title: Assessing for Multiple Endocrine Neoplasia Type 1 in Patients Evaluated for Zollinger-Ellison Syndrome-Clues to a Safer Diagnostic Process.
abstract: BACKGROUND
  Zollinger-Ellison syndrome is a rare cause of tumoral hypergastrinemia; 1 of 5 patients with this syndrome also has multiple endocrine neoplasia type 1. The diagnosis of this disease is complicated by the widespread use of proton pump inhibitors that can elevate serum gastrin levels, the cornerstone for biochemical diagnosis. Abrupt discontinuation of proton pump inhibitors could lead to adverse outcomes. Clinician awareness of the relationship between Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1 could lead to a safer diagnostic pathway.
  
  
  METHODS
  We conducted a retrospective review of a cohort of patients with multiple endocrine neoplasia type 1.
  
  
  RESULTS
  There were 287 patients with multiple endocrine neoplasia type 1 (73 with gastrinoma) evaluated between 1997 and 2014. Two patients experienced adverse events after proton pump inhibitor therapy was discontinued to re-measure serum gastrin level during the evaluation of severe peptic ulcer disease. In both cases, the diagnosis of multiple endocrine neoplasia type 1 was made after proton pump therapy was discontinued.
  
  
  CONCLUSIONS
  Abrupt discontinuation of proton pump therapy can lead to adverse outcomes in patients with Zollinger-Ellison syndrome. Clinical assessment for features of multiple endocrine neoplasia type 1 (eg, serum calcium levels, personal and family history of hypercalcemia, pituitary or pancreatic tumors) could identify patients with higher risk for a tumoral source of hypergastrinemia where imaging studies can help support the diagnosis without the potential side effects of abrupt discontinuation of proton pump inhibitor therapy.
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida, Gainesville; Knowledge and Evaluation Research Unit in Endocrinology (KER-Endo), Division of Endocrinology, Diabetes, Metabolism and Nutrition, Department of Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: Naykky
authors.initials: N
authors.lastname: Singh Ospina
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: Diane
authors.initials: D
authors.lastname: Donegan
authors.affiliation: Knowledge and Evaluation Research Unit in Endocrinology (KER-Endo), Division of Endocrinology, Diabetes, Metabolism and Nutrition, Department of Medicine, Mayo Clinic, Rochester, Minn; Division of Endocrinology, Department of Internal Medicine, University Hospital "Jose E. Gonzalez", Autonomous University of Nuevo Leon, Monterrey, Mexico.
authors.forename: Rene
authors.initials: R
authors.lastname: Rodriguez-Gutierrez
authors.affiliation: Department of Surgery, Mayo Clinic, Rochester, Minn; Department of General Surgery, Cleveland Clinic, Ohio.
authors.forename: Zahraa
authors.initials: Z
authors.lastname: Al-Hilli
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Mayo Clinic, Rochester, Minn. Electronic address: wyoung@mayo.edu.
authors.forename: William F
authors.initials: WF
authors.lastname: Young
mesh_terms: D000328:Adult; D004381:Duodenal Ulcer / Q000188:drug therapy; D005260:Female; D005755:Gastrins / Q000097:blood; D005764:Gastroesophageal Reflux / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D018761:Multiple Endocrine Neoplasia Type 1 / Q000175:diagnosis*; D054328:Proton Pump Inhibitors / Q000627:therapeutic use; D012189:Retrospective Studies; D028761:Withholding Treatment; D015043:Zollinger-Ellison Syndrome / Q000097:blood / Q000175:diagnosis*
chemical_list: D005755:Gastrins; D054328:Proton Pump Inhibitors
keywords: Gastrin; Multiple endocrine neoplasia type 1; Proton pump inhibitors; Zollinger-Ellison syndrome