Diagnosis of Zollinger-Ellison syndrome. From symptoms to biological evidence.

With insulinoma, Zollinger-Ellison syndrome is one of the most common functional islet-cell tumour. Since it is a life-threatening condition, needing appropriate management, the diagnosis must be accurately established. This paper reviews the clinical situations leading to suspect the diagnosis and the biological tests, mainly the secretin test, that confirm the diagnosis. The different ways of performing the secretin test and the respective results are presented. This review will also focus on some aspects of the diagnosis of multiple endocrine neoplasia type 1 in these patients.