A Girl with Altered Mental Status and Hypoglycemia

Her blood glucose level was 30 mg/dl, and symptoms improved with glucose administration. Blood testing during hypoglycemia showed suppressed levels of insulin, pro-insulin, and C-peptide and no ketones. Pelvic fullness on exam prompted abdominal imaging, which revealed a large intraabdominal mass (see Figure 1, white arrows). After surgical resection of the mass, she was diagnosed with a rare paraneoplastic syndrome: hypoglycemia due to insulin-like growth factor II release by a benign smooth-muscle tumor.