Sphincter of Oddi Dysfunction
Bile is a digestive juice that your liver produces. 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. 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.
Health care 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 abdominal pain that comes and goes. All 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. Symptoms that go along with the belly pain include:
Loss of appetite
Who's at risk
Each year, about half a million people in the U.S. have their gallbladder removed. Up to 20% of people may have some symptoms of SOD afterward. Risk factors for SOD are similar to those for gallbladder disease. They include:
Your health care provider may suspect SOD if you have bouts of abdominal pain after your gallbladder was taken out. Of the 10% to 20% of people who have belly pain after this procedure, about half will have testing that suggests SOD. 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
Your health care 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.
If you have type III SOD, you have symptoms of SOD, but your diagnostic tests do not show actual evidence of blockage or backup of digestive juices. Treatment for type III SOD starts with medications like pain relievers, muscle relaxants, and occasionally antidepressants. Sphincterotomy is done only if medications don’t help.
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. Pancreatitis is a severe swelling and irritation of the pancreas. 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 health care provider
Let your health care provider know about severe abdominal pain that is not going away or keeps coming back. Also, let your health care 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 health care provider's orders. Take all your medications as directed, and make sure your health care provider knows about any other medications you take, including over-the-counter medicines, supplements, or herbs.
Tips for living with SOD include: