Superior mesenteric artery syndrome

Background

• AKA: Wilke's syndrome
• Rare condition, first described by Von Rokitansky in 1861 and then further studied in detail by Wilke in 1912
• Occurs when duodenum is compressed between aorta and superior mesenteric artery
• Can lead to gastrointestinal obstruction at level of duodenum
  • Chronic, intermittent, or acute
  • Partial or complete
• Controversy over this diagnosis

Etiology

• SMA takes off from the abdominal aorta at about 45 degree angle, due to cushioning from fatty/lymphatic tissue called mesenteric pad
• Third part of the duodenum courses between the angle formed
• Narrowing of this angle can cause entrap and compress of the duodenum
• Factors that narrow this angle include:
  • Significant weight loss (most common cause)
• Corrective spinal surgery for scoliosis lengthens the spine
  • Congenital defects, suggested genetic predisposition
  • Abdominal adhesions

Clinical Features

• Early satiety, belching, post-prandial bloating, weight loss
• Nausea and vomiting, can be bilious
• Abdominal pain, mid-abdomen, may be improved with changes of position
• Proximal small bowel obstruction

Differential Diagnosis

• See Abdominal Pain
• See Nausea and vomiting

Evaluation

• Evaluate for alternative causes of symptoms and for complications
• Suspected based on signs and symptoms
• Diagnosis confirmed by imaging:
  • Upper GI series
  • Upper endoscopy
  • CT

Management

• Correct dehydration, electrolyte abnormalities, malnutrition
• Primary goal is to correct the underlying cause, typically regain lost weight
• Acute management:
  • Adjusting body position to alleviate symptoms, such as knee to chest or lying on left side
  • Nasogastric tube for decompression
• Some patients may require a feeding tube distal to the obstruction or parenteral nutrition
• Surgery sometimes indicated
  • Strong's procedure: duodenum moved to the right of the SMA
  • Gastrojejunostomy, duodenojejunostomy

Disposition

• Depends on clinical presentation
• If complete obstruction, admission for decompression and nutrition
• Outcome excellent with early diagnosis and appropriate treatment

See Also

• Acute gastric dilation

References

• 1. <Karrer FM. Superior Mesenteric Artery Syndrome. Medscape Reference. Jan 2017; http://emedicine.medscape.com/article/932220-overview.>
• 2. <Pleoa A, Constantinescu C, Crumpei F, and Cotea E. Superior mesenteric artery syndrome: an unusual cause of intestinal obstruction. "J Gastrointest Liver Dis". Mar 2006; 15(1): 69-72.>
• 3. <Lorentziadis M. Wilke's syndrome. A rare cause of duodenal obstruction. "Ann Gastroenterol." 2011; 24(1): 59-61.