Table 1.
Differential diagnosis of intestinal angioedema
| Initial presentation | Colicky abdominal pain, nausea, and vomiting |
| Possible gastrointestinal disorders | • Appendicitis |
| • Hepatitis | |
| • Pancreatitis | |
| • Biliary obstruction | |
| • Diverticulitis | |
| Test results | |
| Biochemical | Suggestive of HAE |
| • C1-INH level of <21 mg/dL | |
| • Decreased C2 and C4 levels | |
| Rules out biliary obstruction and hepatitis | |
| • Normal serum bilirubin, ALP, and ALT levels | |
| Ultrasonography | Suggestive of HAE |
| • Bowel mucosal thickening | |
| • Ascites | |
| Computed tomography | Suggestive of HAE |
| • Massive small bowel or colonic edema | |
| • Prominent mesenteric vessels | |
| • Thickened omentum | |
| • Moderate ascites | |
| Rules out appendicitis and diverticulitis | |
| • Normal pericolic fat | |
| Rules out pancreatitis | |
| • Normally shaped pancreas | |
Notes: Data from Bork, Fischer, and Dewald;26 and Bork, Staubach, and Eckardt.30 Reproduced from Locascio EJ, Mahler SA, Arnold TC. Intestinal angioedema misdiagnosed as recurrent episodes of gastroenteritis. West J Emerg Med. 2010;11(4): 391–394.32
Abbreviations: ALP, alkaline phosphatase; ALT, alanine aminotransferase; C1-INH, C1 esterase inhibitor; HAE, hereditary angioedema.