(a) Disease knowledge: Immune thrombocytopenic purpura (ITP), also known as idiopathic thrombocytopenic purpura, is the most common hematologic bleeding disorder, which is caused by the dysfunction of the immune system resulting in the production of antibodies and lymphocytes against self platelets, which destroy platelets and lead to shortened platelet life span, accompanied by poor bone marrow compensatory platelet production, eventually leading to peripheral blood When the number of platelets in the circulation decreases to a certain extent, bleeding can occur, ranging from bleeding in the skin and mucous membranes (purpura and petechiae) to bleeding in the internal organs and even death due to intracranial hemorrhage in severe cases. The annual incidence of ITP is about 38 per 1 million population. The cause of the disease is still unclear, and factors associated with its development include infectious (especially viral) factors, genetic factors, and the action of estrogen. The author believes that patients with this disease have abnormal immune function associated with genetic factors and have the basis of autoimmune disease. In cases such as infections where the body’s immune system needs to be mobilized to defend against and destroy foreign invaders, this autoimmune function against their own platelets is also mobilized, thus causing the destruction of platelets, and this destruction mechanism becomes more active in the presence of increased estrogen, such as in female pregnancy. (ii) Clinical manifestations: When platelets fall below a certain level (<30×109/L), bleeding signs will appear, and when the platelet count is <10×109/L or even <5×109/L, there will be severe bleeding manifestations. Clinical bleeding manifestations are mainly skin and mucous membrane bleeding such as subcutaneous bleeding spots, purpura, petechiae, nasal bleeding, gum bleeding, etc. In severe cases, there can be oral blood blisters and hematuria. Female patients may have increased menstruation as the only manifestation. Severe thrombocytopenia can lead to death due to intracranial hemorrhage. Patients with ITP usually do not have splenomegaly, and splenomegaly often has another cause. (iii) Diagnosis and treatment: The doctor will initially consider the diagnosis of ITP in the context of the patient's bleeding manifestations and routine blood tests showing "only thrombocytopenia with normal hemoglobin and white blood cell counts", and will then mobilize the patient to undergo bone marrow aspiration, abdominal ultrasound, antinuclear antibody profile, immunoglobulin quantification, rheumatoid factors, viral indicators, and pylorus. Afterwards, the doctor will ask the patient to undergo a number of tests such as bone marrow aspiration, abdominal ultrasound, antinuclear antibody profile, immunoglobulin quantification, rheumatoid factor, viral indicators, H. pylori test, etc. to confirm the diagnosis, exclude related diseases, clarify the presence of underlying diseases (such as SLE and other autoimmune diseases) and infection triggers. Once the diagnosis is established, treatment can be started. When the patient's platelet count is ≥30×109/L, there is often no obvious bleeding manifestation, so such patients can be followed up for observation and health education on related knowledge. When the patient has obvious bleeding symptoms and the platelet count is <10×109/L or even <5×109/L, the doctor will take emergency treatment measures such as giving higher doses of glucocorticoids (hormones) and high doses of intravenous gammaglobulin combined with platelet infusion in order to raise the platelet count to a safe level quickly, and then transition to conventional treatment. The doctor will calculate the initial dose of prednisone (a hormone) based on the patient's body weight at 1 mg per kilogram of body weight and instruct the patient to take it orally daily and gradually reduce the dose after 3 weeks until it is discontinued, with the goal of maintaining a platelet count of ≥30×109/L without bleeding manifestations. If these criteria are not met, second-line treatment options are considered including splenectomy, immunosuppressants such as vincristine, danazol, cyclosporine A (CsA), thrombopoietin (TPO), anti-CD20 monoclonal antibodies (melphalan), and certain herbal medicines. For certain refractory cases, evidence of potential triggers such as viral infections (hepatitis C virus, hepatitis B virus, HIV, EBV, etc.) and Helicobacter pylori infection should be actively sought. Once these triggers are found and eradicated or controlled, platelet counts can often be restored. (iv) Prevention: To prevent infection, one should enhance physical fitness, pay attention to personal hygiene and dietary sanitation, increase and decrease clothing according to weather changes, change poor lifestyle habits, and eliminate drug use and unsafe sex. Pregnancy can be a predisposing factor for ITP and is often aggravated during pregnancy in patients with pre-existing ITP, so monitoring platelet counts during pregnancy is essential. Patients diagnosed with ITP should be absolutely bedridden, avoid mood swings, and keep blood pressure stable and in a safe range when platelet count is extremely low (<10×109/L) and bleeding tendency is present. Patients with ITP are often aggravated by infection, so in addition to measures to prevent infection, once infection occurs, platelet count should be monitored for timely detection and treatment.