Urticaria

Urticaria, also known as hives, is a skin condition. Itchy, pale to reddish wheals develop on the surface of the skin. These are coin-sized swellings that appear singly or which can merge into larger areas. But it may also develop into a painful, water retention-related swelling of the hypodermis (angioedema). Hives and angioedemas may occur simultaneously.

Urticaria can be acute or chronic. While the acute version fades away within 6 weeks, the chronic form lasts for over 6 weeks. With chronic urticaria, a distinction is drawn between the spontaneous and induced forms.

• There is normally no specific trigger for spontaneous urticaria. This is then also referred to as idiopathic urticaria.
• The induced form is caused by external influences such as UV light, friction, heat or cold.

Chronic urticaria can be very stressful and restrict a person’s everyday and working life. People with chronic urticaria sometimes also develop depression or anxiety.

Urticaria is not infectious.

Over half of all patients with spontaneous, chronic urticaria develop wheals and an angioedema. Around a third only get wheals, while about every tenth sufferer only gets an angioedema.

Wheals have these characteristics:

• There is a central swelling which can vary in size and is almost always surrounded by a reddening of the skin (erythema).
• The skin itches, and sometimes there is a burning sensation on the skin.
• The redness goes pale within 30 minutes to 24 hours. 

With an angioedema:

• there is a sudden, noticeable, red swelling.
• there is sometimes pain, and sometimes the skin itches.

The swelling goes down after about 72 hours. 

The wheals and angioedemas that are typical of urticaria are caused by increased activity by mast cells – a group of immune cells. These form more of the messenger histamine, which causes the blood vessels to widen and become more permeable, for example for water. This leads to rednesses on the skin and swellings in the deeper layers of the skin.

In 30 to 50 percent of all patients with acute urticaria there are no specific causes. In the others, the cause often lies in infections with rotaviruses or cold viruses, or bacteria such as streptococci. But allergic reactions to cow’s milk, latex, bee stings, pollen or animal hair may also be causes. Certain medications to combat rheumatism or high blood pressure can also cause urticaria.

So-called autoimmune reactions also play a role in some cases, i.e. the immune system acts against the body’s own healthy tissue. In the process, certain antibodies, Immunoglobulin E (IgE) to be precise, are formed which cause mast cells to be activated and a more powerful defensive reaction.

As well as infections or cancers, conditions such as gastritis, a reflux illness, or bile duct or gall bladder inflammations, can potentially strengthen the tendency to urticaria.

Induced urticaria is less common. It is triggered by external irritants such as cold, heat, pressure or sunlight.

Around 9 to 20% of the population will develop urticaria at some point in their lives. Urticaria occurs in every age group. Most illnesses occur between the ages of 20 and 40.

The chronic form affects up to 5 percent of the population, women twice as frequently as men.

The spontaneous chronic form occurs around two to three times as often as the induced form, i.e. the type caused by external influences.

The illness can be acute or chronic. Medical practitioners speak of acute urticaria when the symptoms last less than 6 weeks. When they last over 6 weeks, it is referred to as chronic.

To diagnose urticaria correctly it is important to first rule out other conditions with similar symptoms, such as urticarial vasculitis, medication allergy or contact dermatitis, as well as any severe inflammatory condition.

Finding out how badly the condition is affecting the person’s quality of life is also important. To do this, doctors can use special questionnaires that are tailored to the symptoms.

No specific tests are normally required in the case of acute urticaria. A detailed discussion with a doctor is important. The doctor will ask, for example, whether:

• the wheals or angioedemas have been there long, or if they have ever previously occurred in the person themselves or the person’s family
• the symptoms are accompanied by bone and joint pain or stomach cramps
• the sufferer has any chronic inflammatory condition such as rheumatoid arthritis, any infection or any food allergy
• the person is taking any painkillers containing acetylsalicylic acid (ASS)
• the person is using certain medications to combat rheumatism or high blood pressure
• the person has just been on holiday, and what the person does with their leisure time
• the person is suffering from stress

Depending on the type of urticaria, further tests may be useful, for example in detecting any hidden inflammations in the body or finding out any allergic causes.

The treatment aims to identify and shut out the urticaria triggers, and to alleviate the symptoms as far as possible.

Medications from the oral antihistamine group are used to treat acute urticaria. They are drugs with an anti-allergy effect and which are taken in tablet form.

When symptoms are severe or when antihistamines are ineffective, doctors can either increase the dose of the antihistamine or use other drugs. These include anti-inflammatory corticosteroids or antibodies.

In treating the chronic form, it is also important to look for the triggers. For example, it may be that people with spontaneous chronic urticaria take medications that seem to make the condition worse. These medications include, for example, painkillers containing acetylsalicylic acid (ASS) or certain drugs used to combat rheumatism and high blood pressure. In such cases, sufferers are advised to work with the doctor to look for alternatives. 

Self-help groups offer people with urticaria and their relatives the opportunity to get information and advice, and to share personal experiences. 

You can find suitable self-help via a database on the National Contact and Information Point For Encouraging and Supporting Self-Help Groups (NAKOS) website.

Chronic urticaria should be treated by an experienced skin specialist. The experience of the specialist may be determined by asking questions in the medical practice concerned.

There is more information on urticaria at allergieinformationsdienst.de (in German).