Peptic ulcer disease (PUD) is the term for open sores in the lining of the stomach and first part of the small intestine known as the duodenum. It is mainly due to the action of the highly corrosive stomach acid and enzymes and occurs as a result of disturbances caused by primarily by two causative factors – H.pylori bacteria and the use of NSAIDs (non-steroidal anti-inflammatory drugs). Ongoing irritation and inflammation of stomach and duodenum may extend deep into the wall and thereby cause erosion of the lining. This is seen as an open sore or ulcer. When it occurs in the stomach it is referred to as a stomach ulcer and if it occurs in the duodenum of the small intestine then it is known as a duodenal ulcer. Collectively these ulcers are referred to as peptic ulcers.
Acid Protection of the Stomach and Duodenum
The entire alimentary tract is lined by epithelium that is similar to the epithelial linings of other hollow cavities in the body, but has adapted specifically for the environment within the gut. The most resilient of these epithelial linings is that of the stomach. It is capable of regenerating as fast as within 2 to 3 days and has specialized mechanisms that allow it to hold the highly corrosive stomach acid.
As explained under gastric acid secretion, the stomach wall is able to produce and secrete highly concentrated hydrochloric acid (HCl) and strong protein-digesting enzymes yet it is able to withstand the effects. This is mainly facilitated by a mucus barrier that separates the lining of the stomach from the acid and enzymes within it. After partially digesting and liquefying food, the acid and enzymes also enter the duodenum of the small intestine.
This part of the alimentary tract also has mechanisms to deal with these highly corrosive chemicals. Water and bicarbonate ions from the pancreas quickly enter the duodenum to neutralize and dilute the acid and enzymes. The lining of the duodenum also secretes mucus, although not to the degree of the stomach, to temporarily protect it against the acid and enzymes coming through from the stomach.
Erosion of the Lining
When the protective mechanisms are compromised, the lining of the stomach and duodenum are exposed to the corrosive effects of the acid and enzymes. The two most common causes of these disturbances are Helicobacter pylori (H.pylori) infection and the long term use of NSAIDs. Both factors may increase the stomach acid production, alter its pH to render it more acidic and compromise the mucus barrier. These factors may also directly irritate the epithelial lining but the inflammation is mainly due to exposure to the acidic gastric juices.
Initially the inner wall experiences inflammation which is limited to the superficial layers – mucosa and submucosa. However, recurrent or persistent inflammation and prolonged exposure to the stomach acid consumes the outer layers thereby exposing the inner tissue. These open sores are the ulcers that are known as stomach or duodenal ulcers depending on its location. For more information, refer to what is a peptic ulcer and what causes peptic ulcers?
Peptic Ulcer Pain
There are several symptoms of peptic ulcer disease, however, the most prominent is the upper abdominal pain. It is often accompanied by nausea, vomiting, changes in appetite and sometime even weight loss. When there is significant bleeding from the ulcers, then there may be blood in the vomitus (appears like dark ‘coffee grounds’) and possibly even the stool (appears black and tarry). However, none of these symptoms are specific for peptic ulcer disease. Noting the location, character, duration and modalities of the pain may assist in confirming that it is due to peptic ulcers.
The pain is typically located in the epigastrium. This is the upper middle portion of the abdomen just below the sternum (breastbone). The pain, however, may also be slightly more to the left, either under the ribcage or immediately below it. It tend to radiate to the back, although the pain may be felt in the lower part of chest or extend to the umbilicus.
Peptic ulcer pain is mild to moderate most of the time unlike the severe pain seen with gallstones and acute pancreatitis that also cause epigastric pain. It usually described as a gnawing pain that develops gradually in comparison to the sudden onset of pain in acute pancreatitis and the progressively worsening pain of gallstones.
Peptic ulcer pain tends to last for less than 2 hours and sometimes as short as just 30 minutes before resolving spontaneously. The pain tends to arise when hungry and is more often experienced at night. However, it can resolve for weeks or sometimes even months before returning.
Peptic ulcer pain is triggered and exacerbated by spicy foods, alcohol and certain medication like NSAIDs. The pain may also aggravate during periods of stress. Food helps to relieve the pain as well as antacids. Many patients with peptic ulcer disease also report pain relief after vomiting.