Children and young people are prone to allergic purpura. How to treat it? What should we pay attention to?

Author: Chen Wenming, Chief Physician, Beijing Chaoyang Hospital, Capital Medical University

Reviewer: Duan Yanlong, Chief Physician, Beijing Children's Hospital, Capital Medical University

In our traditional understanding, allergies are itchy skin and rashes, which can be cured by taking anti-allergic drugs. But in fact, in severe cases, allergic purpura will occur.

1. What is Henoch-Schönlein purpura?

Allergic purpura is an allergic reaction caused by the body's contact with allergic substances. Patients with allergic purpura will develop skin purpura due to dilation, congestion and edema of subcutaneous blood vessels, and red blood cells will leak out of the blood vessels.

Moreover, this allergic reaction can not only manifest itself on the skin, but may also damage the joints and other tissues and organs.

For example, patients may experience arthritis and joint pain, because the joints may also become allergic and congested and swollen, and patients may limp and have difficulty walking;

In addition, the capillaries in the gastrointestinal tract are congested and edematous, which may cause some digestive tract symptoms, such as abdominal pain, diarrhea, blood in the stool, and even intestinal perforation and intestinal obstruction.

When the renal blood vessels dilate and become congested, it will cause kidney damage, such as hematuria and proteinuria. Over time, 20% of patients may develop chronic nephritis.

These are some typical manifestations of the so-called allergic purpura.

Figure 1 Original copyright image, no permission to reprint

Epidemiological surveys show that children aged five to six, seven to eight are at high risk of developing Henoch-Schonlein purpura, because after the age of teens, the immune function is basically sound and the probability of developing Henoch-Schonlein purpura is not very high.

Then there are young and middle-aged people, who are also more likely to have this kind of allergic reaction because at this age, the body's immune system is in a very active state, and allergic reactions are very likely to occur in this state.

On the contrary, allergic reactions are less likely to occur in older people or those with weakened immune systems.

2. How to treat allergic purpura?

The main treatment for allergic purpura is anti-allergic therapy.

For general skin rashes, or some mild arthritis, the joint pain is not very severe, or the patient simply presents with hematuria, no proteinuria, and no obvious kidney damage. This kind of mild allergic purpura is generally treated with some anti-allergic drugs.

If the case is more serious, the rash is very severe and covers the entire body, accompanied by severe joint pain, or diarrhea, or not only hematuria but also proteinuria, then hormone treatment is needed.

In more serious cases, if hormones cannot control the condition, very few patients with severe allergic purpura need to use immunosuppressants for treatment. Because it is an immune allergic reaction, some immunosuppressants can help control the disease.

Another thing is the treatment for allergens. The ideal state is to avoid contact with allergens. If we can know what the allergen is through examination, we should avoid contact. Some allergens can be treated with desensitization therapy, which can reduce the degree of allergic reactions in the future, or even prevent allergies from occurring.

But from the current perspective, there are still very few cases where desensitization treatment can be done, so patients should try to avoid contact with allergens.

Figure 2 Original copyright image, no permission to reprint

3. What should patients with Henoch-Schönlein purpura pay attention to in their diet?

For patients with allergic purpura, they should avoid foods that are likely to cause allergies as much as possible.

If you know what you are allergic to, you can just avoid these foods. However, if you don’t know what food you are allergic to, you should try to avoid these foods that are likely to cause allergies.

The most common food that can easily cause allergies is seafood, because the protein in seafood is particularly allergenic. Eggs and milk, which are foods with a large variety of antigenic variability, are also prone to allergies. Compared with seafood, eggs, and milk, pork, beef, and mutton are less likely to cause allergic reactions.

In fact, in addition to diet, we should also reduce contact with substances that are likely to cause allergies.

Especially when the seasons change, such as during the rainy season in summer, when the air is relatively humid, you should often take out your quilts to dry them in the sun to make your home cleaner. In this case, the probability of developing a mite allergy will be lower.

Therefore, we must try our best to find allergens and avoid contact with these foods or substances as much as possible. This is an issue that we must pay attention to in our daily lives.