title: Bowel Angioedema Associated With Iodinated Contrast Media: Incidence and Predisposing Factors.
abstract: Bowel angioedema is an acute adverse reaction to iodinated contrast media (CM) that involves the gastrointestinal tract. We aimed to investigate the incidence and predisposing factors of iodinated CM-associated bowel angioedema during computed tomography (CT) examinations.
  
  
  
  This study was approved by our institutional review board, and informed consent was waived due to its retrospective design. From July 2013 to July 2015, adult patients with a history of adverse reactions to iodinated CM during CT (group A, n = 427) and patients without adverse reactions matched for age and sex with the propensity-score matching method (group B, n = 427) were studied. Contrast media-associated bowel angioedema was determined when bowel wall thickness increased after contrast enhancement compared with the precontrast scan. Potential predisposing factors including patient demographics, symptoms and time of adverse reactions, and CM-related factors were compared between patients with and without angioedema in group A. In addition, the incidence of bowel angioedema was compared between groups A and B.
  
  
  
  The incidence of CM-associated bowel angioedema in group A was 3.3% (14/427) in the per-patient analysis and 2.6% (15/578) in the per-examination analysis. The CM-associated bowel angioedema involved the distal duodenum and/or proximal jejunum and showed long-segmental circumferential bowel wall thickening on CT. None of the studied predisposing factors was different between patients with and without bowel angioedema (P > 0.05). The incidence of CM-associated bowel angioedema in group B was 1.9% (8/427) and 1.7% (8/458) for per-patient and per-examination analyses, respectively, and these rates were not significantly different between groups A and B (P = 0.346 and P = 0.370, respectively).
  
  
  
  The incidence of CM-associated bowel angioedema during CT was 1.7% to 3.3%, and none of the studied predisposing factors was associated with bowel angioedema.
authors.affiliation: From the *Department of Radiology, Severance Hospital, and †Biostatistics Collaboration Unit, Department of Research Affairs, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Nieun
authors.initials: N
authors.lastname: Seo
authors.forename: Yong Eun
authors.initials: YE
authors.lastname: Chung
authors.forename: Joon Seok
authors.initials: JS
authors.lastname: Lim
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Song
authors.forename: Myeong-Jin
authors.initials: MJ
authors.lastname: Kim
authors.forename: Ki Whang
authors.initials: KW
authors.lastname: Kim
mesh_terms: D000799:Angioedema / Q000139:chemically induced* / Q000503:physiopathology; D003287:Contrast Media / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D007410:Intestinal Diseases / Q000139:chemically induced* / Q000503:physiopathology; D007455:Iodine / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media; D007455:Iodine