Summary about Disease
Superior Mesenteric Artery (SMA) Syndrome is a rare digestive condition where the duodenum (the first part of the small intestine) becomes compressed between the superior mesenteric artery (SMA) and the aorta. This compression causes partial or complete blockage of the duodenum, leading to various gastrointestinal symptoms. It's sometimes called Wilkie's Syndrome or cast syndrome.
Symptoms
Common symptoms include:
Nausea and vomiting, often bilious (containing bile)
Abdominal pain, particularly after eating
Feeling of fullness or bloating
Early satiety (feeling full quickly)
Weight loss
Anorexia
Postprandial discomfort (discomfort after eating)
Causes
The primary cause is a decreased angle between the SMA and the aorta. Normally, this angle is between 25 and 60 degrees. In SMA syndrome, the angle decreases to as low as 6 to 15 degrees, pinching the duodenum. This can be due to:
Significant weight loss: Loss of the mesenteric fat pad that cushions the SMA.
Spinal surgery: Especially procedures that involve correcting spinal deformities.
Prolonged bed rest or immobilization: Leading to weakening of abdominal muscles.
Congenital anatomical variations: A naturally narrow SMA angle.
Conditions causing decreased mesenteric fat
Medicine Used
Medication is primarily used for symptom management. Common medications include:
Anti-emetics: To reduce nausea and vomiting (e.g., metoclopramide, ondansetron).
Pain relievers: To manage abdominal pain (analgesics).
Prokinetics: To help with gastric emptying (e.g., metoclopramide).
Nutritional support: To address malnutrition. Total parenteral nutrition (TPN) may be necessary.
Is Communicable
No, Superior Mesenteric Artery Syndrome is not a communicable disease. It is not caused by an infectious agent and cannot be transmitted from person to person.
Precautions
Precautions generally focus on preventing or managing the underlying causes and symptoms:
Maintaining a healthy weight: Especially after weight loss.
Proper posture: To avoid undue pressure on the duodenum.
Frequent, small meals: Easier to digest.
Avoiding prolonged bed rest: Or incorporating regular movement if bed rest is necessary.
Avoiding tight abdominal binders or casts (where applicable).
How long does an outbreak last?
SMA syndrome is not an outbreak-related disease. The duration of symptoms can vary significantly depending on the severity of the compression and the effectiveness of treatment. Some individuals may experience chronic, ongoing symptoms, while others may find relief with conservative management or surgical intervention. There is no outbreak related data.
How is it diagnosed?
Diagnosis typically involves:
Clinical evaluation: Assessing symptoms and medical history.
Imaging studies:
Upper gastrointestinal (GI) series with small bowel follow-through: To visualize the duodenum and identify any obstruction.
CT angiography (CTA): To visualize the SMA and aorta and measure the angle between them.
MRI: Can be used instead of CT to evaluate anatomy.
Duodenal endoscopy: To rule out other causes of duodenal obstruction.
Timeline of Symptoms
The onset and progression of symptoms can vary.
Early stages: Intermittent nausea, vomiting, and abdominal discomfort, especially after eating.
As the condition progresses: Symptoms become more persistent and severe, leading to chronic pain, malnutrition, and significant weight loss.
Important Considerations
Early diagnosis and intervention are crucial to prevent complications such as malnutrition, dehydration, and electrolyte imbalances.
Treatment may involve conservative measures (dietary changes, postural adjustments, medication) or surgical intervention (duodenojejunostomy to bypass the obstruction).
SMA syndrome should be considered in patients with unexplained upper gastrointestinal symptoms, especially if they have a history of significant weight loss, spinal surgery, or other predisposing factors.
A high index of suspicion is needed as SMA syndrome is rare, and symptoms can mimic other gastrointestinal disorders.