Anaphylactoid purpura rash occurs directly beneath the skin surface due to the abnormal reaction between the antibodies – created by the body to suppress some of the substances that entered into the system – and blood vessels. The blood vessels are inflammed and become porous, creating a rash. In most cases, antibodies suppress the infection caused by Streptococcus, but can also be caused by a reaction to a food or drug.
This disorder most often affects children between the second and tenth year.
Two weeks before the rash, the baby usually has throat pain. The rash usually does not cause disturbances, and it consists of irregularly reddish-red surfaces of a size ranging from the size of the head to a stain of approximately 25 mm in diameter; rash occur on the ankles, the buttocks and the elbows. When rash occurs, some children feel generally bad and have a slightly elevated temperature. The rash is not permanently present, but usually comes and goes. Some children may have swollen joints or abdominal pain, which are often strong and persistent. Occasionally, blood is present in the stool (indicating bleeding in the intestines) or in the urine (which is a sign of kidney damage).
Anaphylactoid purpura is very rare, and is more common in boys. The major dangerous complication of this disease is permanent kidney damage. Other, less common complications are intussusception or severe bleeding in the intestines or other internal organs.
What to do?
If your child has any of the symptoms described, contact your doctor. In most cases, treatment will not be necessary because the disorder will pass by itself after one or two months, although in some children this disorder returns for up to two years before it finally disappears. If there are signs of kidney damage, doctors recommend special tests, such as kidney biopsy. To relieve very severe pain in the abdomen, the doctor may prescribe anti-inflammatory corticosteroid tablets.