Wheal
| Classification according to ICD-10 | |
|---|---|
| L50.9 | Urticaria, unspecified |
| ICD-10 online (WHO version 2019) | |
As wheal is called point-to plateau-like elevations of the skin , which after mechanical irritation (such as pressing, rubbing, scratching, pricking), or chemical irritation, such as by plant toxins or insect bites , created or urticaria and allergy occur.
Appearance
A wheal occurs as a result of the increased permeability of the skin's blood vessels, which in turn is caused by an excessive release of tissue hormones - mostly histamine from the mast cells - and leads to water retention in the upper epidermis . Wheals are usually button-shaped or plateau-shaped, often paler than their surroundings and of various sizes. They can be circular or irregular in shape. Wheals are often surrounded by a red halo. Most of the time, wheals are associated with short-term or long-term itching .
Possible causes
Plant poisons
Wheals can appear after touching certain plants, such as nettles , but also tropical plants such as the nettle tree or poison sumac . In addition, the harmful plant ingredients are often immediately perceived as burning and painful and usually trigger itching a little later. However, the pollen from plants can also cause wheals and reddened skin (see hay fever ).
Insect bites
Typical symptoms of insect bites are itching and solitary wheals. Stinging insects such as fleas , flat bugs , ticks , mosquitoes , black flies , midges , horseflies or biting flies leave skin injuries, around which itchy wheals then form. These are often a reaction to anticoagulant substances of the insect with the saliva delivered the Bloodsucking easier.
Hives
Another cause of wheals can be hives ( urticaria ), a skin irritation caused by excessive histamine release as a result of stress or external influences (e.g. cold , heat or changes in air pressure ) . Hives got their name from the formation of swarms of wheals, which are reminiscent of contact with nettles. The wheals appear in hives with or without a red halo on the shoulder , stomach , thigh and forearm . The hives usually go away within minutes or an hour or two ( acute hives), but they can last longer ( chronic hives).
Allergies
Wheals can also form as an allergic reaction to a wide variety of triggers. Be it with a food allergy , a light allergy or a drug intolerance . The wheals can remain locally limited to contact areas or appear generalized, often in regions of the neck and chest as well as near the hips .
Countermeasures
If there is excessive wheal, the cause of which is not obvious, a doctor may try skin tests and laboratory tests to determine what is causing the wheal. The so-called antihistamines alone suppress the symptom. Those affected should not aggravate wheals by scratching, rather cooling the affected skin area is recommended. For nettle or insect bites, rubbing the wheals with vinegar water can bring relief.
literature
- Siegfried Bäumler: Medicinal plant practice today: portraits, recipes, application . Elsevier, Urban & Fischer-Verlag, 2006, ISBN 3-437-57270-9 .
- Stefan Nöldeke: Clinic Guide Surgical Outpatient Clinic . Elsevier, Urban & Fischer-Verlag, 2009, ISBN 978-3-437-22941-1 .
- Lothar Jäger: Allergies: causes, therapies, prevention . Beck, 2000, ISBN 3-406-44740-6 .
Web links
Individual evidence
- ↑ Alphabetical index for the ICD-10-WHO version 2019, volume 3. German Institute for Medical Documentation and Information (DIMDI), Cologne, 2019, p. 736
- ↑ a b c d Lothar Jäger: Allergies. 2000, pp. 9, 22-26, 48-52, 82-98.
- ^ A b Siegfried Bäumler: Medicinal Plant Practice Today. 2006, p. 109.
- ↑ Stefan Nöldeke: Clinic Guide Surgical Outpatient Clinic. 2009, p. 453.
