Table 1.

Laboratory assessment of hypoglycemia.

	Case 1	Case 2
Plasma glucose (74–106 mg/dl)	34	54
Insulin (2–25 μU/l)	< 1	< 1
C peptide (0.78–5.19 ng/ml)	0.04	0.25
Proinsulin (3–20 pmol/l)	2.3	2.9
Beta hydroxybutyrate (0.2–2.81 mg/dl)	0.71	0.35
Insulin antibodies (0.00–0.02 nmol/ml)	0	0
Sulfonylurea screen	Negative	Negative
IGF-1 (108–167 ng/ml)	23	54
IGF-2 (288–736 ng/ml)	506	609
IGF-2/IGF-1 ratio	22	11.27