What is Urticaria?
The most common cause of Urticaria, a hypersensitivity reaction, is the body's production of histamine, which manifests as bright, swollen, and itchy areas on the skin. Anywhere on the body, these welts or hives may appear and persist for a few hours to many days. Chronic Urticaria can last for a long period of time and can be somewhat recurrent, even though the great majority of cases are acute and go away in six weeks.
Causes of Urticaria
Pathology of Urticaria is multifaceted and, on occasion, challenging to attribute. Here are some common triggers:-
- Allergic Reactions - Allergens including some foods (nuts, shellfish, dairy), insect stings, and drugs cause hives.
- Infections - Viral, bacterial, or fungal infections sometimes induce Urticaria, especially in childhood.
- Environmental Factors - Physical Urticaria is the cause of cold, heat, sunlight or water exposures in some patients.
- Stress and Emotional Triggers - Psychological stress can exacerbate or trigger the condition.
- Underlying Medical Conditions - Autoimmune disorders, thyroid disorders and some cancers can be associated with chronic Urticaria.
Unknown Causes - In many cases, no specific trigger is identified. This is referred to as idiopathic Urticaria.
Symptoms of Urticaria
Urticaria is characterized as the onset of welts or hives on the skin. These welts have the following characteristics:-
- Shape and Size - They can be individual, small spots, large areas, or even coalesced welts.
- Colour - Typically red, pink, or skin-toned, with a lighter centre.
- Itchiness - Urticaria is typically also characterized by severe itching, but some may suffer from burning or stinging.
- Duration - Acute Urticaria is normally resolved within 24 hr, but may recur in chronic disease.
In the more severe forms, Urticaria may be accompanied by Angioedema, deep in the skin's dermal structure, particularly affecting the eyes, lips, hands, feet, and throat.
Types of Urticaria
- Acute Urticaria - It lasts for under six weeks and is usually atopic dermatitis or infective disease.
- Chronic Urticaria - It continues for longer than 6 weeks and can develop even in the absence of a clear cause.
- Physical Urticaria - Awakened by physical stimuli such as pressure, vibration, heat, cold or sunlight.
- Dermatographic Urticaria - (Also referred to as skin writing in which hives appear as a consequence of light scratching).
