Predictors of Superior Mesenteric Artery Syndrome: Evidence from a Case-Control Study.

Introduction Superior mesenteric artery (SMA) or Wilkie's syndrome is a rare condition arising due to compression of the third part of the duodenum between the abdominal aorta and the superior mesenteric artery. It is important to explore factors which help in suspicion and early diagnosis of the condition. The aim of this study was to find out if measurements of aortomesenteric angle and distance can predict the occurrence of SMA syndrome. Another objective was to find out if the BMI was correlated with the aortomesenteric angle and distance of the patients. Methods A retrospective hospital-based case-control study was conducted in Qimat Rai Gupta Central hospital, Haryana, India from 2018-2020. Out of total 2100 records of acute and chronic abdominal pain patients, only seven cases of Wilkie's syndrome were confirmed via Contrast-Enhanced Computed Tomography (CECT). Information on age, gender, BMI, duration of symptoms, clinical presentation, aortomesenteric angle, and distance was compared among three groups: Group I-SMA syndrome patients (N=7), Group II- acute abdominal pain patients (N=14) and Group III- chronic abdominal pain patients (N=14). Results The hospital prevalence of Wilkie's was found to be 0.3%. The median age of patients in Group I corresponded to 26 years as opposed to Group II (31.5years) and Group III (30.5 years). There was a statistically significant reduction in the aortomesenteric angle and distance of Group I patients (22º, 6mm) as compared to both Group II (52.5º, 11mm) and Group III patients (52º, 11mm). A moderate correlation of BMI was found with aortomesenteric angle (r=0.479) and distance (r=0.357). Conclusions There was a significant reduction in the aortomesenteric angle and distance of the SMA patients as compared to both patients having acute and chronic abdominal pain. The BMI of patients was positively correlated to aortomesenteric angle and distance to the moderate level. Thus BMI along with aortomesenteric angle and distance can predict the presence of SMA syndrome.