Gastric outlet obstruction

Signs and symptoms

The primary symptom is vomiting after meals, with vomitus consisting of undigested food and lacking bile. A history of peptic ulcers and weight loss is common. Advanced cases may show wasting, dehydration, visible left-to-right peristalsis, and a succussion splash heard over the stomach. Bowel sounds may be increased (borborygmi), and fullness in the left hypochondrium can occur.

Causes

Causes are divided into benign and malignant categories. Benign causes include peptic ulcer disease, infections such as tuberculosis, infiltrative diseases like amyloidosis, and rare causes like Bouveret syndrome (gallstone blockage).

In children, congenital hypertrophic pyloric stenosis may occur. Pancreatic pseudocyst and pyloric mucosal diaphragm are other benign causes. Malignant causes include gastric adenocarcinoma (including linitis plastica), lymphoma, and gastrointestinal stromal tumors.

Diagnosis

Upper gastrointestinal endoscopy is the most confirmatory investigation. Laboratory findings often show hypochloremic, hypokalemic, and alkalotic states due to loss of hydrogen chloride and potassium; elevated urea and creatinine may indicate dehydration.

Abdominal X-ray may reveal a gastric fluid level. Barium meal and follow-through can show an enlarged stomach and pyloroduodenal stenosis. Gastroscopy aids in determining the cause and can be used therapeutically.

Treatment

Treatment depends on the cause and is usually surgical or medical. For peptic ulcer disease, conservative management with nasogastric suction, fluid and electrolyte replacement, and proton pump inhibitors often resolves edema. Surgery, such as antrectomy, vagotomy, Billroth I, or bilateral truncal vagotomy with gastrojejunostomy, is indicated for significant obstruction or failed medical therapy. Endoscopic balloon dilation can be an alternative, with success rates of 76% after repeat dilatations.

Did You Know?

• In a peptic ulcer, obstruction is believed to result from edema and scarring, followed by healing and fibrosis at the gastroduodenal junction.
• Causation related to ulcers may involve severe pain that the patient may interpret as a heart condition or attack.
• The differential diagnosis includes early gastric carcinoma, hiatal hernia, gastroesophageal reflux, adrenal insufficiency, and inborn errors of metabolism.