There are many different disorders that involve vasculitis. Each one of the types of vasculitis tends to involve certain characteristic blood vessels.
Anaphylactoid purpura results in skin rash that is most evident behind your lower extremities and over your buttocks. The blood vessel inflammation that develops may result in bleeding into your skin. This bleeding causes a purplish skin rash (purpura) that can last up to several weeks.
Although anaphylactoid purpura can develop in anyone at any age, it occurs most often in children who are from ages 2 to 11, with ages 5 to 7 being the ages when it is most likely to develop. In fact, anaphylactoid purpura is the most common vasculitis that develops in children.
Boys are more likely to have anaphylactoid purpura than girls are. It occurs more often in Asians or whites than it does in blacks.
The cause of anaphylactoid purpura is unknown at the present time. Researchers believe that an upper respiratory infection like a common cold is what usually triggers this condition. The blood vessel inflammation (vasculitis) may result from an immune system response to whatever the triggering agent may be. Anaphylactoid purpura is not contagious. However, the triggering agent for the condition may be.
There are other possible triggering agents for anaphylactoid purpura. Some of these include:
- Insect bites
- Certain medicines like some types of antibiotics and antihistamines
- Bacterial and Viral infections like strep throat
- Certain vaccinations, such as the one for measles.
There are three primary signs and symptoms that are caused by anaphylactoid purpura. However, not everyone experiences all three. They are:
- Rash (purpura). This involves reddish-purple spots that can appear like bruises or be raised. You may also have angioedema or hives.
- Abdominal pain. About 50% of those with this condition have gastrointestinal signs and symptoms. The most common one is abdominal pain that can be severe. Other gastrointestinal signs and symptoms include nausea, vomiting and bloody stools or urine.
- Sore, swollen joints (arthritis). Knees and ankles are the joints that are most often affected by this condition. This affects 60 to 80% of the people with this condition.
You may also have fever with these signs and symptoms.
You or a loved one may have anaphylactoid purpura. Anaphylactoid purpura and/or complications that have developed from it or other illnesses that you have in conjunction with this condition may have resulted in the disability of you or your loved one and be what is keeping you from being able to work.