Symptoms, course, and complications of abdominal attacks in hereditary angioedema due to C1 inhibitor deficiency.

Recurrent abdominal attacks belong to the cardinal and most distressing symptoms of hereditary angioedema (HAE) due to C1 inhibitor deficiency. They are characterized by crampy pain, but may include vomiting, diarrhea, and other features. Detailed clinical data about the symptoms and course of abdominal attacks have not been reported.We retrospectively observed a total of 33,671 abdominal attacks in 153 patients with HAE including a prospectively examined subgroup of 23 patients. Symptoms, course, frequency of attacks, and complications were analyzed.The relation of mild, moderate, and severe attacks was 1:1.4:5.6 in the prospective part of the study. Extra-abdominal symptoms preceded the a…