The prevalence of incidentally detected idiopathic misty mesentery on multidetector computed tomography: can obesity be the triggering cause?

Purpose: Misty mesentery appearance is commonly reported in daily practice, usually as a secondary finding of various pathological entities, but sometimes it is encountered as an isolated finding that cannot be attributed to any other disease entity. We aimed to assess the prevalence of cases with incidentally detected idiopathic misty mesentery on computed tomography (CT) and to summarize the pathologies leading to this appearance. Methods: Medical records and initial and follow-up CT features of patients with misty mesentery appearance between January 2011 and January 2013 were analysed. The study included cases with no known cause of misty mesentery according to associated CT findings, clinical history, or biochemical manifestations, and excluded patients with diseases known to cause misty mesentery, lymph nodes greater than a short-axis diameter of 5 mm, discrete mesenteric masses, or bowel wall thickening. Results: There were a total of 561 patients in whom misty mesentery appearance was depicted on abdominopelvic CT scans. A total of 80 cases were found to have isolated incidental idiopathic misty mesentery, giving a prevalence of 7%. The common indication for CT examination was abdominal pain. There was a slight female predominance (51.3%). 67.5% of all patients were classified as obese and 17.5% as overweight. Conclusions: The results of the present study show that idiopathic incidental misty mesentery appearance has a significant prevalence. Also, the high body mass index of these patients and the growing evidence of obesity-induced inflammatory changes in adipose tissue are suggestive of an association between obesity and misty mesentery appearance on CT. (author)