Hereditary angioedema (HAE) is caused by the deficiency of functional C1 inhibitor. Symptoms of this disease include:
- cutaneous angioedema
- abdominal pain
- laryngeal edema
59 adult patients with HAE were included in this study - 55 had any symptom due to HAE (abdominal location, 78%); 4 patients were asymptomatic.
In 11 cases, ultrasonography was performed during acute attacks. Ascites and intestinal wall swelling were found in 7, and thus diagnosis was confirmed.
C1 protein, showing subunits C1r, C1s, and the C1q tails. Image source: Wikipedia. Hereditary angioedema (HAE) is an autosomal dominant condition associated with episodic attacks of nonpitting edema. Patients with HAE have low levels of C1 inhibitor (a serine protease inhibitor). Edema is caused by unregulated generation of bradykinin.
The authors concluded that abdominal ultrasonography has been proved useful as an early tool for diagnosing the adverse effects of therapy and for confirming diagnosis in the case of an acute abdominal attack.
Usefulness of abdominal ultrasonography in the follow-up of patients with hereditary C1-inhibitor deficiency. Pedrosa M, Caballero T, Gómez-Traseira C, Olveira A, López-Serrano C. Ann Allergy Asthma Immunol. 2009 Jun;102(6):483-6.