CO-EXISTENCE OF SUPERIOR MESENTERIC ARTERY SYNDROME WITH NUTCRACKER SYNDROME – A DIAGNOSTIC DILEMMA

Abstract The third section of the duodenum is compressed between the aorta and the superior mesenteric artery (SMA), which is also referred to as Wilkie syndrome or superior mesenteric artery syndrome. This is a very uncommon condition, with a frequency ranging from 0.13% to 0.3% and a preference for young women who are generally slim [1]. Weight loss, which reduces the fat plane that is located between the duodenum and the small bowel aorta [2], is the most common cause of this condition. There is a correlation between the clinical presentation and radiologic alterations, such as duodenal dilatation with the presence of an acute angle of takeoff of the SMA [3] which is used for diagnosis.Nutcracker syndrome (NCS) is characterised by its compression of the left renal vein (LRV) between the superior vena cava (SMA) and the aorta in an anterior manner, or, less frequently, between the aorta and the vertebral column in a posterior manner. Case report: 15-year-old boy that presented with pain abdomen since 6 days, associated with nausea and vomiting since 6 days. Physical examination and labs were unremarkable.CT revealed two renal veins, anterior and posterior to aorta with their compression confirming diagnosis of nutcracker syndrome. Additionally,the aortomesenteric distance, it was found to be 7 mm with aortomesenteric angle of 15 degrees, confirming the diagnosis of a co-existent SMA syndrome. Discussion: The mechanism of SMA is duodenal blockage, which results in postprandial abdominal pain that is alleviated by vomiting and an inability to accept oral intake.Two of the congenital anatomical alterations that have been proposed as potential causes to the development of the syndrome are a low takeoff of the SMA and a high insertion of the ligament of Treitz.It has been observed that the usual aorto-mesenteric angle is between 28 and 65 degrees, and the normal aorto-mesenteric distance is between 10 and 34 millimetres.The issue of diagnosing SMA syndrome has always been there due to the absence of a single test that is specifically designed for this condition.Similarly, for nutcracker syndrome, hallmark of NCS is the aggravation of symptoms with position, as standing upright causes the viscera to drop down thus pulling the SMA and aggravating the compression [17]. The diagnosis can be made by Doppler ultrasound, CT scan, or MRI where a dilated vein with a delayed washout and pelvic varicosities.Majority of cases are cured by the management, which focuses on nutritional support and weight regain strategies. Conclusion: SMA syndrome with nutcracker syndrome- in the presence of two left renal vein is a very rare occurrence, and makes the diagnosis challenging. Hence, a high incidence of suspicion is necessary to diagnose multiple anomalies on imaging.