What causes pyloric stenosis in adults

Overview

Pyloric stenosis refers to a condition where the pylorus, the muscular valve at the lower part of the stomach that opens into the duodenum (the first part of the small intestine), becomes abnormally narrowed. While commonly recognized in infants, it can also occur in adults. Adult pyloric stenosis is generally acquired rather than congenital, meaning it develops later in life due to various underlying conditions.

Causes of Pyloric Stenosis in Adults

Peptic Ulcer Disease

The most prevalent cause of pyloric stenosis in adults is chronic or recurrent peptic ulcer disease. Peptic ulcers are sores that develop on the lining of the stomach or the upper part of the small intestine (duodenum). When these ulcers, particularly those located near the pylorus, heal, they can leave behind scar tissue. Over time, repeated ulceration and healing cycles lead to progressive scarring and fibrosis, which stiffens and narrows the pyloric channel. This narrowing impedes the normal passage of stomach contents into the duodenum, leading to symptoms of gastric outlet obstruction.

Inflammatory Conditions

Certain chronic inflammatory conditions can also contribute to pyloric stenosis. For instance, Crohn's disease, an inflammatory bowel disease that can affect any part of the gastrointestinal tract, can cause inflammation and subsequent thickening and narrowing of the pylorus or duodenum. Other inflammatory processes, though less common, might also play a role.

Malignancy

Cancer of the stomach (gastric adenocarcinoma) or the duodenum can also cause obstruction at the pylorus. Tumors can grow to obstruct the lumen directly, or they can cause inflammation and swelling that leads to stenosis. This is a more serious cause and requires prompt diagnosis and treatment.

Previous Surgery

Individuals who have undergone previous surgery involving the stomach or pyloric region may develop stenosis as a complication. Surgeries like gastric resection (e.g., for ulcers or cancer), pyloroplasty (a procedure to widen the pylorus), or other abdominal surgeries can sometimes lead to scarring or adhesions that constrict the pyloric channel.

Other Rare Causes

Less common causes include congenital anomalies that become symptomatic in adulthood, certain medications, external compression from adjacent masses, and rare granulomatous diseases.

Symptoms

The symptoms of adult pyloric stenosis are primarily related to the inability of the stomach to empty its contents effectively. These often develop gradually and can include:

• Nausea and vomiting, often projectile and containing undigested food
• A feeling of fullness after eating very little (early satiety)
• Abdominal pain or discomfort, typically in the upper abdomen
• Unintentional weight loss
• Bloating
• Loss of appetite

Diagnosis

Diagnosing pyloric stenosis in adults typically involves a combination of medical history, physical examination, and diagnostic tests:

• Upper Endoscopy (EGD): This is often the primary diagnostic tool. A flexible tube with a camera is inserted down the throat to visualize the esophagus, stomach, and duodenum. It allows direct inspection of the pylorus, assessment of the degree of narrowing, and biopsy of any suspicious tissue to rule out malignancy.
• Imaging Studies: Barium studies (upper GI series) can show delayed emptying and the narrowed pyloric channel. CT scans or MRI can provide detailed cross-sectional views of the stomach, duodenum, and surrounding structures, helping to identify the cause of obstruction (e.g., tumor, inflammation, scarring).
• Gastric Emptying Scintigraphy: This test measures how quickly food leaves the stomach.

Treatment

Treatment depends on the underlying cause and the severity of the stenosis. Options may include:

• Dietary Modifications: A soft, low-fiber diet may help ease symptoms in mild cases.
• Medications: Proton pump inhibitors (PPIs) may be prescribed to reduce stomach acid and promote healing of ulcers, potentially alleviating inflammation.
• Endoscopic Balloon Dilation: In some cases, an endoscope can be used to pass a balloon through the narrowed pylorus and inflate it to stretch the channel.
• Surgery: For severe or persistent cases, or when malignancy is suspected, surgery may be necessary. This often involves a pyloroplasty (widening the pylorus) or a partial gastrectomy (removal of part of the stomach).

If you are experiencing symptoms suggestive of pyloric stenosis, it is crucial to consult a healthcare professional for accurate diagnosis and appropriate management.