Hereditary angioedema – rare but distressing

Swelling, like fever, can occur in different situations and for different reasons - so diagnosing it can be difficult. Symptoms of this type are often harmless but annoying, for example when caused by an insect bite. Sometimes they can also be a sign of serious cardiovascular or kidney disease. However, there are other dangerous swellings, the occurrence of which can acutely threaten the life of the patient, and due to their extent they almost always cause severe pain and discomfort.

Such painful, large swellings that do not respond to conventional treatments can be a symptom of hereditary angioedema, also known as HAE. Although the diagnostic process itself is not very complicated, it takes an average of twelve years from the first symptoms to the correct diagnosis. This is mainly due to the low awareness of the disease due to its rarity. The frequency of occurrence is between 1:50.000 and 1:100.000. This means that there are probably well over a thousand people affected in Germany alone - mostly undiagnosed, which makes more accurate estimates difficult.

The first symptoms of HAE usually appear in the second or third decade of life, but there are patients who have an earlier onset, even in infancy, or later. The symptoms of this disease are often mistaken for allergic reactions, but conventional antihistamines or glucocorticosteroids do not bring relief in such cases.

“In connection with hereditary angioedema we speak of swelling attacks that grow continuously and quite quickly to enormous sizes within a few hours. Except for the lack of response to the usual treatment with antihistamines and glucocorticosteroids, swelling usually differs from those characteristic of allergies in that it is not accompanied by itching and urticaria or reddening of the skin. It is also typical that the swelling associated with HAE subsides on its own within 3 to 5 days. Bouts of swelling in hereditary angioedema may affect the skin or subcutaneous tissue. In the latter case, they are often very dangerous for the patient due to the involvement of the pharynx, larynx, digestive tract or urinary tract - they can cause complete obstruction of the airways as well as severe abdominal pain and vomiting due to intestinal obstruction or partial intestinal obstruction, and even lead to kidney failure," says dr medical Aleksandra Kucharczyk, specialist in internal medicine and allergology Saventic Care collaborates, an organization dedicated to diagnosing rare diseases.

Although there is no way of predicting when and in what situation a patient will experience swelling, patients report some factors that contribute to seizures. These include, for example, surgical or dental procedures, infections, minor injuries, psychological factors (stress) and, in women, hormonal changes.

Hereditary Angioedema - When to Review a Diagnosis?

HAE is a rare condition affecting approximately 1 in 50.000 people worldwide. The probability that there are sick people in our environment or that we get sick ourselves is therefore low, but cannot be ruled out. Many patients are still undiagnosed.

“Hereditary angioedema is a disease that is genetic in about 80 percent of patients, so symptoms often appear in other family members. In the remaining cases, it is caused by a new mutation of the gene. Characteristic symptoms (the occurrence of massive swelling) arise from increased permeability of the blood vessels, which is caused by increased levels of bradykinin. The excessive production of this protein, in turn, results from a deficiency or abnormal function of the C1 esterase inhibitor – an important protein involved in clotting processes, the formation of kinins and the activation of the complement system. Hereditary angioedema was first described by Heinrich Quincke in 1882, but it was not until the 1960s that researchers Donaldson and Evans elucidated the pathogenesis of the disease presented here. Understanding the causes of the disease has led to the development of many effective drugs," explains Dr. medical Aleksandra Kucharczyk.

HAE should be suspected in patients with the symptoms described above, i.e. recurrent massive swelling in various parts of the body, unexplained abdominal pain or edema of the neck, which persists for 3 to 5 days despite conventional treatment and then resolves spontaneously. This is especially true 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 who find a reduction in C1 inhibitor levels (type I HAE) or its activity (type II HAE) and often a reduction in the C4 complement component.

Because of the rarity of HAE, presenting symptoms or test results will not always draw a doctor's attention to this diagnosis. In such cases, patients can turn to organizations that help diagnose rare diseases and analyze symptoms more comprehensively.

When to see a doctor and is HAE treatable?

If you have swelling or abdominal pain, the causes of which are unknown, it is definitely always advisable to consult a doctor. Although HAE attacks do not pose a health threat in most cases, they can be tragic in the abdomen or throat. Therefore, rather than ignoring the symptoms, it is better to have a thorough diagnosis performed.

“Although there is no cure for the disease, there are currently many drugs available that not only provide rapid relief from swelling, but also prevent it from occurring. Therefore, diagnosis of the disease allows for appropriate treatment, improves patient comfort, and often saves their life as well. A quick response is highly relevant, especially in the case of severe, life-threatening seizures. Long-term prophylaxis, which is now available, is particularly important for people with frequent life-threatening seizures. In this case, regular intake of medication every 2-4 weeks will lead to the complete elimination of all symptoms of the disease," explains Dr. medical Aleksandra Kucharczyk.

Early diagnosis of HAE patients is key to ensure their safety and quality of life. So it's definitely not worth ignoring worrisome symptoms in yourself or loved ones, but starting the diagnostic process and getting answers to your nagging questions. Among the organizations specializing in the detection of some rare diseases is Saventic Care, who evaluate your medical records for symptoms that match HAE.

Source: Press article Saventic Health from May 16.05.2023, XNUMX