Today, 16 May, is World HAE Day. The day aims to raise awareness of hereditary angioedema among the public and patients to ensure better care for patients, as well as faster diagnosis and treatment.
Swelling is not always the result of an allergy. What is hereditary angioedema and how do you recognise it?
Swellings, like fever, can occur in different situations and for different reasons. For this reason, their diagnosis may not be easy. They are often harmless, although annoying, for example when they result from an insect bite or sting. Sometimes they can be a symptom of serious cardiovascular or renal conditions. However, swellings of a much more serious nature can be seen, the occurrence of which can threaten the life of the patient and which almost always cause great pain and discomfort to the patient by their extent.
Such painful, large swellings that do not respond to standard treatments may be a symptom of hereditary angioedema, or HAE. Although the diagnosis process itself is not very complicated, it takes an average of 12 years from the first symptoms to diagnosis. This is mainly due to low awareness of the condition due to its rarity - in Poland, less than 500 patients have so far been diagnosed with the disease.
Recurrent swelling - red alert
The first symptoms of HAE usually appear in the second and third decades of life, but there are patients who experience them earlier, even in infancy or later. The symptoms of this disease are often mistakenly treated as allergic, but the standard antihistamines or glucocorticosteroids used in such situations do not bring any improvement.
- In the context of hereditary angioedema, we are talking about attacks of oedema that gradually, quite rapidly, within a few hours or so, often builds up to enormous proportions. Apart from the lack of response to standard therapy with antihistamines and glucocorticosteroids, it differs from the swelling characteristic of allergy in that it is usually not accompanied by pruritus and urticarial lesions or reddening of the skin. It is also typical that oedema in HAE resolves spontaneously within 3 to 5 days. Hereditary angioedema attacks may involve the skin or subcutaneous tissue. In the latter case, because they involve the pharynx, larynx, gastrointestinal tract or urinary tract, they are often very dangerous for the patient - they can cause complete closure of the airways, as well as severe abdominal pain, vomiting due to obstruction or obstruction of the intestines, and can even lead to kidney failure - informs Dr Aleksandra Kucharczyk, MD, specialist in internal medicine and allergology, who cooperates with the Saventic Foundation on the diagnosis of rare diseases.
Although it is impossible to predict in which situation and when a patient will develop swelling, patients mention several factors that favour attacks. These include, for example, surgical or dental procedures, infections, minor injuries, psychological factors (stress) and, in women, hormonal changes.
Hereditary angioedema - when is it worth considering a diagnosis for this condition?
HAE is a rare disease that affects approximately 1 in 50 000 people worldwide. The likelihood that there are sufferers around us or that we have the disease ourselves is therefore low, but it cannot be ruled out. Many sufferers are still undiagnosed. In 2021, there were only 466 patients registered in the national HAE patient register.
- Hereditary angioedema is a disease that has a genetic basis in approximately 80 per cent of patients, so symptoms are most often also seen in other family members. In other cases, it is caused by a new gene mutation. The characteristic symptoms (appearance of massive oedema) are due to increased vascular permeability caused by elevated levels of bradykinin. Excessive production of this protein, in turn, results from a deficiency or abnormal function of C1-esterase (C1-inhibitor), an important protein involved in coagulation, kinin production and activation of the complement system. Hereditary angioedema was first described in 1882 by Heinrich Quincke, but it was not until the 1960s that researchers Donaldson and Evans elucidated the pathogenesis of the disease as presented here. Knowledge of the causes of the disease led to the development of a number of effective drugs - the explains Aleksandra Kucharczyk, MD, PhD.
HAE should be suspected in patients who present with the symptoms described above, i.e. recurrent, massive swelling of various parts of the body or unexplained abdominal pain or swelling of the throat that persists despite treatment for 3 to 5 days and resolves spontaneously thereafter, especially if the symptoms first appeared before the age of 40 and are also observed in other family members. Confirmation of the diagnosis requires laboratory tests. Hereditary angioedema can be diagnosed in patients with decreased levels (type I HAE) or activity (type II HAE) of C1 inhibitor, often with a concomitant decrease in C4 complement.
Because HAE is a rare disease, a patient's symptoms or test results will not always draw a doctor's attention to the possibility of a diagnosis of HAE. In this situation, patients can turn to organisations that help diagnose rare diseases and analyse symptoms more holistically.
When to see a doctor and can HAE be treated?
If you are experiencing swelling or unexplained abdominal pain that you do not know the cause of, it is definitely worth consulting your doctor. Although HAE attacks in most cases are not a health risk, their occurrence in the abdomen or throat can end tragically. Therefore, instead of ignoring the symptoms, it is better to undergo a thorough diagnosis.
- While the disease cannot be cured, a number of medications are now available that not only cause swelling to subside quickly, but also prevent it from occurring. Recognising the disease therefore allows for proper treatment, improves patients' comfort and often saves their lives. This is because rapid response is very important, especially in the case of a severe, life-threatening attack. Very importantly, people with frequent life-threatening seizures can now be offered so-called long-term prophylaxis. In this case, the systematic administration of medication every two to four weeks leads to complete resolution of all symptoms of the disease. Aleksandra Kucharczyk, MD, explains.
Early diagnosis of patients with HAE is key to keeping them safe and making their lives more comfortable. So it is definitely not worth ignoring worrying symptoms in yourself or a loved one, and instead start the diagnostic process and get answers to the questions that plague you.
Saventic Foundation was created for patients who remain undiagnosed for months or years and are looking for the right specialist or medical centre. The organisation's main task is to support faster diagnosis of rare diseases. To this end, the Foundation has created and provides, free of charge, an application through which the patient can securely submit a questionnaire and medical data. The documents received are analysed by both innovative artificial intelligence algorithms and a medical consortium specialised in rare diseases. If a risk of a rare disease is identified, the patient is informed about the centre or doctor to which he or she should go. The Foundation performs, free of charge, dry blood drop tests (DBS) for Gaucher disease, Fabry disease and mucopolysaccharidosis for patients at high risk of a rare disease. Thanks to the use of advanced technology and the involvement of experts, each case is treated individually and diagnosis time can be significantly reduced. More information: www.fundacjasaventic.pl.