Laparoscopic gastrojejunostomy for superior mesenteric artery syndrome in a patient with Parkinson’s disease

Background

Superior mesenteric artery (SMA) syndrome is an uncommon cause of high intestinal obstruction characterised by compression of the third portion of the duodenum between the abdominal aorta and the SMA. The condition was first described by Rokitansky in 1861 but it was Wilkie who published the first large case series in 1927. ¹ By the 1980s, there were approximately 400 accounts of SMA syndrome ² in medical literature but at the time of writing, no reports of patients with Parkinson’s disease (PD) linked with a diagnosis of SMA syndrome.

Although rare and difficult to diagnose, early recognition of SMA syndrome allows prompt treatment to reduce the associated high mortality rate of intestinal ischaemia. In this case report, we discuss an unusual case of SMA syndrome which failed to improve with medical management but was treated successfully with laparoscopic gastrojejunostomy and Roux-en-Y anastomosis.

Case presentation

A 78-year-old Caucasian female patient presented to our university teaching hospital with worsening upper abdominal pain and profuse vomiting for several days. Interestingly, the patient described being frightened to eat as the pain was significantly worse during mealtimes. Of note she had advanced PD and was experiencing frequent freezing episodes despite no recent changes to her regular medication. Other past medical history included hypertension and cholelithiasis which was demonstrated by ultrasonography on a previous hospital admission. She was a non-smoker and did not drink alcohol.

On clinical examination, the patient was afebrile with normal observations. Palpation of the abdomen revealed tenderness and distension in the upper region without peritonism. In addition, she was noted to have a low body mass index (BMI) of 19 kg/m². Blood tests showed a raised C-reactive protein of 141 mg/L whilst the remainder were within normal limits. The provisional diagnosis was biliary colic.

The abdominal radiograph displayed a gas-filled stomach only (Figure 1). As the patient’s vomiting persisted despite regular anti-emetic medication, proximal bowel obstruction was now suspected and a nasogastric (NG) tube was inserted to good effect, draining a large quantity of fluid. OPEN IN VIEWER

Upper gastrointestinal endoscopy demonstrated extrinsic duodenal compression causing dilatation of the proximal duodenum and stomach. Urgent computed tomography scan showed an abrupt calibre change as the duodenum passed anterior to the spine at D3 (Figure 2), confirming proximal intestinal obstruction. On the basis of the patient’s symptoms and investigative results, the diagnosis was revised and felt most likely due to SMA syndrome. OPEN IN VIEWER

In view of the patient’s high risk for surgical intervention, the decision was made to continue conservative treatment. The patient was advised to assume the left lateral decubitus position and a peripherally inserted central catheter was placed to administer total parenteral nutrition. However, repeated difficulties with intravenous line placement and falling serum albumin levels indicated that non-operative treatment was ineffective and now the patient’s condition necessitated surgical intervention.

At laparoscopy, the stomach and proximal duodenum was evidently dilated up to the level of D3 with collapsed small intestine beyond this. Laparoscopic gastrojejunostomy and Roux-en-Y anastomosis was performed to bypass the obstruction. At 55 cm from the duodenojejunal flexure, the Roux loop was fashioned and anastomosed to the biliary limb. The mesenteric defect was closed with non-absorbable suture. On the first post-operative day, the patient was commenced on oral fluid intake and pureed food by the second day. On the seventh day, the patient’s condition was deemed suitable for discharge. Outpatient clinic review at three months confirmed she had made a full recovery and improved her nutritional status, increasing her BMI from 19 kg/m² to 22.5 kg/m². The patient required no further surgical input and was subsequently discharged from follow-up.

Discussion

SMA syndrome is an uncommon cause of intestinal obstruction in which the third portion of the duodenum is compressed by the SMA and the aorta. ³ In the angle between the origin of the SMA and the aorta, a cushion of intra-abdominal adipose tissue surrounds the duodenum. ⁴ When this mesenteric cushion is reduced and thereby narrowing the aortomesenteric angle, the duodenum is susceptible to compression by the SMA. BMI has been shown to have a direct correlation with the aortomesenteric angle, as the BMI decreases so does the angle. ⁵

Identified predisposing factors include an acute aortomesenteric angle, a low origin point of SMA or an abnormally high fixation of the duodenum to the ligament of Treitz. ³ SMA syndrome has been commonly associated with conditions causing extreme weight loss such as hypercatabolic states and anorexia nervosa, ⁶ or following corrective spinal surgery whereby the SMA is forcibly hyper-extended across the duodenum.^6,7

The classical presenting symptoms include post-prandial abdominal pain and distension, vomiting and even in some cases a fear of food (sitophobia). Females are more likely to be affected and the majority of patients are underweight or malnourished at the time of diagnosis.^3,7

The gold standard for investigating SMA syndrome is upper gastrointestinal series or computed tomography imaging;^3,4 however, the clinical diagnosis is frequently made by process of exclusion. Upper gastrointestinal barium studies showed the prevalence of SMA syndrome is low at less than 0.4%. ² Primary treatment involves conservative measures with the patient adopting left lateral decubitus position and NG tube placement to reduce stomach contents and dilatation. Electrolyte abnormalities should be addressed and nutritional support by enteral or parenteral methods may be considered. ⁴ For cases not amenable to conservative treatment, surgical intervention is required. Surgical options can vary between dividing the ligament of Treitz for mobilising the duodenum, to procedures to bypass the compression such as duodenojejunostomy or gastrojejunostomy. There are accounts of SMA syndrome successfully treated by laparoscopic approach but more commonly by duodenojejunostomy. ⁴

In this case, bypass by gastrojejunostomy was selected to allow adequate decompression of the upper gastrointestinal tract following failed conservative treatment. The decision to perform gastrojejunostomy rather than duodenojejunostomy was made after consideration of several points. The operating surgeon, experienced in upper gastrointestinal and bariatric surgery, wanted to avoid a potentially higher risk of anastomotic leak if operating on a distended duodenum close to the area of compression. The stomach being more proximal anatomically and now decompressed following NG tube aspiration was therefore chosen for anastomosis with jejunum. The patient was expected to recover well from surgery and improved nutrition would serve to replenish the mesenteric cushion to increase the aortomesenteric angle, thus further relieving duodenal compression.

Figure 3 illustrates the trocar placements in this case. A 12-mm sub-umbilical port was inserted by open Hasson technique for endoscope placement. Further ports were inserted under vision to the right and left abdomen. The 12-mm right lateral port allowed access for a laparoscopic linear stapler for the anastomoses. The 11-mm left lateral port provided the use of a grasper and further access by linear stapler if needed. No surgical drains were required. OPEN IN VIEWER

The particular implication for this patient was her background history of advanced PD. Loss of weight is commonly observed as a consequence of PD with a notable higher proportion in females. ⁸ Weight loss is often due to a combination of dysphagia, cognitive impairment and increased energy expenditure from dyskinesias. ⁹

The pharmacokinetics of dopaminergic drugs rely upon normal gastric emptying and absorption from the proximal small bowel. ¹⁰ The mechanisms of SMA syndrome can cause delayed gastric emptying and proximal gastrointestinal tract dilatation. This in turn could lead to inadequate drug uptake and may explain the freezing episodes experienced by the patient. Without surgery, the patient’s worsening Parkinsonian symptoms and malnutrition would have accelerated her clinical deterioration.

Conclusions

Our case report highlights the importance for awareness of pre-morbid conditions such as PD which have unique metabolic demands that may contribute to patients’ medical presentations. To arrive at the final diagnosis of SMA syndrome required a thorough examination, regular review and several investigations thus highlighting the difficulty in diagnosing SMA syndrome.

Learning points:

Unusual case SMA syndrome probably associated with PD