P3.216: The monster hunter:Unraveling a 5-year-old’s Hallucinations

Introduction: Acute visual hallucinations in young children, while less often caused by psychopathology compared to adolescents and adults, can cause significant distress and present diagnostic challenges. The differential diagnosis of neurobehavioral alterations includes trauma, sepsis, sleep deprivation, ingestion, hypoxia, and metabolic disturbances, such as hypoglycemia. The Pediatric Endocrine Society emphasizes that neuroglycopenic symptoms of hypoglycemia —resulting from insufficient glucose supply to the brain — include confusion, seizures, and coma. Behavioral changes and cognitive dysfunction are also well-documented manifestations of hypoglycemia. This case highlights a 5-year-old male presenting to a tertiary care children’s hospital with acute visual hallucinations, behavioral changes, and severe hypoglycemia.

Case Description: A 5-year-old male presented to the Emergency Department (ED) with a sudden onset of visual hallucinations. Per his mother’s report, the patient woke at 9:00 AM screaming and pointing at “monsters” on the wall. The mother was not overly concerned until 4 hours later when the behavior had still not abated. She noted that he had mildly decreased oral intake the day prior and had eaten poorly for breakfast on the day of the event- “1-2 bites” of pancakes. Initial vital signs were significant for tachycardia at 193 beats per minute. ED laboratory evaluation revealed blood glucose 36mg/dL, white blood cells of 16 x10^9/L with 72.8% neutrophils, ketones of 3.04 mmol/L, and bicarbonate of 13mmol/L. Testing for toxicological and infectious etiologies was negative. Head CT and EEG were normal. Insulin, c-peptide, growth hormone, and thyroid levels were normal. Diabetes-related antibodies were normal and HbA1c was 4.3%. Idiopathic Ketotic Hypoglycemia (IKH) diagnosis was established and managed with dietary modifications and glucose monitoring.

Discussion: Hallucinations are a rare but recognized manifestation of severe hypoglycemia. Idiopathic ketotic hypoglycemia, a common cause of fasting-induced hypoglycemia in young children, is a diagnosis of exclusion. While this patient’s autoimmune workup was negative, recurrent or fasting hypoglycemia may signify glucose dysregulation, potentially linked to early-stage Type 1 diabetes mellitus. Monitoring for the development of diabetes-associated autoantibodies is warranted in children with hypoglycemia. Comprehensive diagnostic evaluation during hypoglycemic episodes—including insulin and C-peptide levels, free fatty acids, beta-hydroxybutyrate, cortisol, growth hormone levels, and genetic testing—is essential to exclude endocrinopathies or metabolic disorders. Other helpful tests that can be obtained regardless of blood glucose value include Hgb A1c, C-peptide, free fatty acids, lactate, ammonia, and urine organic acids. Outpatient follow-up is often required to await results from autoantibody testing or specialized metabolic evaluations.

Conclusion: This case underscores the importance of considering hypoglycemia as a potential cause of visual hallucinations in children. Early recognition and treatment of hypoglycemia are critical to prevent permanent neurological damage. While this patient was diagnosed with IKH, he requires ongoing monitoring for the development of type 1 diabetes.