An 8-year-old boy is brought to the emergency department due to a staring episode this evening. While eating dinner, the parents first noticed the patient's head tilt to the right, followed by right arm twitching. The patient then began chewing his lips and picking at his shirt while staring straight ahead. He did not respond to his name or to touch. The episode lasted for 2-3 minutes, and the patient seemed confused and tired afterward. He had no incontinence during the event but was unable to move his right arm for 5-10 minutes afterward. The patient has no other medical conditions or allergies. He was previously doing well in school, but his grades have declined over the past few months, and his teacher has noted that he seems intermittently distracted. Vital signs are normal. Physical examination shows an awake and alert child. Cranial nerves are intact, and reflexes are 2+. Romberg test is negative. An interictal electroencephalogram is normal and does not change with hyperventilation. Which of the following is the most likely diagnosis in this patient?

Question

An 8-year-old boy is brought to the emergency department due to a staring episode this evening.  While eating dinner, the parents first noticed the patient's head tilt to the right, followed by right arm twitching.  The patient then began chewing his lips and picking at his shirt while staring straight ahead.  He did not respond to his name or to touch.  The episode lasted for 2-3 minutes, and the patient seemed confused and tired afterward.  He had no incontinence during the event but was unable to move his right arm for 5-10 minutes afterward.  The patient has no other medical conditions or allergies.  He was previously doing well in school, but his grades have declined over the past few months, and his teacher has noted that he seems intermittently distracted.  Vital signs are normal.  Physical examination shows an awake and alert child.  Cranial nerves are intact, and reflexes are 2+.  Romberg test is negative.  An interictal electroencephalogram is normal and does not change with hyperventilation.  Which of the following is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

11ec25c8_d5ca_b012_bc81_8d2a50df370d_MD0003_00 This patient likely had a focal seizure, which is defined as a seizure originating from a single hemisphere. Symptoms can involve motor (eg, twitching), sensory (eg, paresthesias), and/or autonomic (eg, sweating) activity. In this instance, the patient's initial abnormal movements of isolated right head tilt and arm twitch are consistent with a focal seizure. Focal seizures can also spread to involve both cerebral hemispheres and cause impaired awareness, as seen with this patient's subsequent staring episode and inability to respond to verbal or tactile stimuli. Repetitive, semipurposeful movements (eg, chewing, picking) called automatisms are often seen in focal seizures with impaired consciousness. Due to the impact on cognition, school-aged children with uncontrolled seizures or subtle seizure manifestations may also have a history of decline in academic performance. After a seizure, postictal confusion and lethargy are common, and transient postictal paresis or paralysis (Todd paralysis) may also occur, as seen in this patient. During a focal seizure, electroencephalogram (EEG) reveals abnormal electrical activity arising from a specific region in the brain, whereas interictal EEG is often normal. (Choice A) Absence seizures are generalized (ie, originating from both cerebral hemispheres) and present with staring spells, with or without automatisms, lasting only 10-20 seconds. In contrast to this patient, absence seizures are characteristically easily provoked by hyperventilation and not associated with a postictal period. (Choice C) Juvenile myoclonic epilepsy presents in adolescents with myoclonic jerks immediately on wakening. Absence and generalized tonic-clonic seizures may also be seen. This patient's age and focal seizure make this diagnosis unlikely. (Choice D) Lennox-Gastaut syndrome typically presents by age 5 with intellectual disability and severe seizures of varying types (eg, atypical absence, tonic). Interictal EEG demonstrates a slow spike-and-wave pattern. (Choice E) Tic disorders present as sudden, brief movements (eg, grimacing) or vocalizations. Consciousness is not impaired by tic disorders. Educational objective: Focal seizures originate in a single cerebral hemisphere and can spread to involve both hemispheres, causing impairment of awareness (with or without automatisms) and inability to respond to external stimuli. In contrast to absence seizures, focal seizures are associated with a postictal phase and are not provoked by hyperventilation. References: Operational classification of seizure types by the International League Against Epilepsy: Position Paper of the ILAE Commission for Classification and Terminology. (http://www.ncbi.nlm.nih.gov/pubmed/28276060)

An 8-Year-Old Boy Is Brought to the Emergency Department Due