Gastric Outlet Obstruction: Symptoms, Types, Causes and Treatment

Gastric outlet obstruction (GOO) is a serious clinical condition that interferes with the normal emptying of the stomach into the duodenum. It can develop suddenly or gradually, causing significant discomfort and impacting quality of life. Whether caused by benign or malignant processes, GOO often presents diagnostic and therapeutic challenges, especially as the causes and best management strategies continue to evolve with advances in medicine. In this article, we’ll explore the key aspects of GOO—including its symptoms, types, underlying causes, and the latest evidence-based treatment options.

Symptoms of Gastric Outlet Obstruction

Gastric outlet obstruction can present with a range of symptoms, often related to the mechanical or functional blockage of the stomach’s exit. Recognizing these symptoms early is crucial for timely diagnosis and effective management.

Symptom	Description	Frequency/Severity	Source(s)
Vomiting	Postprandial, non-bilious, sometimes profuse	Most common, often severe	2 4 8 9
Abdominal Pain	Epigastric, often after eating	Very common	4 8 9
Early Satiety	Feeling full quickly after starting a meal	Common	3 9
Weight Loss	Unintentional, from poor intake/malabsorption	Frequent	1 2 4 8 9
Bloating/Fullness	Sensation of stomach distension	Common	4 9 12
Anorexia	Loss of appetite	Frequent	1 4 8
Dehydration	Due to persistent vomiting	Occasional	2 4 5
Visible Peristalsis	Movement visible on abdominal inspection	Sometimes observed	2 4

Table 1: Key Symptoms

Overview of GOO Symptoms

GOO symptoms are typically a result of either a physical blockage or a disturbance in stomach motility. The stomach's remarkable ability to stretch means that mild or early obstruction may go unnoticed until symptoms become pronounced 9. The nature and severity of symptoms can also hint at the underlying cause and guide further diagnostics.

Vomiting

• Most common sign: Vomiting after eating is a hallmark symptom. It's typically non-bilious (does not contain bile) because the obstruction is proximal to the bile duct entry into the duodenum. Vomiting may be persistent, leading to significant fluid and electrolyte losses 2 4 8 9.
• Timing: Usually, vomiting occurs a few hours after eating as food and gastric secretions accumulate.

Abdominal Pain and Fullness

• Pain: Epigastric discomfort or pain, especially after meals, is common due to gastric distension and irritation 4 8 9.
• Bloating: Patients frequently report abdominal fullness, which may be visible as distension. In advanced cases, visible gastric peristalsis can be seen as the stomach attempts to overcome the obstruction 2 4 12.

Early Satiety and Anorexia

• Early satiety: Patients often feel full after eating only a small amount, reflecting impaired gastric emptying 3 9.
• Anorexia: Loss of appetite is also frequent, contributing to nutritional deficits 1 4 8.

Weight Loss and Dehydration

• Weight loss: Chronic obstruction leads to poor nutritional intake and malabsorption, resulting in unintentional weight loss 1 2 4 8 9.
• Dehydration: Persistent vomiting and poor oral intake can cause significant dehydration and electrolyte imbalances, which can become life-threatening if not addressed 2 4 5.

Additional Features

• Constipation: Reduced intake and dehydration may result in constipation 4.
• Bleeding: Hematemesis (vomiting blood) or melena (black, tarry stools) can occur if the underlying cause is ulceration or malignancy 4.
• Systemic Symptoms: Malaise, pallor (from anemia), and signs of chronic illness may be present, especially in malignancy 4 7.

Types of Gastric Outlet Obstruction

GOO is not a single disease but a clinical syndrome that can result from a variety of pathologies. Classifying GOO helps guide diagnostic and therapeutic decisions.

Type	Description	Typical Patient Profile	Source(s)
Benign	Non-cancerous, often peptic ulcer-related	Younger, history of ulcers	4 6 8 9
Malignant	Cancerous, tumors blocking the outlet	Older, weight loss, anemia	3 4 6 7 8
Functional	Motility disorders, no physical blockage	Variable, often chronic	5 9 12
Congenital	Present from birth, e.g., pyloric stenosis	Infants, children	2

Table 2: Types of GOO

Benign GOO

• Peptic Ulcer Disease: Traditionally, the most common cause was scarring and narrowing from chronic duodenal or gastric ulcers. However, the incidence has decreased due to the widespread use of proton pump inhibitors and H2 blockers 4 6 8.
• Other Causes: Includes caustic injury (from ingestion of corrosive substances), chronic pancreatitis with inflammation or pseudocyst formation, and benign tumors such as large polyps or ectopic pancreas 11 13.

Malignant GOO

• Gastric Cancer: Now the leading cause in many regions, particularly cancers of the distal stomach (antrum) and duodenum 4 6 7 8 9.
• Other Tumors: Pancreatic cancer, neuroendocrine tumors, lymphoma, and metastatic lesions can also cause obstruction by direct invasion or external compression 5 7 9 10.
• Clinical Note: In adults, GOO should always be considered malignant until proven otherwise by appropriate diagnostic investigations 3 6.

Functional/Motility Disorders

• Pseudo-obstruction: Not caused by a mechanical blockage, but rather by abnormal motility, often due to neurohormonal causes or medications. Certain tumors can also cause this by secreting hormones that slow gastric emptying 5 9.
• Diagnosis: Challenging, usually requires exclusion of a physical obstruction with imaging and endoscopy 5 13.

Congenital and Rare Pediatric Types

• Infantile Hypertrophic Pyloric Stenosis: The classic cause in infants—marked by thickening of the pyloric muscle leading to projectile vomiting 2.
• Jodhpur Disease: A rare, idiopathic acquired GOO described in children, typically presenting with vomiting, weight loss, and visible peristalsis without any identifiable obstruction or muscular hypertrophy 2.

Causes of Gastric Outlet Obstruction

The causes of GOO are diverse, ranging from benign inflammation to aggressive cancers. Understanding the underlying cause is essential for choosing the right treatment.

Cause	Mechanism	Prevalence/Context	Source(s)
Peptic Ulcer Disease	Scarring/stricture formation	Declining, still present	4 6 8 9
Gastric Cancer	Tumor growth blocks outlet	Increasing in adults	4 6 7 8
Pancreatic Cancer	External compression/infiltration	Common in malignant GOO	5 7 10
Polyps/Ectopic Pancreas	Large lesions block outlet	Rare, usually benign	11 13
Caustic Injury	Stricture from chemical burns	Often in young adults	4 8
Neuroendocrine Tumors	Mechanical and hormonal effects	Rare, functional GOO	5
Congenital Anomalies	Pyloric stenosis, Jodhpur disease	Infants, children	2

Table 3: Main Causes of GOO

Peptic Ulcer Disease

• Pathology: Chronic inflammation and healing of ulcers can cause fibrosis and narrowing (stricture) of the gastric outlet 4 8 9.
• Trend: Incidence has dropped significantly due to improved medical management of ulcers, but it's still relevant, especially in regions with limited healthcare resources 4 6 7 8.

Malignancy

• Gastric and Antral Carcinomas: Cancers of the distal stomach are now the most common cause of GOO in adults 4 6 7 8.
• Pancreatic and Other Cancers: Tumors in the head of the pancreas, duodenum, and adjacent organs can either invade or compress the gastric outlet 5 7 10.
• Clinical Implication: More than half of adult GOO cases are now due to malignancy, and malignancy should be suspected in any older adult with new-onset symptoms 3 4 6 7.

Benign Non-Ulcer Causes

• Polyps: Large hyperplastic or adenomatous polyps may physically block the gastric outlet 11.
• Ectopic Pancreas: Rare, but when complicated by pseudocyst formation or inflammation, can cause obstruction 13.
• Caustic Injury: Ingestion of corrosive agents can result in scar formation and stricture 4 8.
• Chronic Pancreatitis: Pseudocysts or fibrosis can compress the outlet from outside 8 13.

Neuroendocrine and Functional Tumors

• Neuroendocrine Tumors: These can cause both direct obstruction and functional (pseudo-obstructive) symptoms via hormone secretion that impairs gastric motility 5.
• Functional Causes: Rarely, GOO may be due to severe gastroparesis or motility disorders, sometimes related to systemic diseases or as a paraneoplastic effect 5 9.

Pediatric and Congenital Causes

• Infantile Hypertrophic Pyloric Stenosis: Most common cause in infants; presents with projectile, non-bilious vomiting 2.
• Jodhpur Disease: Idiopathic acquired GOO in children, with no identifiable anatomical cause 2.

Treatment of Gastric Outlet Obstruction

Treatment strategies for GOO depend on the underlying cause, severity of symptoms, and overall patient status. The primary goal is to relieve obstruction, restore oral intake, and address the root cause when possible.

Treatment Modality	Main Indication	Key Features/Outcomes	Source(s)
Endoscopic Stenting	Malignant GOO, palliation	Rapid symptom relief, less invasive, higher re-obstruction rate	9 10 14 15 16 18
Surgical Gastrojejunostomy	Benign/Malignant, good prognosis	Durable, fewer reinterventions, longer recovery	8 10 15 16 18
EUS-Guided Gastroenterostomy	Benign/Malignant, high expertise	High technical/clinical success, promising results	10 14 16 17
Medical Management	Mild/early symptoms, benign	PPIs, fluid/electrolyte correction	4 9
Polypectomy/Lesion Removal	Polyps, ectopic pancreas	Endoscopic or surgical excision	11 13
Pyloroplasty	Selected benign pediatric cases	Restores patency, e.g., Jodhpur disease	2

Table 4: Treatment Options

General Principles

• Stabilization: Initial management includes correction of fluid and electrolyte imbalances, especially potassium and chloride losses due to vomiting 5 9.
• Nutritional Support: In cases of severe obstruction, nasogastric decompression and nutritional support (oral, enteral, or parenteral) may be necessary 1 5.

Endoscopic Stenting

• Indications: Primarily used for palliation in malignant GOO, especially in patients with limited life expectancy or poor surgical candidates 9 10 15 18.
• Advantages: Quick symptom relief, shorter hospital stay, faster return to oral intake 15 18.
• Limitations: Higher rates of stent occlusion, re-obstruction, and need for repeat interventions compared to surgery 15 18.

Surgical Gastrojejunostomy

• Indications: Durable option for both benign and malignant GOO, especially in patients with longer life expectancy and good performance status 8 10 15 18.
• Approach: Bypass procedure connecting the stomach to the jejunum, avoiding the obstructed area.
• Comparison: Fewer reinterventions, longer patency, and better long-term outcomes than stenting, but with longer recovery and higher upfront risks 8 15 18.

EUS-Guided Gastroenterostomy (EUS-GE)

• Technique: Minimally invasive endoscopic creation of a bypass using a lumen-apposing metal stent.
• Evidence: High technical (92-97%) and clinical success rates; lower recurrence and reintervention rates than stenting. Promising for both benign and malignant GOO where expertise exists 10 14 16 17.
• Role in Benign GOO: Can serve as a bridge to definitive surgery or even prevent the need for surgery in many patients 17.

Medical and Supportive Management

• Acute Management: All patients benefit from gastric decompression (NG tube), fluid resuscitation, and correction of metabolic disturbances.
• Pharmacotherapy: Proton pump inhibitors and H2 blockers may be helpful in benign ulcer-related GOO 4 9.
• Prokinetics: Useful in functional or neuroendocrine tumor-related GOO (pseudo-obstruction) 5.

Targeted Treatments

• Polypectomy/Lesion Removal: Large benign polyps or lesions such as ectopic pancreas causing obstruction can be removed endoscopically or surgically 11 13.
• Pyloroplasty: For selected benign cases in children (e.g., Jodhpur disease), surgical widening of the pylorus restores patency 2.

Conclusion

Gastric outlet obstruction is a complex syndrome with diverse causes, clinical presentations, and management strategies. Early recognition and targeted intervention are crucial for optimal outcomes.

Key Takeaways:

• Symptoms: Vomiting, abdominal pain, early satiety, weight loss, and dehydration are hallmark features.
• Types: GOO can be benign, malignant, functional, or congenital—with malignancy now the most common cause in adults.
• Causes: Peptic ulcer disease, gastric and pancreatic cancers, polyps, caustic injury, and rare entities like neuroendocrine tumors or congenital anomalies.
• Treatment: Includes endoscopic stenting (fast relief, more reinterventions), surgical bypass (durable, longer recovery), and innovative techniques like EUS-GE (high success, promising for both benign and malignant cases).
• Individualized Care: The choice of treatment depends on the underlying cause, patient prognosis, and available expertise.

With advances in endoscopic and surgical techniques, the management of GOO has become more nuanced and effective—offering hope for improved patient outcomes even in complex cases.