Zollinger-Ellison syndrome

Synonyms

1

Overview

Zollinger-Ellison syndrome is a rare condition in which one or more tumors form in your pancreas or the upper part of your small intestine (duodenum). These tumors, called gastrinomas, secrete large amounts of the hormone gastrin, which causes your stomach to produce too much acid. The excess acid then leads to peptic ulcers, as well as to diarrhea and other symptoms.

The primary tumor is usually located in the pancreas, duodenum or abdominal lymph nodes, but ectopic locations have also been described (e.g., heart, ovary, gallbladder, liver, kidney).

Symptoms

Patients with Zollinger–Ellison syndrome may experience abdominal pain and diarrhea. The diagnosis is also suspected in patients without symptoms who have severe ulceration of the stomach and small bowel, especially if they fail to respond to treatment.[citation needed]

  • Chronic diarrhea, including steatorrhea (fatty stools)
  • Pain in the esophagus, especially between and after meals at night
  • Nausea
  • Wheezing
  • Vomiting blood (digested blood)
  • Malnourishment
  • Loss of weight due to loss of appetite

Gastrinomas may occur as single tumors or as multiple, small tumors. About one-half to two-thirds of single gastrinomas are malignant tumors that most commonly spread to the liver and lymph nodes near the pancreas and small bowel. Nearly 25 percent of patients with gastrinomas have multiple tumors as part of a condition called multiple endocrine neoplasia type I (MEN I). MEN I patients have tumors in their pituitary gland and parathyroid glands, in addition to tumors of the pancreas

Causes

Zollinger–Ellison Syndrome is caused by a non–beta islet cell (islet of Langerhans), gastrin-secreting tumor of the pancreas that stimulates the acid-secreting cells of the stomach (parietal cells) to maximal activity, with consequent gastrointestinal mucosal ulceration.

ZES may occur sporadically or as part of an autosomal dominant familial syndrome called multiple endocrine neoplasia type 1 (MEN 1). 

Prevention

There are no current guidelines to prevent Zollinger-Ellison syndrome. If you have a family history of Zollinger-Ellison syndrome or MEN 1, consider contacting a genetic counselor for screening.

Diagnosis

Clinical suspicion of Zollinger–Ellison syndrome may be aroused when the above symptoms prove resistant to treatment, when the symptoms are especially suggestive of the syndrome, or endoscopy is suggestive. The diagnosis of Zollinger–Ellison syndrome is made by several laboratory tests and imaging studies.

  • Secretin stimulation test, which measures evoked gastrin levels
  • Fasting gastrin levels, on at least three separate occasions
  • Gastric acid secretion and pH. Normal basal gastric acid secretion is less than 10 mEq/hour, while in Zollinger–Ellison syndrome it is usually more than 15 mEq/hour.
  • An increased level of chromogranin A is a common marker of neuroendocrine tumors

In addition, the source of the increased gastrin production must be discovered. This is either done using MRI or somatostatin receptor scintigraphy, the investigation of choice

There is not a genetic test specifically for Zollinger-Ellison syndrome (ZES), which usually occurs sporadically as a result of a tumor that secretes gastrin (a gastrinoma). However, genetic testing is available for multiple endocrine neoplasia type 1 (MEN1), which is a genetic condition present in about 25-30% of people with ZES.

Treatment

Proton pump inhibitors (omeprazole, and lansoprazole) and histamine H2-receptor antagonists (such as famotidine and ranitidine) are used to slow down acid secretion. PPI and H2 antagonist are relatively ineffective for pharmacologic treatment. Octreotide is the best drug for pharmacologic management. Cure is only possible if the tumors are surgically removed, or treated with chemotherapy.

Resources

See Research Publications