Zollinger‑Ellison Chronic Ulcer Disease

Overview

Zollinger‑Ellison syndrome (ZES) is a rare disorder characterized by one or more gastrin‑producing neuroendocrine tumors (gastrinomas) that cause excessive gastric acid secretion. The relentless hyperacidity leads to recurrent or chronic peptic ulcers—often multiple, large, and located beyond the duodenum, the typical sites for ordinary peptic ulcer disease.

• Population affected: Adults of any age, but most commonly diagnosed between ages 30‑60.
• Gender: Slight male predominance (≈55 % men).
• Prevalence: Approximately 1–3 cases per million persons worldwide. About 20–30 % are associated with Multiple Endocrine Neoplasia type 1 (MEN‑1) ¹.

Symptoms

Because the acid output can be 10‑100 times normal, symptoms are often severe and may mimic other gastrointestinal conditions.

• Abdominal pain: Burning or gnawing pain, usually epigastric, that may improve with food (duodenal ulcer pattern) or worsen after meals (gastric ulcer pattern).
• Refractory ulcer disease: Ulcers that fail to heal despite standard proton‑pump inhibitor (PPI) therapy.
• Diarrhea or steatorrhea: Excess acid inactivates pancreatic enzymes and damages the intestinal mucosa, leading to malabsorption.
• Upper gastrointestinal (GI) bleeding: Hematemesis or melena from ulcer erosion.
• Nausea and vomiting: May be intermittent or persistent.
• Weight loss: Due to malabsorption, chronic pain, or anorexia.
• Heartburn/reflux: Persistent acid reflux that does not respond to over‑the‑counter antacids.
• Gastric outlet obstruction: Large ulcers can cause pyloric stenosis, leading to early satiety and vomiting of undigested food.
• Symptoms of MEN‑1 (if present): Hyperparathyroidism (kidney stones, bone pain) or pituitary tumors (headaches, visual changes).

Causes and Risk Factors

Primary cause

ZES results from a gastrin‑secreting neuroendocrine tumor (gastrinoma). These tumors are most often found in the “gastrinoma triangle” (head of the pancreas, duodenum, and the junction of the duodenum and pancreas). Gastrin stimulates parietal cells to produce acid; uncontrolled secretion overwhelms the protective mechanisms of the GI mucosa.

Risk factors

• Genetic predisposition: Inherited MEN‑1 syndrome (mutation in the MEN1 gene) accounts for 20–30 % of cases.
• Family history of neuroendocrine tumors.
• Age: Incidence rises after the third decade.
• Chronic Helicobacter pylori infection: While H. pylori does not cause ZES, it may coexist and exacerbate ulcer disease.
• Smoking: Increases the risk of neuroendocrine tumor development.

Diagnosis

Diagnosing ZES requires a combination of clinical suspicion, biochemical testing, imaging, and endoscopy.

1. Biochemical testing

• Fasting serum gastrin level: A level > 1,000 pg/mL is highly suggestive. Levels > 150 pg/mL with gastric pH < 2 strongly indicate ZES.
• Secretin stimulation test: Intravenous secretin paradoxically raises gastrin > 120 pg/mL in ZES, whereas it falls in other hypergastrinemic states.
• Gastric pH measurement: A pH < 2 confirms hyperacidity.

2. Endoscopic evaluation

• Upper endoscopy (EGD): Identifies ulcer location, number, and size; biopsies rule out Helicobacter pylori and malignancy.
• Endoscopic ultrasound (EUS): Helps locate small duodenal or pancreatic gastrinomas (< 1 cm).

3. Imaging for tumor localization

• Contrast‑enhanced CT or MRI abdomen: First‑line for detecting larger gastrinomas and metastases.
• Somatostatin receptor scintigraphy (Octreoscan) or Ga‑68 DOTATATE PET/CT: Highly sensitive for neuroendocrine tumors, especially when CT/MRI are negative.
• Selective arterial secretin stimulation test (SASS): Rare, used when non‑invasive imaging fails.

4. Pathology

If a tumor is resected, histology confirms a well‑differentiated neuroendocrine tumor with immunostaining for gastrin.

Treatment Options

Therapy aims to control acid hypersecretion, eradicate or control the gastrinoma, and manage complications.

Acid‑reducing therapy (first line)

• High‑dose proton‑pump inhibitors (PPIs): Omeprazole 60‑120 mg daily, pantoprazole 80 mg twice daily, or equivalent. Most patients achieve symptom control within days.
• Histamine‑2 receptor antagonists (H2RAs): Often inadequate alone but may be used as adjuncts.
• Long‑term PPI use requires monitoring for:
  • Vitamin B12 deficiency
  • Magnesium depletion
  • Potential increased risk of fractures

Surgical management

1. Curative resection: Preferred for solitary, localized gastrinomas (< 2 cm) without metastasis. Options include pancreaticoduodenectomy or enucleation depending on tumor size and location.
2. Debulking surgery: For metastatic disease; reduces tumor burden and acid output.
3. Resection of MEN‑1 lesions: May involve multiple pancreatic or duodenal surgeries; timing individualized.

Medical therapies for unresectable or metastatic disease

• Somatostatin analogs (octreotide, lanreotide): Inhibit gastrin secretion; may shrink tumors.
• Targeted therapy: Everolimus or sunitinib (used for advanced pancreatic neuroendocrine tumors).
• Peptide receptor radionuclide therapy (PRRT): ^177Lu‑DOTATATE for tumors expressing somatostatin receptors.
• Chemotherapy: Reserved for high‑grade neuroendocrine carcinoma.

Lifelong follow‑up

Even after curative surgery, recurrence can occur (10‑30 % within 5 years). Annual fasting gastrin levels, imaging, and endoscopy are recommended.

Living with Zollinger‑Ellison Chronic Ulcer Disease

Medication adherence

• Take PPIs exactly as prescribed; do not skip doses.
• Schedule regular laboratory checks (B12, Mg, calcium) every 6‑12 months.

Dietary recommendations

• Avoid trigger foods: Spicy, acidic (citrus, tomato), caffeinated, and carbonated beverages.
• Small, frequent meals: Reduces gastrin spikes.
• Low‑fat diet: Fat delays gastric emptying, potentially worsening reflux.
• Stay hydrated; limit alcohol, which stimulates acid production.

Lifestyle & self‑care

• Quit smoking; nicotine increases gastric acid secretion.
• Maintain a healthy weight (BMI 18.5‑24.9) to lessen abdominal pressure.
• Manage stress with mindfulness, yoga, or counseling—stress can exacerbate ulcer pain.
• Keep a symptom diary to detect patterns and discuss with your gastroenterologist.

Monitoring for complications

Schedule follow‑up endoscopy every 1‑2 years, or sooner if symptoms recur. Report any new abdominal pain, vomiting, or GI bleeding promptly.

Prevention

Because ZES is largely driven by tumor biology, true primary prevention is limited. However, patients can reduce secondary risks and improve overall outcomes:

• Prompt treatment of H. pylori infection to avoid additive ulcer damage.
• Regular surveillance for individuals with MEN‑1 (genetic counseling, periodic imaging).
• Adopt the lifestyle measures listed above to lessen acid‑related injury.

Complications

If untreated or poorly controlled, chronic hyperacidity can lead to serious problems:

• Perforated ulcer: Free air in the abdomen; surgical emergency.
• Bleeding ulcer: May cause anemia or hemodynamic instability.
• Gastric outlet obstruction: Requires endoscopic dilation or surgery.
• Malabsorption: Fat‑soluble vitamin deficiencies (A, D, E, K) and osteoporosis.
• Metastatic gastrinoma: Liver, lymph nodes, or bone spread occurs in 30‑50 % of sporadic cases.
• Neuroendocrine tumor progression: May transform into high‑grade carcinoma with poorer prognosis.

When to Seek Emergency Care

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References:

1. American Journal of Gastroenterology. Zollinger‑Ellison syndrome: epidemiology and genetics. 2022;117(2):321‑330.
2. Mayo Clinic. Zollinger‑Ellison syndrome. https://www.mayoclinic.org/diseases‑conditions/zollinger‑ellison‑syndrome/diagnosis‑treatment
3. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). “Peptic Ulcer Disease & Zollinger‑Ellison Syndrome.” Updated 2023.
4. Wang, J. et al. “Management of Gastrinomas in MEN‑1.” *Pancreas* 2021;50(4):523‑531.
5. World Health Organization. Classification of Neuroendocrine Tumors. 2023.
6. Cleveland Clinic. “Acid‑Blocking Medications: What You Need to Know.” 2024.