Sphincter of Oddi Dysfunction
Bile is a digestive juice that your liver makes. Your gallbladder stores it. Then it flows into the upper part of your small intestine to help you digest food. At the same time, your pancreas makes juices that are important for digestion. Both bile and your pancreatic juices flow to your small intestine through a common duct that is opened and closed by a round valve. The valve is a muscle called the sphincter of Oddi.
In rare cases, the sphincter of Oddi goes into spasm. It clamps shut and cannot relax. Other times it may be narrowed from previous inflammation. This is called sphincter of Oddi dysfunction (SOD). The condition causes intense belly pain. Your digestive juices back up into your pancreas and into the bile ducts of your liver. Another type of SOD happens when the sphincter of Oddi becomes stiff and narrow. This prevents digestive juices from entering your small intestine.
Healthcare providers aren't sure why SOD happens. But you're most at risk for this condition if you've had your gallbladder removed. If you have had gastric bypass weight-loss surgery, you may also develop it.
The main symptom of SOD is severe stomach pain that comes and goes. The symptoms can feel similar to a gallbladder attack. You may have pain in your upper belly that seems to move, or spread, into your right shoulder. You may also have chest pain that feels like a heart attack. Sometimes it causes pancreatitis. Pancreatitis is a severe swelling and irritation of the pancreas, and symptoms include stomach pain around the belly button, and pain in the left side under the ribs. Symptoms that go along with the belly pain include:
Loss of appetite
Each year, about half a million people in the U.S. have their gallbladder removed. This increases their risk for SOD. Although up to 20% of patients have pain symptoms after gallbladder surgery, Sphincter of Oddi dysfunction is considered rare. Risk factors for SOD may be similar to those for gallbladder disease. They include:
Your healthcare provider may suspect SOD if you have recurrent pancreatitis or bouts of stomach pain after your gallbladder was taken out. Treatment for SOD does not help stomach pain not caused by SOD, so it is very important to do testing to identify patients who truly have the disease and will benefit from treatment. These tests may include:
Blood tests for higher-than-normal liver or pancreatic enzymes
Ultrasound of the bile duct, liver, or pancreas
MRCP, or magnetic resonance cholangio-pancreatography. This is an imaging study of the bile and pancreatic ducts
ERCP, endoscopic retrograde cholangio-pancreatography. This is a procedure that looks directly inside the duct system while getting X-ray images, taking visual pictures, and measuring pressure
However, sphincter of Oddi dysfunction is now considered less common than before. Many people who were initially diagnosed have been found to have other conditions.
Your healthcare provider may also test you for SOD if you are feeling severe belly pain after recovery from a gastric bypass surgery.
Treatment of SOD depends on the type you have. It's also affected by how bad your symptoms are. If diagnostic tests show that your symptoms stem from a backup of digestive juices into your liver or pancreas and you are having symptoms often, you may have your sphincter of Oddi muscle cut surgically during an ERCP exam. This procedure is called sphincterotomy. It’s generally effective and relieves symptoms of SOD about 70% of the time.
Most complications of SOD are seen in people who need to have their bile duct system examined. Up to 10% of people develop pancreatitis after the medical procedure ERCP. This happens with or without surgery to cut the sphincter. There are certain situations where this is more likely to happen and you can discuss this with your provider. A rectal medicine is often used to decrease the risk of pancreatitis. This complication usually clears up within a few days of hospital treatment. For a few people it may result in weeks or months of hospitalization.
Complications from surgically cutting the sphincter of Oddi may include bleeding, infection, and delayed narrowing of the duct system because of scarring.
When to call the healthcare provider
Let your healthcare provider know about severe stomach pain that is not going away or keeps coming back. Also, let your healthcare provider know if you have these symptoms, especially after gallbladder surgery:
Loss of appetite
Living with SOD
If you have an SOD diagnosis or you are recovering from sphincterotomy, follow all your healthcare provider's orders. Take all your medicines as directed, and make sure your healthcare provider knows about any other medicines you take, including over-the-counter medicines, supplements, or herbs.
Tips for living with SOD include: