What is Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)?
Superior mesenteric artery syndrome is an uncommon condition that can block the upper part of the small intestine. It can lead to serious health issues and even death if not diagnosed promptly. Even though it’s a rare condition, it’s important for doctors to keep it in mind when examining someone with symptoms suggesting a blocked intestine, especially if the person has recently lost weight. Non-surgical treatment methods often don’t work well for this syndrome. A surgical procedure called laparoscopic duodenojejunostomy has been found to be a safe and effective treatment option.
What Causes Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)?
Superior Mesenteric Artery (SMA) syndrome is a rare condition where the third part of the duodenum (the first section of the small intestine) gets compressed between the abdominal aorta (the main blood vessel in the abdomen) and the superior mesenteric artery (a major artery supplying blood to the intestines). This syndrome is also known by several other names such as chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome, and cast syndrome.
The syndrome was first described in a medical case report by Carl Von Rokitansky in 1842. But, it was in 1927 that a physician named Wilkie provided more details about the disease, its causes, and how it can be diagnosed.
Risk Factors and Frequency for Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)
Exact numbers of people with SMA syndrome aren’t known, but it’s thought that around 0.1% to 0.3% of people get it. This condition usually affects teenagers and young adults between the age of 10 and 39, but anyone of any age can get it. SMA syndrome is more common in females than males, with about 3 females for every 2 males having the condition. It’s not more common in any particular ethnic group, but there have been cases where it’s run in families.
Signs and Symptoms of Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)
Diagnosing certain medical conditions can be challenging because the signs and symptoms are often unclear and not distinct. People usually show up at the doctor’s office with a mix of symptoms that started either suddenly or gradually. Common symptoms include pain in the upper belly, feeling sick to the stomach (nausea), and throwing up (vomiting). Additional complaints may include a bloated abdomen, unintentional weight loss, feeling full quickly after starting to eat (early satiety), and worsening upper belly pain after meals that gets better when they change positions.
Patients may discover that their symptoms lessen when they adjust their body’s angle. This change can be achieved by laying face down, bringing their knees to the chest, or lying on their left side. The pain can come and go or be constant, and it varies based on how severe the blockage is. If severe enough, the blockage can lead to a dangerous expansion of the stomach.
During the chronic phase, the person may experience recurring post-meal pain, nausea, vomiting, and weight loss. Continuous nausea and vomiting can hamper food consumption, which can lead to further weight loss and make the syndrome worse.
Testing for Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)
SMA syndrome, a condition where your intestine becomes obstructed, typically shows up with unclear symptoms. To figure out if someone has this syndrome, doctors need to look at these symptoms together with certain scans or imaging tests. A bunch of different tests can help with this, including basic x-rays, barium x-rays (which involve a contrast dye), endoscopy, CT scan, Doppler ultrasound, and magnetic resonance angiography (MRA).
Basic x-rays could show a swollen stomach and less gas in the portion of intestine past the stomach. Endoscopy and barium tests can be done, but they don’t always provide clear results, and might not be available quickly in an emergency situation. Endoscopy, though, is often helpful for checking out complications related to SMA syndrome such as slowed down digestion, bile refluxing back into the stomach, inflammation of the stomach, and ulcers in the duodenum, which is the first part of the intestine. This test can also assist in ruling out other causes for duodenal compression.
CT scans have proven to be a valuable tool in diagnosing SMA syndrome. This is because they can measure the angle between the abdominal aorta (the main artery in your abdomen) and the superior mesenteric artery (the artery that supplies blood to your intestines). Some research suggests that certain measurements of this angle can confirm SMA syndrome. This CT scan method has become the standard replacing the MRA for diagnosing this syndrome.
Originally, the normal angle between these two arteries is considered to lie between 38 and 65 degrees, and the distance between the arteries is typically 10 to 28mm. However, in a research study that looked into 8 cases of SMA syndrome, it was reported that an angle smaller than 22 degrees or a distance less than 8mm could be specific and sensitive indicators of the syndrome.
Lab tests aren’t usually of much help in diagnosing SMA syndrome. Even when you’ve lost weight because of the syndrome, you might still have normal levels of electrolytes, proteins, and albumin. Despite being a rare condition, considering SMA syndrome in the list of possible diagnoses is important. A delay in diagnosis could potentially lead to serious health problems including malnutrition, dehydration, electrolyte issues, air fill in the stomach or intestine’s walls, gas in the portal vein (which carries blood from digestive organs to liver), gastrointestinal bleeding, and rupturing of the stomach.
Treatment Options for Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome)
Initial treatment for this condition is non-surgical and tries to manage the issue conservatively. It includes hydration, adjusting imbalances in the body’s electrolytes (minerally charged particles that help your body function), introducing total parenteral nutrition (providing nutrients through a vein instead of eating and drinking) and the use of a nasogastric tube (a thin plastic tube inserted through your nose into your stomach) to relieve pressure in the stomach. The patient is also encouraged to eat small meals and lie on their left side, as this position can help alleviate symptoms.
Nutrition is a significant part of the conservative treatment plan as it can boost the fat around the arteries in the abdomen (mesenteric fat pad), which can indirectly help lessen the symptoms by increasing the angle of the artery (AO angle).
However, many patients might not respond to these conservative measures and end up needing surgery. There are several types of surgery considered for treatment, including procedures like gastrojejunostomy, the Strong procedure (which involves cutting a ligament in the abdomen), transabdominal duodenojejunostomy and laparoscopic duodenojejunostomy.
Traditional open surgery used to be the go-to method until 1998, when the first successful laparoscopic duodenojejunostomy was carried out. This procedure, which uses small incisions and a camera (laparoscope), has since become the most common surgical approach, surpassing the traditional open surgery. A study that reviewed patients who underwent laparoscopic duodenojejunostomy when the conservative treatment failed found that symptoms significantly improved in most of them without major surgery-related complications.
Most surgeons prefer the duodenojejunostomy treatment because of its high success rates and minimized post-surgery complications, such as pain, long hospital stays, and risk of an incisional hernia (where the intestine pushes through the surgical wound).
What else can Superior Mesenteric Artery Syndrome (chronic duodenal ileus, Wilkie syndrome, arterio-mesenteric duodenal compression syndrome and cast syndrome) be?
People may confuse the symptoms of the following conditions:
- Anorexia bulimia
- Anorexia nervosa
- Chronic idiopathic intestinal pseudo-obstruction
- Collagen vascular conditions
- Diabetes mellitus
- Mega duodenum and duodenal ileus
- Peptic ulcer disease
It’s important to get a proper medical evaluation to ensure an accurate diagnosis.
