Zollinger-Ellison Syndrome

Zollinger-Ellison syndrome (ZES) is a rare medical condition characterized by the excessive production of gastric acid in the stomach, leading to severe and recurrent peptic ulcers.

Causes

The primary cause of ZES is a non-beta cell tumor of the pancreas, known as a gastrinoma. This tumor secretes high levels of gastrin, a hormone that stimulates the parietal cells in the stomach to produce excessive amounts of gastric acid.

Gastrinomas

Gastrinomas are typically found in the duodenum (the first part of the small intestine) or the pancreas. They can be benign or malignant, and may occur as a single tumor or as multiple tumors.

Symptoms

The symptoms of ZES include:

• Severe and recurrent peptic ulcers in the stomach and duodenum
• Abdominal pain, often severe and burning in nature
• Nausea and vomiting, which may be bloody
• Diarrhea, which can lead to weight loss and malnutrition
• Gastroesophageal reflux disease (GERD)

Diagnosis

The diagnosis of ZES is based on a combination of clinical presentation, laboratory tests, and imaging studies. The following tests may be used to diagnose ZES:

• Upper endoscopy to visualize the stomach and duodenum
• Biopsy of the stomach or duodenum to examine for ulcers and gastrinomas
• Measurement of serum gastrin levels, which are typically elevated in ZES
• Secretin stimulation test to assess the response of gastrin secretion to secretin administration
• Imaging studies such as CT or MRI scans to localize the gastrinoma

Treatment

The treatment of ZES involves a combination of medical and surgical approaches. The primary goal is to control the excessive acid production and manage the symptoms.

• Proton pump inhibitors (PPIs) or histamine-2 receptor antagonists (H2RAs) to reduce gastric acid secretion
• Surgical resection of the gastrinoma, if possible
• Chemotherapy or radiation therapy for malignant gastrinomas
• Treatment of complications such as bleeding or perforation of peptic ulcers

Prognosis

The prognosis for patients with ZES depends on the presence and severity of complications, as well as the effectiveness of treatment. With proper management, many patients can experience significant improvement in symptoms and quality of life.