Febrile Seizure Case File

Febrile Seizure Case File

Eugene C. Toy, MD, Barry C. Simon, MD, Terrence H. Liu, MD, MHP, Katrin Y. Takenaka, MD, Adam J. Rosh, MD, MS

Case 34

A 16-month-old child is brought in by EMS after a witnessed tonic-clonic event at home by his mother. The mother, a 33-year-old G2 woman, reports that he was born vaginally at term after an uneventful pregnancy. His birth weight was 3700 g, and he was discharged on the second hospital day. The mother noted that the child has been well appearing, is not taking any medications and there had been no recent travel. He had been active for the past week with no apparent complaints. The mother thinks the seizure lasted about 5 minutes but it ceased by the time EMS arrived at the home. The vital signs on the chart include a temperature of 38.4°C (101.1°F) (rectal), a heart rate of 130 beats per minute, a respiratory rate of 24 breaths per minute, and a systolic blood pressure of 100 mm Hg. On initial evaluation, the child is well appearing, well-perfused, and in no respiratory distress. His mental status is back to baseline per the mother, and on further evaluation, the child has no rashes or murmurs but is noted to have a bulging erythematous tympanic membrane. Acetaminophen is ordered and the child is observed and reevaluated several times over the next couple of hours. No laboratory studies are ordered initially.

⯈ What is the most likely diagnosis?

⯈ What is the next step in management of this patient?

ANSWER TO CASE 34:

Febrile Seizure

Summary: This is a 16-month-old child with a febrile seizure and acute otitis media. The combination of a relatively brief seizure in a febrile child in this age group who awakens back to baseline is consistent with a diagnosis of febrile seizure. Uncomplicated presentations require a thorough history and physical examination but rarely any additional testing. The presence of a focal infection like otitis media is common but not essential for the diagnosis. Providing the child returns to a baseline playful state, admission to the hospital is not necessary.

• Most likely diagnosis: Simple febrile seizure and acute otitis media
• Next step in management: Medication to reduce the fever followed by a period of observation and reevaluation

ANALYSIS

Objectives

1. Learn the specific definition of a simple febrile seizure
2. Understand current standards for an age-based approach to the evaluation of a simple febrile seizure in the pediatric patient.
3. In cases of concurrent infection, specifically otitis media (OM), determine the need for further evaluation and/or testing in a simple febrile seizure.

Considerations

This infant has experienced a witnessed seizure at home and is noted to be febrile but well appearing and back at his baseline in the emergency department, and without neurologic deficits. As with all sick emergency department patients the evaluation begins with assessment of airway, breathing, and circulation. After the initial assessment, resuscitation and stabilization, etiology for the seizure must be investigated. This subject can be complex considering the large number of potential causes. The greatest immediate threat and concern is the possibility of CNS infection. Infectious causes must be addressed before less acute etiologies are considered.

Approach To:

Febrile Seizures

DEFINITIONS

SIMPLE FEBRILE SEIZURE: The definition for a simple febrile seizure is very specific: age between 6 months and 60 months, generalized tonic-clonic convulsions, spontaneous cessation of convulsion within 15 minutes, return to alert mental status after convulsion, documentation of fever (>38.0°C), one convulsion with a 24-hour period, and absence of neurologic abnormality on examination.

COMPLEX FEBRILE SEIZURE: This heterogeneous group is beyond the scope of this chapter. The causes, presentations, assessments, and treatments are broad and complex. A standard treatment recommendation does not exist and the clinician must evaluate and treat the child with a complex febrile seizure on a case-by-case manner.

WELL-APPEARING INFANT: An infant who appears to both caretaker and health care practitioner to interact appropriately for age, has no increased work of breathing, has normal skin color, and no evidence of dehydration on the clinical examination.

ACUTE OTITIS MEDIA: Bacterial (suppurative) infection of middle ear fluid indicated by acute onset of signs and symptoms accompanied by a middle ear effusion.

CLINICAL APPROACH

A simple febrile seizure is a traumatic event for the caregiver, and in almost all cases, the child will be brought in by ambulance, with the emergency medicine physician evaluating the patient after the tonic clonic activity has ceased. If the child does not appear toxic, distressed, or hemodynamically unstable, a period of observation is recommended. During this period (usually under 1 hour), the clinician should have a discussion with the caregiver and EMS regarding the duration of the event, recent illnesses, and new medications. Additional useful history includes any possible exposures to chemicals or medications in the household and if there exists a family history of seizure disorders. Also, documentation of a fever greater than 38.0°C should be obtained, and antipyretic medications can be administered (oral or rectal based on the infants mental status).

A thorough physical examination should be performed, looking specifically for any source of infection and clinical signs that are worrisome for bacterial meningitis (petechial rash, nuchal rigidity, failure to fully engage or to return to baseline level of awareness, etc). The child’s entire body should be examined for any signs of trauma or abuse such as old ecchymoses, scratches, or scars. The provider should observe the interaction between the child and care giver to raise or lowers ones suspicion for possible abuse.

For infants that meet the strict definition of a simple febrile seizure, further testing (serum electrolytes, glucose, lumbar puncture, and neuroimaging) is not warranted. Multiple retrospective studies have demonstrated the extremely low incidence of bacterial meningitis in children with a simple febrile seizure and no clinical signs of meningitis. Unfortunately, since the clinical presentation of bacterial meningitis can be more subtle in children younger than 12 months of age, some experts recommend lumbar puncture even for simple febrile seizures in this population (6 months to 12 months).

Infants with concurrent infections (bacterial enteritis, urinary tract infection, or otitis media) with a simple febrile seizure should be treated for the underlying illness, not changing the standard management. This child was found to have a case of acute otitis media (AOM).

Acute Otitis Media

The diagnosis of AOM requires a middle ear effusion and signs of middle ear inflammation. The disease exists on a spectrum with otitis media with effusion, which lacks a bacterial infection or inflammation. Diagnosis of a middle ear effusion can be confirmed on otoscopy by finding bubbles or an air-fluid level and a tympanic membrane that is abnormally colored (not translucent), opaque, and/or not mobile with pneumatic pressure. Acute inflammation can either be confirmed by a history of fever and ear pain (or tugging) or direct visualization of a bulging and red tympanic membrane.

Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis are thought to cause over 90% of cases of AOM; however, current vaccine patterns may alter future etiologies. Complications of AOM are rare, but include hearing loss, tympanic membrane perforation, and mastoiditis. Of most concern in this case would be the rare complication of intracranial extension causing meningitis, brain abscess, or central venous thrombosis. These complications must be entertained if AOM is encountered in the setting of a seizure, especially if the child experienced a complex febrile seizure.

There exists much controversy over when to treat AOM with antibiotics. Most professional guidelines recommend any child younger than the age of 2 be treated with antibiotics and children older than the age of 2 may be treated with a “watchful waiting” approach if they have mild or moderate symptoms. Amoxicillin remains the drug of choice. The widespread use of antibiotics in the developed world is widely thought to be responsible for the low incidence of severe complications of AOM seen in the ED.

Risk of Seizure Recurrence

One-third of children who have a simple febrile seizure will experience another by the age of 6 years old. Children who experience a simple febrile seizure have a small increase in their likelihood of developing epilepsy, but the risk is still only 1% in children that have had a simple febrile seizure.

Prevention and Treatment

Antibiotic and/or antipyretic therapy has not been shown to decrease the recurrence rates of simple febrile seizures. Caretakers can often feel overwhelmed in an effort to reduce the fever to prevent another seizure and must be reassured that such measures have not been shown to reduce recurrence. Continuous antiepileptic medications (eg, valproic acid, phenobarbital, etc.) are not recommended for first-time febrile seizures.

Case Resolution

The toddler discussed above is observed in the emergency department for 1 hour. He is noted to be playful, active, and in no distress. After a careful physical examination, the child is discharged home with his mother to follow-up with his pediatrician. Parents should be instructed to return to the emergency department immediately for repeat seizure, change in behavior, vomiting, etc. An expectation should be shared that the AOM should improve within 72 hours of antibiotic treatment, and if not, they should return to their pediatrician or the emergency department. As with any pediatric patient, an attempt should be made to contact the patient’s primary pediatrician prior to leaving the ED.

COMPREHENSION QUESTIONS

34.1 A 2-year-old toddler is brought in by her family after a seizure episode today. The family states that the child was in her normal state of health when they noticed her entire body jerking rhythmically for several minutes, during which she did not respond to their voice. After 1 hour, the child remained somnolent and minimally responsive at home and was brought to the ED for evaluation. The mother states the infant was coughing and having clear nasal discharge for the past 24 hours, but otherwise well. The mother, a 26-year-old G4 woman, reports that the toddler was born vaginally at term after an uneventful pregnancy. His birth weight was 3100 g, and he was discharged on the second day. The mother states the child received his 2-month vaccinations and has been feeding well today. The vital signs on the chart include a temperature of 39.0°C (102.2°F) (rectal), a heart rate of 140 beats per minute, a respiratory rate of 30 per minute, and a systolic blood pressure of 80 mm Hg. On the initial evaluation (about 30 minutes after the child is brought to the emergency department), the child is somnolent and not at baseline mental status per the mother. Further evaluation finds no physical examination abnormalities other than mild clear nasal discharge. The child has a normal cardiac, lung and skin examination. Which of the following criteria indicates this was a complex febrile seizure?

A. Age of the child involved

B. Height of the fever

C. Generalized tonic-clonic nature of the seizure

D. Lack of return to baseline mental status after convulsion

E. Preceding upper respiratory infection symptoms

34.2 A 16-month-old child is brought in by EMS after an episode of shaking visualized by mother that lasted 3 minutes. On arrival to the ED, the child is back to baseline mental status as per mother. The mother states the infant was coughing for the past 24 hours, but otherwise well. The mother, a 22-year-old G1 woman, reports that he was born vaginally at term after an uneventful pregnancy. The mother states the child received his 2-month vaccinations and has been playful and active but was noted to have a mild nonproductive cough for 2 days. The vital signs on the chart include a temperature of 39.3°C (102.7°F) (rectal), a heart rate of 150 beats per minute, a respiratory rate of 34 breaths per minute, and a systolic blood pressure of 80 mm Hg. On the initial evaluation, the child is well appearing, well perfused, and in no respiratory distress. The child has a normal cardiac, pulmonary, and has no rashes. Discharge instructions to the parent of the above toddler should include:

A. Recommended use of around-the-clock antipyretic therapy

B. Recommend beginning continuous anticonvulsive medications to prevent development of epilepsy.

C. Outpatient neurologic testing including electroencephalography

D. Rectal diazepam if the child becomes febrile again to prevent further seizures

E. Appropriate follow-up with the toddler’s pediatrician and reassurance

34.3 A 36-month-old toddler is brought in by EMS after an episode of shaking visualized by mother that lasted 12 minutes. On arrival to the ED, the child is resting comfortable in the bed with his mother. The mother states the toddler was tugging at his left ear and coughing for the past 2 days, but otherwise well. The mother, a 31-year-old G4 woman, reports that he was born vaginally at term after an uneventful pregnancy. The toddler has received all of his vaccinations and never had a seizure in the past. The vital signs on the chart include a temperature of 38.4°C (101.1°F) (rectal), a heart rate of 140 beats per minute, a respiratory rate of 22 per minute, and a systolic blood pressure of 110 mm Hg. On the initial evaluation, the child is well appearing, well perfused, and in no respiratory distress. The oropharynx is injected with injected pharyngeal tonsils. The left tympanic membrane is erythematous and nonmobile during air insufflation. The child has a normal cardiac, pulmonary, and has no rashes. What is the most appropriate management of the toddler?

A. Obtain laboratory testing (CBC) to determine the presence of an underlying infection

B. Neuroimaging to determine the presence of an underlying CNS infection

C. Treatment of the otitis media (OM) with conservative therapy (NSAIDs) and instructions to follow up with the child pediatrician in 24 hours

D. Lumbar puncture to determine a meningeal infection

E. Inpatient admission for ENT consultation

ANSWERS

34.1 D. A simple febrile seizure is characterized by strict criteria. If the child does not return to their baseline mental status shortly after convulsion, even in the setting of fever, it is considered a complex febrile seizure, and alternative causes must be explored.

34.2 E. Research has shown that a simple febrile seizure cannot be prevented by antipyretics or antiepileptics. After a first occurrence, the risk of future epilepsy is low, and no action need be taken initially as long as the symptoms fit the strict criteria for simple febrile seizure.

34.3 C. This patient had a simple febrile seizure so there is a very low suspicion for a direct extension of the acute otitis media into the intracranial space. The AOM is the cause of the fever and likely related seizure. Given the patient is over 2 years old, expert recommendations endorse a watchful waiting

approach to treatment. An alternative acceptable approach would be

to provide antibiotics from the ED, but still ensure close follow-up with the

patient’s pediatrician.

References

American Academy of Pediatrics Subcommittee on Management of Acute Otitis Media. Diagnosis and management of acute otitis media. Pediatrics. 2004;113:1451. 

Febrile seizures: clinical practice guideline for the long-term management of the child with simple febrile seizures. Pediatrics. Jun 2008;121(6):1281-1286. 

Fetveit A. Assessment of febrile seizures in children. Eur J Pediatr. Jan 2008;167(1):17-27. 

Hampers LC, Spina LA. Evaluation and management of pediatric febrile seizures in the emergency department. Emerg Med Clin North Am. Feb 2011;29(1):83-93.

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