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Insulinoma with early-morning abnormal behavior
Keisuke Suzuki1, Masayuki Miyamoto, Tomoyuki Miyamoto
1Department of Neurology, Dokkyo Medical University, Tochigi, Japan. keisuke@dokkyomed.ac.jp <keisuke@dokkyomed.ac.jp>
Internal Medicine (Tokyo, Japan)
|April 6, 2007
Summary
A 65-year-old man experienced unusual behaviors due to an insulinoma, a tumor causing low blood sugar. This case highlights hypoglycemia as a potential cause of complex nocturnal behaviors, mimicking sleep disorders.
Area of Science:
- Neuroendocrinology
- Clinical Medicine
Background:
- Insulinoma, a rare pancreatic tumor, can cause recurrent hypoglycemia.
- Hypoglycemia is known to manifest with a range of neurological and behavioral symptoms.
Observation:
- A 65-year-old male patient with insulinoma presented with progressive behavioral changes, including stereotypical and complex episodes occurring in the early morning.
- The patient experienced amnesia regarding these episodes.
- Diagnostic workup revealed fasting hypoglycemia (blood glucose 15 mg/dl) and elevated insulin levels, confirmed by a high insulin/glucose ratio (>0.3).
- Abdominal CT identified a tumor in the pancreatic head.
Findings:
- The patient's symptoms were directly linked to hypoglycemia induced by the insulinoma.
- The behavioral manifestations were complex and occurred during specific times, suggesting a link to circadian rhythms or sleep-wake cycles.
Implications:
- This case underscores the importance of considering insulinoma and resultant hypoglycemia in the differential diagnosis of unexplained nocturnal or early morning behavioral disturbances.
- The findings suggest that hypoglycemia can manifest with symptoms mimicking conditions like sleep-related epilepsy, parasomnia, and night delirium.
- Early diagnosis and management of insulinoma are crucial to prevent severe neurological and behavioral consequences.
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