Diagnosing HAE is not difficult in principle; however patients frequently get a wrong diagnosis primarily because of its rarity, with many doctors not coming across a single patient with this clinical picture in their entire career. Furthermore, HAE is difficult to diagnose due to its non-specific symptoms, which often resemble those of an allergy, intestinal colic or appendicitis and can lead physicians to a wrong conclusion easily. As a result, it can take a relatively long time for HAE to be diagnosed correctly. However, while the disease remains undetected, the patient could be at risk of suffocation due to acute swelling in the larynx in a severe attack or, in the case of intestinal edema, of undergoing unnecessary endoscopy or even having their appendix removed.(2,12)


Angioedema is a common symptom and most cases of angioedema are due to an allergic reaction. As a nonallergic form of angioedema, symptoms of HAE do not typically present with urticaria and are not caused by the common triggers of an allergic response or do not respond to treatments used in histamine-mediated allergic reactions, i.e. antihistamines, glucocorticoids and epinephrine.

Ultimately, a diagnosis of HAE is confirmed by laboratory tests indicating either a reduced concentration of C1-INH and/or depressed C1-INH activity. A measure of C4 antigen concentration is also important as this parameter is decreased in both HAE types I and II. Assaying C1q concentrations is necessary to differentiate between HAE and acquired angioedema, a non –inherited form of angioedema associated with a C1-INH deficiency due to a chronic and/or serious illness.(2,11,21,25)

Diagnosis is difficult in patients who only have episodes of swelling in the intestine. Initially, further information is obtained by establishing whether anyone else in the patient’s family has had the disease (known as family history). However, only a laboratory analysis can provide final confirmation.


Thu, 2014-04-03

Dyax Receives FDA Approval to Expand Use of Kalbitor(R)

Thu, 2014-03-27

From the Shire 2013 Annual Report

Fri, 2014-03-14

Dyax Announces Pricing of $74 Million Public Offering of Common Stock

Tue, 2014-03-04

Patient Satisfaction and Convenience Increased with Current HAE Treatment Options, According to Study Findings

Mon, 2014-03-03

BioCryst Presents BCX4161 Phase 1 Trial and Kallikrein Inhibition Assay Results

Fri, 2014-02-28

More travel grants for HAE Global Conference 2014 now available

Newsletter Teaser ( In News Section on Homepage )


Make sure to stay updated. HAEi will keep you informed when you sign up for our newsletter.

Sign up for HAEi Newsletter and register at the same time.

Join our Facebook group - and follow HAEi on Twitter

Facebook logo SFacebook logo STwitter logo STwitter logo S



Fri, 2014-05-16 (All day)

2014 hae day :-)

On 16 May 2014 patient organizations throughout the globe will hold events, meetings, and fundraisers to support the global awareness day hae day :-)

Thu, 2014-05-15 12:00 - Sun, 2014-05-18 12:00

2014 HAE Global Conference

Venue: Hyatt Regency Reston, 1800 Presidents St., Reston, VA 20190, United States of America
Language: English

HAEi - International Patient Organization for C1 Inhibitor Deficiencies cordially invites you to attend the 2014 HAE Global Conference which will take place in Washington DC, 15 - 18 May 2014.

Registration for the conference is now open! Registration will take place on a first come, first serve basis – and since we again offer some extremely attractive registration rates and conditions, please do not wait too long registering for this exciting conference.

Please register here


Homepage Teaser 6, 2nd row right

HAE Global Community

Be part of the HAEi Community

HAEi is here to help you. Therefore we have created the HAEi Community that gives you all the bells and whistles you know from other social media (such as Facebook) and even a very sophisticated Forum, where you can discuss with fellow HAE patients and care givers. The only difference is - that here your information stays safe - and will only be shared with other HAE patients and care givers. If you are a HAE patient or directly related to a HAE patient we urge you to register today - and become an important member of our community

Help yourself and stay updated by registering already today - then you will be the first to know.....

Do you have Questions?
You can find answers on our FAQ-Page or
send us an e-mail to: info@haei.org
or go to the contact form page

Experiencing browser problems?

Our website is working properly on most web browsers. However, we know that the site will not perform correctly on Microsoft Internet Explorer version 6 and earlier! So if you are using Internet Explorer from Microsoft please ensure that you have version 7 or higher!

See the video from the 2012 HAE Global Conference in Copenhagen

Click here

HAEDAYHAEDAYLook out for next hae day :-) on 16 May 2014