Which of the following symptoms can potentially indicate severe complications in Zollinger-Ellison syndrome?

Abdominal pain is a significant symptom that can indicate severe complications in Zollinger-Ellison syndrome, primarily due to the excessive secretion of gastric acid that characterizes this condition. Zollinger-Ellison syndrome involves gastrin-secreting tumors, often leading to peptic ulcers and related gastrointestinal issues. The high levels of gastric acid can result in intense abdominal pain as the acid irritates the lining of the stomach and intestines. Abdominal pain may also accompany complications such as perforation or hemorrhage of ulcers, making it a vital symptom to monitor in patients with this syndrome.

Other symptoms, although they may be present in patients with Zollinger-Ellison syndrome, do not specifically indicate the severity of the complications associated with it. Fatigue could be a result of various underlying conditions or even due to chronic pain or nutritional deficiencies from malabsorption related to excessive acid. Water retention is typically more associated with fluid and electrolyte imbalances, while cold intolerance usually does not have a direct connection to the gastrointestinal manifestations of Zollinger-Ellison syndrome. Thus, among the options provided, abdominal pain stands out as a key indicator of potential severe complications in this condition.