A 7-year-old boy presents to the nurse practitioner (NP) at the primary care provider's office accompanied by his mother. The mother requested an appointment today because she was concerned about her son's staring events reported by his school teachers. The child's mother reports that she has intermittently noticed these events at home, but she thought he was just "not paying attention." She indicated that he seems to respond after she calls his name once or twice. The mother reports that the teachers first mentioned frequent daydreaming and inattention during the end of the previous school year. He has continued to meet academic expectations, so no further concerns were raised.
History and physical exam reveal a generally healthy child who was born full term after a normal pregnancy and cesarean section delivery due to failed labor progression. He was healthy after birth and had a myringotomy tube placement for frequent otitis media in infancy. Early development was characterized by normal gross and fine motor skill achievement with a mild speech delay. He received early intervention, and speech was considered appropriate by 3 years of age. His only hospitalization was due to respiratory syncytial virus infection at 6 months of age. He has allergies, asthma, and eczema. He is up to date on his immunizations. He is an alert, interactive child with a normal neurologic exam.
What diagnoses are most consistent with this history?
Attention-deficit hyperactivity disorder (ADHD). ADHD is typically first recognized in preschool/school-age children. The features of ADHD are specifically outlined by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), and patients must meet these criteria for an ADHD diagnosis.1 Specifically, children with ADHD have difficulty staying on task even if the task is of interest to the child. Children with ADHD are frequently noted to have difficulties in school related to inattention. ADHD has multiple associated comorbidities, including behavioral dysregulation, cognitive delays, and hyperkinetic motor disturbances, such as tics.1-3
Inattention/"daydreaming." Inattention is most often first reported by teachers. It typically occurs during tasks that are less engaging for the child. It is unlikely to occur during play or activities the child enjoys. A primary distinguishing feature is that the events can be interrupted by touch. Unresponsiveness to only the voice is not uncommon in children with inattention. Inattention periods are usually brief but may last several minutes, particularly in children with developmental or cognitive delay.4
Seizures
Seizures can start in both cerebral hemispheres of the brain at the same time or in one cerebral hemisphere of the brain.
A seizure that starts in both hemispheres at the same time is a generalized seizure. Loss of consciousness is an absolute characteristic with this type of seizure. Generalized seizure types consist of tonic/clonic (convulsing of all extremities starting at the same time); atonic (loss of muscle tone characterized by a brief head drop or drop/fall to the ground); absence (characterized by brief staring and often eye fluttering, chewing/lip smacking mouth movements and hand automatisms); and myoclonic (brief jerking of bilateral extremities).5,6
A partial seizure starts in one cerebral hemisphere of the brain. Partial seizures can be either simple or complex. In a simple partial seizure, there is no altered level of consciousness. In a complex partial seizure, there will be loss of consciousness or altered level of consciousness. For example, the child may respond verbally during a seizure, but the response does not make sense.5
Staring can be a feature of complex partial seizures or absence seizures. There is almost always the presence of other features, such as jerking of one side of the body or one extremity as well as eye deviation or head deviation to one side, when present as part of a complex partial seizure.6 Eye fluttering and hand automatisms are often reported when staring is secondary to an absence seizure, but these seizures may also occur without these features.
Based on the current history and physical exam today of the child in the case study, an evaluation for ADHD is recommended as per the American Academy of Pediatrics.2 Diagnostic testing is not necessary as part of the initial evaluation for ADHD in an otherwise healthy child. The mother was given assessment tools to complete as well as a school evaluation. She was instructed to return the forms when complete and then to return for a follow-up visit in 6 months or sooner (if the mother has continued concerns about her son's inattention).
Follow-up
The child returns to the clinic approximately 6 months later. The assessments previously provided were returned, and while the child demonstrates frequent inattention, he is able to stay on task. His mother reports that he is having a decline in school performance, and his grades are now Cs and Ds. She reports that despite special accommodations in school, his staring has continued and possibly worsened. Teachers report frequent inattentiveness. This is noted multiple times per day at home and at school. His mother states that the episodes are more likely to occur when the child is tired or ill.
The physical exam performed by the NP is unchanged from the previous visit with one exception: The NP noted that while taking the history, the child had brief, 2- to 3-second episodes of rapid eye fluttering with upward gaze of the eyes and unresponsiveness to verbal and tactile stimuli. It is suspected that these may represent absence seizures.
To further diagnostically confirm this, voluntary hyperventilation is performed.4 Giving the child a pinwheel, he is asked to blow, making the pinwheel move continuously, for 3 minutes. Thirty seconds into the test, it is noted that the child has eye deviation upward with eye fluttering. The child's name is called with no response. He is then asked to recall the words "red car." The event lasts approximately 5 seconds, and the child immediately resumes previous activity. When asked, he does not recall the cue words "red car."
Discussion
Staring as a chief complaint can be challenging to diagnose in the clinical setting, as it may be a primary feature in several disorders. In the pediatric population, this primarily includes ADHD, inattention, and seizures, among others. It is important to determine the cause of staring prior to initiating treatment while reducing any unnecessary testing. There are several characteristic differences between seizures and the other common disorders discussed that are important in the clinical differential.
When described by teachers and parents, staring is often presumed to be inattention. A differentiating factor is the child's ability to stay on task. Children with absence seizures are commonly able to stay on task, while children with ADHD are typically reported to have difficulty with this.7 In a recent study, the ability to stay on task demonstrated favorable specificity and sensitivity to differentiate ADHD versus absence seizures.7
Childhood absence epilepsy occurs in 9.6 per 100,000 in ages 0 to 15 with average age of onset of 5.7 years.3 Associated clinical symptoms are almost always present with absence seizures, with only 16% having staring be the only feature.8 These are typically not present with staring related to other problems.8 These associated symptoms can include any of the following: eye fluttering, eyes deviated up, lip smacking movements, verbalizations (such as a humming sound), or hand automatisms (such as repetitively pulling at clothing). Although absence seizures are typically very brief (lasting up to 20 seconds), there is always a loss of consciousness during the seizure. Due to the brevity of the seizures, this loss of consciousness is not always obvious, and the child often resumes previous activities immediately following a seizure. If a cue word is provided during the seizure, the child will not be able to recall the word.3
Lack of response to tactile stimulus is commonly used, as it is an indicator for possible seizure. However, given the brief nature of absence seizures, this may not be a reliable tool for identification. A raised suspicion for seizures is warranted for events that are described as resulting in unresponsiveness to tactile stimulus. Caution is advised when considering lack of response to tactile stimulus as a primary diagnostic indicator.4
Hyperventilation-provoked events can be diagnostic of absence epilepsy.4 Studies have shown that hyperventilation provokes absence seizures in approximately 90% of children with childhood absence epilepsy.4 Approximately half of all children with any type of absence epilepsy will have a seizure provoked by voluntary hyperventilation.4 Hyperventilation can be performed with a patient in the clinical setting and is completed on a routine electroencephalogram (EEG) if the child is developmentally able to cooperate with the test. A routine EEG is recommended for confirmation of absence epilepsy.4 EEG reveals a 3 Hz generalized spike and wave abnormality in children with typical absence epilepsy.4 If a seizure disorder is suspected by the primary care provider, an order for a routine EEG may be placed if this is available to the provider. With this, a referral to a pediatric neurology specialist is warranted for appropriate treatment.
The child in the case study was seen by the pediatric neurologist who reviewed the routine EEG, which revealed a generalized spike and wave pattern at 3 to 3.5 Hz. Hyperventilation was performed, which provoked a generalized seizure noted on EEG with frontal dominant generalized spike and wave that coincided with the clinical manifestation of the child staring with rapid eye fluttering. This confirmed the diagnosis of generalized epilepsy - specifically absence epilepsy. Treatment with medication was recommended to reduce seizure frequency. Without medication treatment, the seizures will continue and become more frequent, putting the child at increased risk of having a prolonged seizure and continued learning difficulties.
Pinpointing the cause
In summary, staring events can represent multiple diagnoses and a detailed history and physical is vital for an accurate diagnosis and treatment. There are several variations of staring presentation that have been discussed that can be used in the primary care setting to facilitate differentiation among these diagnoses. Reevaluation and reassessment are recommended to determine and pinpoint the cause of staring if a child does not respond to the first intervention.
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