Application of the Continuous Glucose Monitoring System (CGMS ® ) in the 72-Hour Fast Test in Two Patients with Hypoglycemia

Abstract

Objective:

Hypoglycemia occurs in several pathologic states, and the supervised 72-h fast is the classic diagnostic test for hypoglycemia caused by insulinoma. The Continuous Glucose Monitoring System (CGMS^®, Medtronic MiniMed, Northridge, CA) is an appropriate method to detect asymptomatic hypoglycemia episodes in diabetes mellitus patients. In the present study, we use the CGMS to monitor glucose dynamics during a 72-h fast.

Methods:

Two patients with hypoglycemia disorders were admitted to the hospital for testing. The CGMS sensors were inserted into the subcutaneous tissue prior to starting a 72-h fast test. Finger stick glucose levels were taken every 3–4 h, and the data were entered into the monitor for calibration.

Results:

Paired glucose readings from CGMS and conventional meters were correlated significantly(P < 0.001, r² = 0.79). There was no significant difference between the CGMS glucose levels and conventional meter glucose levels (P > 0.05). Use of CGMS detected a high prevalence of asymptomatic hypoglycemia and two types of hypoglycemia dynamics during a 72-h fast test.

Conclusions:

This initial report using CGMS detected two types of hypoglycemia dynamics during 72-h fasting, which may provide clues to better understand the pathophysiology of hypoglycemia.