(A) the mother reports arching of the back during the event

(B) the mother reports choking during the event

(C) the mother reports that the event happened just after feeding

(D) the mother reports frequent “spit-ups” after feeding

(E) all of the above

ANSWERS

1.
(A)
A seizure is a distinct possibility in a child with an ALTE. Metabolic derangements are common causes of seizures in this age group. Although hypomagnesemia may cause seizures, hypoglycemia, hypocalcemia, and hyponatremia are the 3 electrolyte disturbances most frequently associated with seizures. Therefore, it is imperative to obtain a serum glucose and electrolytes upon the child’s arrival in the emergency department.

2.
(A)
If the history and the initial lab work are not revealing, the evaluation should include a CT scan of the head, a chest radiograph, an ECG, and, perhaps, a lumbar puncture. Knowledge gained from a careful history of the event will direct the testing required and urgency of those tests. Detailed questioning should include the duration of the event, color change in the infant, respiratory efforts made by the child, and the intervention required for the episode to cease. Further questions should assess the child’s muscle tone, activity, the relationship of the episode to feeding, description of any episodes of emesis, choking or gasping, the presence of fever, and rhythmic movement of the extremities of the eyes. An understanding of the ambient lighting available to the observer may also be helpful. The presence of dried blood in the nose of this small child should prompt the clinician to consider the possibility that this is nonaccidental trauma. Further suspicion is suggested by the family history of SIDS. An EEG and, if available, a pH probe should be done after the urgent studies just described have been obtained. In a younger infant, intercurrent infections such as respiratory syncytial virus (RSV) should also be considered. If nonaccidental trauma is high on the list of possible etiologies, the workup for other concomitant trauma should be pursued with an ophthalmologic examination for retinal hemorrhage and a radiographic skeletal survey for occult fractures.

3.
(E)
An episode of ALTE in an infant is characterized by clinical symptoms that are sufficiently frightening to the caregiver, who believes the child may have experienced cardiac arrest or may die. These events generate substantial anxiety in the family and are also costly to the health-care system to evaluate fully. Although it a very common reason for admission to the hospital, the precise incidence and prevalence of ALTE in the United States are not known.

4.
(A)
SIDS has been defined by the National Institutes of Health as the sudden death of an infant or young child, that is “unexplained by history,” and in whom the autopsy fails to demonstrate a cause of death. The child who presents with an ALTE is no more likely to die subsequently from SIDS than are other children. However, SIDS is an important cause of death in infants. SIDS is the third leading cause of infant mortality following congenital abnormalities and disorders related to preterm gestation. The rate of SIDS in the United States has declined more than 50% in the last 20 years. The etiology of SIDS is still unknown, but dramatic decreases in the incidence of SIDS have been demonstrated across the world since warnings against prone positioning during sleep have been implemented. The peak incidence is at 3-5 months of age. Sleeping in the prone position clearly places infants at risk, as does young maternal age, low socioeconomic status, smoking in the house where the infant sleeps, and soft bedding. There is no association between apnea of prematurity and SIDS. Of note, fewer than 1% of children who have an ALTE go on to have any other event that is life challenging. The Back to Sleep campaign has made no impact on the incidence of ALTEs, further strengthening the assertion that these 2 diagnoses are not related. It is also important for the clinician to recognize that SIDS is not a familial event. Therefore, SIDS that recurs in a family should strongly suggest the possibility of abuse and homicide. The presence of dried blood in the child’s nose should heighten the clinician’s suspicion for nonaccidental trauma such as suffocation.

5.
(D)
Nearly all infants who experience an ALTE should be hospitalized for observation and evaluation. Polysomnography may be useful in the child with a negative initial evaluation and thus no identified etiology. When an etiology is discovered for the ALTE, treatment is easier than for those infants in whom no identifiable cause is found. The family history of a child with SIDS should lead the clinician to a thorough workup for nonaccidental trauma.

6.
(C)
Rib fractures are not a “normal” finding in infants. Fractures are generally not identified until callus has formed and therefore would not be seen immediately following resuscitative efforts. Posterior rib fractures found on radiography of the chest are further evidence of nonaccidental trauma, specifically a shaking injury. Anterior rib fractures are rare and usually do not result from anteriorposterior compression.

7.
(A)
Estimates suggest that nonaccidental trauma is responsible for 1-5% of so-called SIDS cases.

8.
(C)
Where no explanation for the inciting event can be found, many families raise the issue of home monitoring. Evidence for home monitoring to prevent consequences from an ALTE is nonexistent. In preterm infants with apnea of prematurity, home monitoring appears to be helpful until 43 weeks postconceptional age. Home monitoring may be disruptive to the family and should not be recommended after an ALTE.

9.
(D)
ALTE is not thought to be familial. Siblings only require routine care. So-called “familial” ALTE or SIDS should lead one to consider nonaccidental trauma as the cause.

10.
(A)
The differential diagnosis is broad and includes infection, particularly RSV and meningitis, gastroesophageal reflux disease (GERD), neurologic disorders such as seizures, or nonaccidental trauma, airway abnormalities, cardiac rhythm abnormalities such as prolonged QT, metabolic abnormalities, and Munchausen syndrome by proxy. The etiology in most ALTEs remains unknown even when exhaustively evaluated.

11.
(E)
Knowledge gained from a careful history of the event will direct the testing required and urgency of those tests. Detailed questioning should include inquiry about the duration of the event, color change in the infant, respiratory efforts made by the child, and the intervention required for the episode to cease. Further questions should assess the child’s muscle tone, activity, the relationship to feeding, episodes of emesis, choking or gasping, the presence of fever, and rhythmic movement of the extremities or the eyes.

12.
(A)
A child with symptoms after eating suggests a diagnosis of GERD.

13.
(E)

S
UGGESTED
R
EADING

Ferrell PA, Weiner GM, Lemons JA. SIDS, ALTE, apnea, and the use of home monitors.
Pediatr Rev.
2002;23(1):3-9.

Hall KL, Zalman B. Evaluation and management of apparent lifethreatening events in children.
Am Fam Phys.
2005;71(12):2301-2308.

CASE 7: A 4-MONTH-OLD WITH HYPOTONIA AND A WEAK CRY

A 4-month-old female infant is brought to the emergency department for poor feeding, a weak cry, and lethargy. There have been no other symptoms: no upper respiratory tract illness, no fever, no vomiting, or diarrhea. In fact, she has not had a bowel movement in 4 days. She normally takes approximately 6-8 ounces of formula at a time, but for the last few days she seems to tire after taking only 2 ounces. During the preceding 2 weeks, she has become less active. Her mother also reports that she can no longer hold her head up without support.

Her heart rate is modestly elevated at 130 beats per minute (bpm) and the remaining vital signs are normal. She has markedly diminished muscle tone. On physical examination, she seems alert but very quiet. The anterior fontanelle is soft. There are no murmurs. Breath sounds are normal. The abdominal examination is normal. Pupils are 3 mm in size and react to light bilaterally. She has generalized weakness with diminished gag and cough reflexes, a marked head lag, and diminished deep tendon reflexes.

SELECT THE ONE BEST ANSWER

1.
The most likely cause of this child’s weakness is

(A) Guillain-Barré syndrome

(B) amyotrophic lateral sclerosis

(C) polio

(D) infant botulism

(E) Werdnig-Hoffman disease

2.
The investigation(s) that is/are the most likely to lead to the appropriate diagnosis is

(A) serum creatinine kinase (CK) and aldolase

(B) CT scan of the head

(C) stool studies for bacterial toxin

(D) examination of CSF

(E) a blood culture

3.
An alternative diagnostic test that might be useful is

(A) EEG