Selective Arterial Calcium Stimulation With Hepatic Venous Sampling in Immune-Mediated Hypoglycemia

Area of Science:

• Endocrinology
• Gastroenterology
• Diagnostic Imaging

Background:

• Immune-mediated hyperinsulinemic hypoglycemia is a rare condition.
• Distinguishing it from pancreatic causes is crucial for treatment.
• Selective arterial calcium stimulation (SACS) with hepatic venous sampling is used to diagnose hyperinsulinemic hypoglycemia.

Purpose of the Study:

• To review the biochemical results of SACS with hepatic venous sampling in patients with immune-mediated hyperinsulinemic hypoglycemia.
• To compare these results with known responses in pancreatic causes of hypoglycemia.

Main Methods:

• Retrospective review of four patients with immune-mediated hyperinsulinemic hypoglycemia.
• SACS with hepatic venous sampling performed between January 1996 and March 2014.
• Comparison of baseline and post-calcium injection insulin concentrations in systemic and hepatic veins.

Main Results:

• Elevated baseline insulin concentrations were observed in all sampled vessels.
• No significant absolute or relative increase in hepatic venous insulin concentration occurred after calcium stimulation.
• This lack of response differentiates immune-mediated hypoglycemia from pancreatic causes.

Conclusions:

• Biochemical responses to SACS differ between immune-mediated and pancreatic hyperinsulinemic hypoglycemia.
• SACS with hepatic venous sampling may help differentiate the causes of hyperinsulinemic hypoglycemia.
• Further research is needed to validate these findings.