Acu disease, also known as acquired cold urticaria (ACU), is a type of physical urticaria that occurs due to an overreaction of the body's immune system to cold exposure.
Understanding Acquired Cold Urticaria (ACU)
ACU is characterized by the release of proinflammatory mast cell mediators after being exposed to cold temperatures, leading to a variety of symptoms. The exact reasons for ACU are still being researched, but it's clear that it's a distinct reaction to cold, rather than a common allergic reaction.
Key Aspects of ACU:
- Cause: ACU is triggered by cold temperatures that lead to the release of certain substances from mast cells.
- Physical Urticaria: ACU is a subtype of physical urticaria, which means the reactions are caused by physical stimuli, like cold.
- Symptoms: The reaction can cause hives, itching, swelling, and sometimes more serious symptoms.
- Association with Diseases: Various diseases have been linked to ACU, though the specifics of these associations are still under investigation.
How ACU Manifests
The reaction to cold is not uniform, and how an individual with ACU might experience it can vary.
Possible Symptoms:
- Hives: Raised, itchy welts on the skin where cold was applied or felt.
- Itching: Intense itching often accompanies the development of hives.
- Swelling (Angioedema): In some cases, swelling can occur in deeper layers of the skin, often affecting areas like the lips, eyelids, or hands.
- More Severe Reactions: In rare instances, ACU can lead to more severe systemic reactions including fainting, rapid heart rate, or difficulty breathing.
What Triggers ACU?
ACU is usually triggered by direct exposure to cold, which can include:
- Cold air.
- Cold water.
- Cold objects.
- Consuming cold drinks or food.
Managing ACU
Managing ACU involves avoiding cold exposure and taking medication:
- Avoidance: The best way to manage ACU is to minimize or avoid exposure to cold.
- Medication: Antihistamines are often used to control symptoms.
- Epinephrine: In rare cases of severe reactions, epinephrine may be required.
Summary
| Aspect | Description |
|---|---|
| Definition | Acquired cold urticaria, a subtype of physical urticaria, caused by cold exposure. |
| Cause | Release of proinflammatory mast cell mediators due to cold. |
| Triggers | Exposure to cold air, water, objects, food or beverages. |
| Symptoms | Hives, itching, swelling; potentially more severe systemic reactions. |
| Management | Avoiding cold, antihistamines, epinephrine for severe reactions. |
