Clinical Characteristics and Outcomes of Acute Mesenteric Ischemia in Young Adults: A KASID Multicenter Study.

Background/Aims: Acute mesenteric ischemia occurs mainly in elderly individuals; however, it can also affect young adults, and some of these patients experience a poor disease course because of delayed diagnosis and treatment. This study aimed to assess the clinical characteristics and outcomes of young adults with acute mesenteric ischemia. Methods: We retrospectively reviewed young adult patients aged 20 to 39 years diagnosed with acute mesenteric ischemia between 2002 and 2022 at four tertiary medical centers in Korea. Their clinical characteristics were compared with those of young middle-aged adults aged 40 to 49 years. Results: A total of 86 patients were included. The median age of the patients was 42 years, and 71% of the patients were male. Twenty-three percent of the patients had a history of abdominal procedures or surgery. The most common cause of acute mesenteric ischemia was mesenteric venous thromboembolism (33.7%), followed by mesenteric artery thromboembolism (30.2%), nonocclusive mesenteric ischemia (18.6%), and mesenteric artery dissection (17.4%). Patients aged 20 to 39 years were more frequently affected by mesenteric venous thromboembolism (44.0% vs 26.0%) and less frequently affected by mesenteric arterial thromboembolism (13.9% vs 42.0%) than patients aged 40 to 49 years (p=0.013). However, no significant differences were observed in terms of disease involvement, treatment method, or treatment outcome during follow-up (median, 769 days). Conclusions: Young adults with acute mesenteric ischemia may exhibit clinical characteristics distinct from those of young middle-aged adults. Venous thromboembolism is prominent etiology of acute mesenteric ischemia in young adults.