Statistics from Altmetric.com
A 27 year old HIV positive man with a CD4+ lymphocyte count of 26 cells ×106/l presented with a 2 week history of progressive left sided weakness, vomiting, and weight loss. A computed tomograph (CT) brain scan demonstrated ring lesions bilaterally in the basal ganglia. Toxoplasma serology was positive at a titre of 1:256 and treatment for cerebral toxoplasmosis commenced. His weakness responded to therapy but vomiting continued despite antiemetics. An ultrasound scan demonstrated an enlarged, dilated stomach, dilated first and second parts of the duodenum, and an obstruction at the level of the third. Barium studies confirmed these findings but also demonstrated prominent peristalsis in the second part of the duodenum and an abrupt cessation of flow to barium in the middle of the third (fig 1). Some flow of barium into the jejunum was noted when the patient was turned prone. An abdominal CT scan demonstrated a reduction in the angle between the superior mesenteric artery and the aorta (fig 2). A diagnosis of superior mesenteric artery (SMA) syndrome was considered. Two litres of bile were aspirated per nasogastric tube daily and he continued to lose weight. His body mass index (BMI) fell to 12 and total parenteral nutrition was introduced for 6 weeks after which an exploratory laparotomy was performed. An anterior gastrojejunostomy was made and a jejunal feeding tube inserted into the collapsed proximal small bowel. The patient recovered postoperatively but continued to vomit after meals. After 4 weeks his BMI increased to 15, vomiting stopped, and he demanded food. At the time of writing he is well, independent, and on antiretroviral therapy.
Superior mesenteric artery syndrome is a controversial diagnosis synonymous with vascular compression of the duodenum, arteriomesenteric duodenal compression syndrome, the cast syndrome, chronic duodenal ileus, and Wilkie’s syndrome. First described by Rokitansky in 1842, frequency of reports have recently declined and its existence debated.1 The syndrome has been ascribed to a reduction in the angle between the aorta and the superior mesenteric artery, scissoring the duodenum in its third part causing obstruction. This is often because of sudden, severe weight loss resulting in a reduction of mesenteric and retroperitoneal fat. Precipitating factors include eating disorders, severe wasting conditions, prolonged immobilisation, previous abdominal surgery, or inflammatory conditions. It has also been reported in cases of severe kyphoscoliosis.2 It has not previously been reported in AIDS.
Characteristic symptoms, typically intermittent in nature, comprise bloating, nausea, and intractable bilious vomiting relieved by adopting the prone or knee to chest position. A barium meal is the most useful diagnostic investigation. Features of note include dilatation of the first and second parts of the duodenum and an abrupt, linear hold up of flow to barium in the third with abnormal peristalsis and even reverse peristalsis frequently observed. Relief of the obstruction can in some instances be achieved by placing the patient prone during the investigation.1–3 CT studies can demonstrate reduction in the aortosuperior mesenteric artery angle and serve as a non-invasive diagnostic tool.4
Reversal of weight loss is key to resolution, by surgical means if necessary. Nutritional support should be attempted first. Endoscopic or nasogastric decompression is often difficult because of severe gastric dilatation. Duodenojejunostomy or gastrojejunostomy are the surgical procedures of choice when medical therapy fails.2,3 Our patient did not experience immediate symptomatic relief through surgery but did achieve rapid weight gain via jejunal feeding. We report the first case of SMA syndrome in a patient with AIDS. The spread of HIV worldwide and its association with severe wasting makes this an important differential diagnosis for the clinician.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.