Allergic purpura is not actually an allergy
There are many types of purpura, most of which are caused by low platelets due to various reasons. However, there is a type that is prevalent in children under 10 years old called “allergic purpura.” This is an immune system disease caused by a cold virus.
Although allergic purpura is called “allergic,” it is not a reaction to anything specific. It is caused by the cold virus mutating the patient’s antibodies, which then attack the blood vessels, resulting in systemic vasculitis. Inflamed blood vessels can cause microvascular rupture, leading to purple spots on the epidermis and pain and swelling in different organs.
The most important thing to pay attention to in purpura is the “kidney invasion”
Vasculitis causes purple spots, which occur most commonly in the lower limbs due to blood flow rate. Children may complain of sore feet, and the spots will appear one after another. Almost all patients will have purple spots. A doctor can quickly diagnose and treat it by ruling out other possible causes of purpura.
Most patients with vasculitis have swollen joints because blood accumulates in the joints. Additionally, the abdomen has many microvessels, which can cause pain and possible intestinal bleeding. However, these symptoms may not occur simultaneously, and if abdominal pain and rectal bleeding occur first, it may be misdiagnosed as an intestinal disease. Therefore, it is essential to inform the doctor as soon as purple spots appear for a new diagnosis.
However, the most crucial thing to pay attention to is that vasculitis can cause poor kidney metabolism. Forty to fifty percent of patients develop nephritis with proteinuria, hematuria, edema, peritonitis, and the most severe case can be life-threatening. Antibody attacks may take a long time to appear, so patients must undergo 3-6 months of kidney monitoring to avoid missing the treatment period.
How to treat allergic purpura
Most patients with allergic purpura can recover within 4 weeks. Currently, few invasive therapies exist, and non-steroidal anti-inflammatory drugs are mainly used to relieve pain. If patients have intestinal or kidney involvement, corticosteroids or immunosuppressants may be used as needed. The prognosis is good in 90% of cases.
However, 60% of patients will experience 1-2 recurrences, but the symptoms will be milder. By following the doctor’s treatment instructions, patients can still recover with almost no long-term effects. However, if it progresses to nephritis, it may lead to irreversible kidney function loss.
While the incidence of kidney involvement is not high, occurring in only about 2% of patients, 8% of these patients will progress to kidney failure. As allergic purpura mostly occurs in young children who may not be able to communicate their symptoms clearly, parents should pay special attention and conduct long-term monitoring.