Abdominal pain
Ref:
Uptodate
[ Clinical manifestations and diagnosis of Zollinger-Ellison syndrome (gastrinoma)]
Harrison
[ 607]
Epocrates
[ https://online.epocrates.com/diseases/8031/Peptic-ulcer-disease/Diagnostic-Approach]
Epocrates
[ online.epocrates.com/diseases/8031/Peptic-ulcer-disease/Diagnostic-Approach]