What is the cause of idiopathic thrombocytopenic purpura

I believe many people don’t know much about idiopathic thrombocytopenic purpura. As an organ-specific autoimmune system exudative disease, it often manifests itself in symptoms such as skin bleeding, bleeding gums, purpura and macules.

1. Cause

ITP is currently considered to be an organ-specific autoimmune hemorrhagic disease caused by the body's production of antiplatelet autoantibodies, which leads to excessive platelet destruction by the mononuclear macrophage system, resulting in thrombocytopenia. The cause of the disease is not yet fully understood, and the pathogenesis has not been fully elucidated. The onset of ITP in children may be closely related to viral infections, including herpes virus, Epstein-Barr virus, cytomegalovirus, parvovirus B19, measles virus, mumps virus, rubella virus and hepatitis virus. Symptoms usually develop 2 to 21 days after infection. The incidence of chronic ITP in women of childbearing age is higher than that in men, and it is more likely to relapse during pregnancy, suggesting that estrogen may be involved in the pathogenesis of ITP.

2. Clinical manifestations

The onset is generally insidious, manifested by scattered skin hemorrhages and other milder bleeding symptoms, such as epistaxis, gingival bleeding, etc. Purpura and ecchymosis may occur on any part of the skin or mucous membranes, but are common in the lower and distal ends of the upper limbs. The bleeding symptoms of ITP patients are related to the platelet count to a certain extent. When the platelet count is between 20 and 50×10/L, mild trauma can cause bleeding. A small number of bleeding is spontaneous, such as ecchymosis and petechiae. When the platelet count is less than 20×10/L, there is a risk of severe bleeding. When the platelet count is less than 10×10/L, intracranial hemorrhage may occur. Physical examination usually does not reveal splenomegaly, but a few patients may have mild splenomegaly, which may be caused by viral infection.

3. Children with acute ITP may have a history of respiratory infection 1 to 3 weeks before the onset of the disease, and in a few cases it occurs after vaccination. The onset is acute, and in a few cases it presents as an explosive onset, with mild fever, chills, sudden onset of widespread and severe skin and mucous membrane purpura, and even large ecchymosis. Skin petechiae are mostly systemic, mostly on the lower limbs, and are evenly distributed. Mucosal bleeding is often seen in the nasal cavity and gums, and blood blisters may occur in the mouth. Gastrointestinal and urinary tract bleeding is not uncommon, and less than 1% of children develop life-threatening intracranial hemorrhage. If the patient has a headache or vomiting, be alert to the possibility of intracranial hemorrhage. Most patients can recover on their own, but a few will not recover and become chronic.