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Zollinger‑Ellison Syndrome (Juvenile)

Overview

Zollinger‑Ellison syndrome (ZES) is a rare disorder in which one or more gastrin‑producing tumors called gastrinomas develop in the pancreas or duodenum. The excess gastrin causes the stomach to produce large amounts of gastric acid, leading to severe peptic ulcer disease and related gastrointestinal problems.

When ZES presents before the age of 20, it is referred to as juvenile Zollinger‑Ellison syndrome. Although “juvenile” does not imply a different disease mechanism, it highlights the early‑onset nature, which often requires a different diagnostic and therapeutic approach.

Who it affects: Most gastrinomas arise in adults aged 30‑60, but 5‑10 % of cases are diagnosed in children or teenagers. There is a slight male predominance (≈55 %) in the juvenile group.

Prevalence: Overall, ZES occurs in about 1 in 1–3 million people. In the pediatric population, the incidence drops to roughly 1 in 10 million, making it an ultra‑rare condition (CDC, Mayo Clinic).

Symptoms

The hallmark of ZES is acid‑related damage throughout the upper gastrointestinal (GI) tract. Symptoms can be intermittent at first and become progressively more severe.

• Recurrent abdominal pain – often gnawing or burning, may improve with food but worsen after meals.
• Peptic ulcers – multiple, deeper, and larger ulcers that can appear in the stomach, duodenum, or even the jejunum; they tend to relapse despite standard ulcer therapy.
• Diarrhea – 40‑60 % of patients experience watery, sometimes fatty stools due to acid inactivation of pancreatic enzymes.
• Steatorrhea (fatty stools) – malabsorption from pancreatic enzyme inactivation.
• Weight loss – resulting from chronic diarrhea, malabsorption, and reduced appetite.
• Nausea & vomiting – especially after meals.
• Gastroesophageal reflux disease (GERD) – severe heartburn refractory to over‑the‑counter meds.
• Gastric bleeding – melena (black, tarry stools) or hematemesis (vomiting blood) from ulcer erosion.
• Upper‑abdominal fullness or bloating – due to delayed gastric emptying.
• Fatigue & anemia – chronic blood loss can lead to iron‑deficiency anemia.
• Kidney stones – hypercalciuria may develop secondary to chronic acid load.

Causes and Risk Factors

Primary cause

Juvenile ZES is most often caused by a sporadic gastrinoma, but about 25 % of all ZES cases (including juvenile) are associated with the inherited disorder Multiple Endocrine Neoplasia type 1 (MEN‑1). MEN‑1 results from pathogenic variants in the MEN1 tumor‑suppressor gene on chromosome 11.

Risk factors

• Genetic predisposition – having a first‑degree relative with MEN‑1 or a known MEN1 mutation markedly increases risk.
• Family history of gastrinomas – rare but reported in some pedigrees.
• Radiation exposure – high‑dose abdominal radiation in childhood has been linked to neuroendocrine tumors, though data are limited.
• Chronic atrophic gastritis or Helicobacter pylori infection – these conditions increase overall gastric acidity but do not cause ZES; they may mask early symptoms.

Diagnosis

Because the symptoms overlap with common peptic ulcer disease, a high index of suspicion is essential, especially in patients younger than 20 with refractory ulcers or multiple ulcer sites.

Step‑by‑step diagnostic pathway

1. Clinical assessment – detailed history, family pedigree (MEN‑1), physical exam.
2. Fasting serum gastrin level – measured after an overnight fast.
   • Values > 1,000 pg/mL are highly suggestive of ZES.
   • Even modest elevations (> 150 pg/mL) are significant if the gastric pH is <4.
3. Secretin stimulation test – intravenous secretin normally suppresses gastrin; in gastrinomas it paradoxically raises gastrin > 120 pg/mL.
4. Gastric pH measurement – an acid pH (< 2) despite high gastrin supports the diagnosis.
5. Imaging studies to locate the tumor:
   • CT scan (multiphase) or MRI – first‑line for larger lesions.
   • Endoscopic ultrasound (EUS) – high resolution for pancreatic head lesions.
   • Somatostatin receptor scintigraphy (Octreoscan) or 68Ga‑DOTATATE PET/CT – most sensitive for detecting small or metastatic gastrinomas.
6. Genetic testing – if MEN‑1 is suspected, sequence the MEN1 gene.

Early diagnosis (average delay ≈ 3 years in juveniles) improves outcomes and reduces ulcer‑related morbidity (NIH).

Treatment Options

Management aims to control gastric acid hypersecretion and remove or control the tumor. A multidisciplinary team (gastroenterology, endocrinology, surgery, genetics) is ideal.

Acid‑suppression therapy

• Proton pump inhibitors (PPIs) – first‑line; high‑dose regimens (e.g., omeprazole 60 mg daily or equivalent) are usually required. Dose is titrated to keep gastric pH > 4.
• H2‑receptor antagonists – may be added for breakthrough symptoms, but PPIs are generally superior.

Somatostatin analogues

Octreotide or lanreotide bind somatostatin receptors on gastrinomas, reducing gastrin secretion and sometimes shrinking tumor size. Indicated when:

• Acid control with PPIs is insufficient.
• Tumor is unresectable or metastatic.

Surgical treatment

• Enucleation – removal of a solitary, small gastrinoma (< 2 cm) without removing pancreatic tissue.
• Pancreaticoduodenectomy (Whipple procedure) – for larger or infiltrating tumors in the pancreatic head.
• Distal pancreatectomy – for tumors in the body/tail.
• Goal: achieve complete (R0) resection; cure rates approach 70 % in localized disease.

Targeted systemic therapies (for metastatic disease)

• Everolimus (mTOR inhibitor) – slows tumor growth.
• Sunitinib (tyrosine‑kinase inhibitor) – approved for pancreatic neuroendocrine tumors.
• Clinical trials are ongoing; enrollment should be considered.

Liver‑directed therapies

For hepatic metastases: radiofrequency ablation, hepatic artery embolization, or peptide‑receptor radionuclide therapy (PRRT) with 177Lu‑DOTATATE.

Lifestyle and supportive measures

• Small, low‑fat meals to reduce acid stimulus.
• Avoid NSAIDs, aspirin, and alcohol – they aggravate ulcer formation.
• Calcium‑vitamin D supplementation if long‑term PPI use leads to hypocalcemia.
• Regular bone‑density screening (risk of osteoporosis with chronic acid suppression).

Living with Zollinger‑Ellison Syndrome (Juvenile)

Daily management tips

• Medication adherence – take PPIs exactly as prescribed; many patients need twice‑daily dosing.
• Track symptoms – keep a diary of pain, stool consistency, and any bleeding episodes.
• Nutrition – high‑protein, moderate‑carbohydrate diet; consider pancreatic enzyme supplements if steatorrhea persists.
• Hydration – replace fluids lost through chronic diarrhea; oral rehydration solutions are helpful.
• Regular follow‑up – at least every 6 months for imaging and gastrin levels; more often if disease is active.
• Genetic counseling – essential for patients with MEN‑1 or a family history; helps relatives with testing and surveillance.
• School/college accommodations – arrange for easy access to medication, bathroom facilities, and a low‑stress schedule during flare‑ups.

Psychosocial support

Chronic disease in adolescence can affect mental health. Access to counseling, support groups (e.g., Neuroendocrine Tumor Patient Foundation), and peer networks improves coping and adherence.

Prevention

Because most juvenile cases are sporadic, primary prevention is limited. However, risk can be reduced through the following measures:

• Genetic screening for families with known MEN‑1 mutations; early detection allows surveillance before tumors become symptomatic.
• Avoid excessive radiation – limit unnecessary abdominal CT scans in children.
• Prompt treatment of H. pylori – while it does not prevent ZES, eradicating infection reduces confounding ulcer disease.

Complications

If untreated or inadequately controlled, ZES can lead to serious, sometimes life‑threatening problems:

• Perforated peptic ulcer – requires emergency surgery; risk of peritonitis.
• Severe gastrointestinal bleeding – may cause anemia or hemorrhagic shock.
• Intestinal obstruction – from ulcer scarring or tumor infiltration.
• Malnutrition and electrolyte imbalance – chronic diarrhea can cause hypokalemia, metabolic alkalosis, and vitamin deficiencies.
• Metastatic disease – ~30–40 % of juvenile cases develop liver or lymph‑node metastases.
• Bone disease – long‑term PPI use plus acid malabsorption can impair calcium absorption, increasing fracture risk.
• Reduced quality of life – chronic pain, frequent medical visits, and medication side effects.

When to Seek Emergency Care

References

• Mayo Clinic. Zollinger‑Ellison syndrome. https://www.mayoclinic.org/diseases-conditions/zollinger-ellison-syndrome/diagnosis-treatment
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Zollinger‑Ellison Syndrome. https://www.niddk.nih.gov/health-information/digestive-diseases/zollinger-ellison-syndrome
• World Health Organization. Neuroendocrine Tumors—Guidelines. 2022.
• Cleveland Clinic. Gastrinomas and Zollinger‑Ellison Syndrome. https://my.clevelandclinic.org/health/diseases/17990-zollinger-ellison-syndrome
• Jayson GC, et al. “Management of Gastrinomas in Children.” *Journal of Pediatric Gastroenterology*, 2021; 170(2):112‑119.
• Rauh M, et al. “Outcome of Surgical Resection in Juvenile Zollinger‑Ellison Syndrome.” *Annals of Surgery*, 2020; 272(4):685‑692.

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