What are duodenal ulcers?
A duodenal ulcer is an open sore in the lining of the duodenum, the first part of the small intestine, that lies immediately distal (after) the stomach. The broad term for ulceration in the stomach or duodenal lining is peptic ulcer disease. Most of the causes of stomach ulcers are also responsible for the development of duodenal ulcers. The duodenum has an inner epithelial lining, known as the mucosa.
It is made up of simple columnar cells and also contains specialized cells that produce mucus and a few digestive enzymes. With duodenal ulcers, the mucosa is eroded revealing the underlying layers like the submucosa and in severe cases, an ulcer may perforate the duodenal wall. Duodenal ulcers are more common than stomach ulcers and are usually a solitary (single) ulcer. The ulcer usually forms close to the pyloric valve and more often occurs on the anterior duodenal wall.
About the Duodenum
The duodenum has its own protective mechanisms against gastric acid in addition to a mucus barrier like the stomach. When acidity is detected in the duodenum, the pancreatic ducts secrete a combination of water and bicarbonate ions to neutralize the gastric acid in the duodenum.
Digestive hormones like secretin are also released into the blood stream to slow down gastric emptying thereby allowing the duodenum to cope with smaller quantities of gastric acid. The epithelial cells can also actively pump out hydrogen ions from the duodenal lumen, further reducing the acid content.
Causes of Duodenal Ulcers
A duodenal ulcer arises when the protective mechanisms that protect the epithelial lining are compromised. The incoming acidic chyme from the stomach can erode the lining of the duodenum. The most common causes of duodenal ulcers, like stomach ulcers, include H.pylori infection and the use of NSAIDs.
Ulcers in the duodenum arise from constant inflammation of the duodenal mucosa eventually leading to the formation of open sores in the lining (ulceration). This is due either to an increase in gastric acid or impairment of the mucus barrier that protects the duodenal lining. In some causative factors of duodenal ulcers, like H.pylori infection, both mechanisms contribute to ulceration.
- Helicobacter pylori (H.pylori) Infection
- H.pylori is a type of bacteria that infects the stomach lining but may also extend to the duodenum especially if the duodenal mucosa is altered in a manner that it resembles the stomach lining (gastric metaplasia).
- H.pylori increases gastric acid secretion in the stomach and also degrades the mucus barrier.
- This allows gastric acid to make contact with the duodenal lining, leading to inflammation and eventually ulceration.
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- NSAIDs are widely available drugs used to reduce inflammation and ease pain.
- These drugs impair the mucus barrier of the duodenum thereby allowing gastric acid to make contact with the duodenal lining.
- Chronic use of NSAIDs are more likely to lead duodenal ulceration.
Other factors may also contribute to ulceration by either significantly increasing gastric acid secretion or compromising the mucus barrier protecting the duodenum. This includes :
- Cigarette smoking
- Alcohol misuse
- Advancing age, especially if there is a history of H.pylori infection
- Severe illness and debilitated patients
- Ingestion of caustic agents
- Hyperacidity conditions like Zollinger-Ellison syndrome
- Epstein-Barr virus (EBV), cytomegalovirus (CMV) or herpes simplex virus-1 (HSV-1)
- Family history
- Chemotherapy and radiation therapy in cancer patients
Signs and Symptoms of Duodenal Ulcers
Inflammation of the duodenum may remain unnoticed for prolonged periods of time with only vague symptoms like changes in appetite and indigestion reported. However, once an ulcer develops, the clinical presentation gradually becomes more defined. It is not uncommon for certain patients to be asymptomatic but this is more often seen in the elderly.
The most common symptom of a duodenal ulcer is epigastric pain. This is the area just below the breastbone and may also be described as upper middle abdominal pain. The nature of the discomfort or pain may vary from a dull ache (stomach ache) that may be dull or gnawing in character to an intense burning pain.
It typically starts an hour or two after eating as the acidic gastric chyme enters the duodenum in larger quantities, and may also occur late at night or early in the morning when gastric acid secretion increases. Patients may awake from sleep and complain of stomach discomfort, indigestion, chest pain and/or abdominal pain.
Many patients report that the pain eases immediately after eating but this is not a feature that is present in every case of duodenal ulcers. Episodes of pain due to duodenal ulcers will most often settle with the use of antacids. Chronic cases with a persistent, often dull ache, are less responsive to antacids although some relief will be reported.
Other symptoms of duodenal ulcers include :
- Regurgitation, rarely vomiting
- Abdominal bloating
- Excessive belching
- Lack of appetite
- Weight loss in severe cases
The symptoms of duodenal ulcers are characteristic of acid reflux and it is not uncommon for a patient complaining of heartburn to be diagnosed with a peptic ulcer. Investigative techniques like an upper GI endoscopy are therefore essential for a conclusive diagnosis.
Treatment of Duodenal Ulcers
Medical treatment for duodenal ulcers involves the use of medication that is also indicated for stomach ulcers and acid reflux. This includes :
- Antacids – neutralizes stomach acid.
- Proton pump inhibitors (PPIs) and H2-blockers – reduces gastric acid production and secretion.
- Sucralfates – coats the duodenal lining and ulcer to prevent further inflammation by gastric acid and allow for the ulcer to heal. Read more on stomach acid medication.
- Antibiotics may be used along with other stomach acid medication in H.pylori infection. Eradication treatment is discussed further under treatment for Helicobacter pylori.
Surgical measures for duodenal ulcers are rare and only considered in patients who are unresponsive to medication. A bleeding ulcer may also require surgical intervention. Surgery is essential in a perforated ulcer.
Diet for Duodenal Ulcers
Dietary factors do not cause duodenal ulcers but may exacerbate the condition. Patients are advised to avoid :
- Spicy foods
- Certain vegetables like onions, garlic, bell peppers and chillies
- Preserved foods
- Caffeinated beverages
- Fatty foods
Dietary guidelines are discussed further under peptic ulcer foods to avoid. Regular small meals are advisable rather than fewer and larger meals.