A five-year-old previously healthy bilingual (English and Spanish) boy presented to the ED with his parents due to insomnia for the previous two nights. The family history was negative for neurologic or psychiatric illness. The patient was a typically developing child born after a full term uncomplicated gestation and delivery. He had no prior history of injury, ingestion, psychosocial stressors, change in appetite, involuntary movements, or seizures. One week prior to presentation to the ED, he had been evaluated by his primary care physician after a three-day febrile illness and was diagnosed with a viral infection. Since that time, he had become more irritable and fussy, frequently having outbursts of crying without being able to articulate why he was crying. His father was concerned that he seemed scared during these episodes and was concerned about eye pain.
The patients' initial physical examination revealed normal vital signs, cardiovascular, pulmonary, and abdominal findings. He did not have dysmorphic features or a rash. Neuropsychiatric examination revealed an emotionally labile child with periods of calm and seemingly appropriate bilingual language development and behavior for age with episodes of extreme distress during which he would burst into tears and require physical restraint by family members against combativeness. Examination of the cranial nerves, motor tone, strength, coordination, and gait were normal and there was no sign of meningismus on physical examination.
Initial differential for this clinical presentation was broad including insomnia secondary to pain from corneal abrasion or other unidentified traumatic or infectious source, traumatic brain injury, thyrotoxicosis, developmental disorder with regression, encephalopathy due to acute intoxication, acute psychosis, postinfectious or parainfectious encephalitis, and autoimmune encephalopathy. Screening in the ED with urine drug screen, serum acetaminophen and salicylate levels, complete blood count, complete metabolic panel, thyroid function tests, inflammatory markers, urinalysis, head CT scan, and EKG all revealed normal results. PCR respiratory panel (nasal swab) was negative for frequently tested viral and bacterial pathogens including negative for mycoplasma pneumoniae. The patient was admitted to the general pediatrics service with support from consulting services for further evaluation and management given his altered mental status and concern for acute encephalopathy.