Purpura is a common condition in hemorrhagic diseases. Clinically, blood spills under the skin and mucous membranes, and there are cyanosis, sputum spots, and ecchymoses. The pressure is not faded, often accompanied by snot, gums, and even hematemesis, blood in the stool, and blood in the urine. The diseases that cause subcutaneous hemorrhage are collectively referred to as purpura, most of which are allergic purpura caused by vascular disorders, and primary thrombocytopenic purpura caused by thrombocytopenia.

Allergic purpura, in allergic allergic reactions (allergies) is a systemic acute reaction, an allergic disease caused by the injection of horse serum to treat diphtheria. Similar to the symptoms of this blood vessel purpura. So use the allergic purpura to name it. Children's purpura, also known as purpura, is a common disease in children with hemorrhagic diseases. Clinically, blood spills under the skin and mucous membranes, and there are defects such as sputum and ecchymosis. The disease occurs mostly in school-age children, and is common in Western medicine such as thrombocytopenic purpura and allergic purpura.



The direct cause of the disease is often difficult to determine, and its related factors are:

First, infection: bacteria (the most common upper respiratory tract infection caused by -hemolytic streptococcus, in addition to Staphylococcus aureus, pneumococcal, Mycobacterium tuberculosis), viruses (rubella, chickenpox, measles, flu) and intestinal parasitic insect.

Second, food: fish, shrimp, crab, eggs, milk and other foods of heterosexual protein.

Third, drugs: antibiotics (cyan, chain, red, chloramphenicol), sulfonamides, isoniazid, antipyretic analgesics (salicylic acid, phenylbutazone, quinine, etc.).

Fourth, other: such as cold, pollen, insect bites, vaccination and so on. The above factors cause the antigen-antibody complex to react, which deposits on the blood vessel wall or the glomerular basement membrane, activates complement, releases allergens, etc., damages capillaries, arterioles, causes extensive capillary vasculitis, and even appears Necrotizing arteriitis causes increased permeability and fragility of the blood vessel wall, resulting in hemorrhage and edema of the subcutaneous tissue, mucosa and internal organs. Similar changes can be made to the gastrointestinal tract and joints. Most of the renal lesions are focal mild nephritis. In severe cases, there may be glomerular capillary necrosis or total renal involvement.


an examination

Related inspection

Skin color anti-platelet antibody beam arm assay specific IgE antibody

The disease belongs to the category of blood syndrome and should be differentiated from the spotted rash caused by warm disease. The occurrence of hyperthermia is related to the abnormality of the four times. Every contagious, first sees high fever, headache, and then sees a rash, the onset is acute, the transmission is fast, and even coma and convulsions.

Laboratory examination: if thrombocytopenia, prolonged bleeding time, normal clotting time, poor blood clot systolic, positive anti-platelet antibody test, positive beam arm test, suggestive of thrombocytopenic purpura; platelet count, bleeding time, clotting time and blood clot If the contraction is normal, it is prompted by allergic purpura.


Differential diagnosis

1, aspirin-like defects: is an autosomal dominant hereditary disease, platelet release dysfunction. Patients were particularly sensitive to aspirin, platelet counts were normal, and pF-3 was not effective. Clinically, the distribution of skin sputum is uneven, mucosal bleeding is obvious, and bleeding is more serious during trauma or surgery.

2, light vascular pseudohemophilia: mucosal or visceral bleeding. In some patients, the bleeding time was prolonged, the aspirin tolerance test was positive, VIII: C was decreased, VIIIR: Ag was decreased, platelet adhesion rate was decreased, and platelet aggregation with ristocetin was weakened.

3, allergic purpura: is an vascular allergic hemorrhagic disease, which is also an immune vascular disease. Frequent symptoms of fever, infection and general malaise. The symmetry of the limbs, the purple sputum appearing in batches, the ecchymoses and the sputum are mainly the hand and foot. Often accompanied by abdominal pain. Joint pain or swelling, blood in the stool, some patients have symptoms of hematuria and edema. The platelet count, clotting time, and blood clot retraction test were normal in the laboratory examination, and the bone marrow examination was not special, and the beam arm test was positive.