Abstract
Context:
The supervised 72-h fast remains the gold standard test for the diagnosis of endogenous
hyperinsulinism and has recently been suggested to be shortened or even avoided.
Objective:
This study aimed to evaluate whether measurement of blood glucose, insulin and C-peptide
levels after a 12 h overnight fast (mini-fasting test), in at least 3 consecutive
days, could allow making or ruling out diagnosis of endogenous hyperinsulinism, according
to the Endocrine Society’s recent guidelines.
Patients and methods:
We performed 12 h mini-fasting test in at least 3 consecutive days, dosing blood glucose,
insulin and C-peptide levels in 26 inpatient patients with pathologically proven endogenous
hyperinsulinism.
Results:
In our series, 100% of patients showed insulin levels of at least 3 μU/ml and C-peptide
levels of at least 0.6 ng/ml concomitant with symptomatic hypoglycemia (≤55 mg/dl).
Conclusion:
It leads to the conclusion that mini-fasting test might avoid, in most cases, prolonged
fasting test for the diagnosis of hypoglycemia due to endogenous hyperinsulinism.
Key words
endocrine pancreas - hypoglycemia - insulinoma
