post-transfusion thrombocytopenic purpura
Introduction
Introduction to thrombocytopenic purpura after transfusion Post-transfusion thrombocytopenic purpura (PTTP), also known as "purine after transfusion", acute, immunological, transient thrombocytopenia and bleeding symptoms occurring 7 to 10 days after transfusion. basic knowledge The proportion of illness: 0.0065% Susceptible people: no special people Mode of infection: non-infectious Complications: intracranial hemorrhage
Cause
Thrombocytopenic purpura after transfusion
(1) Causes of the disease
Alloimmunity produced by human platelet antigen (HPA) can cause the disease.
(two) pathogenesis
Most of the disease is caused by the same antibody against HPA-1a antigen. When HPA-1a-positive platelets are delivered to HPA-1b, anti-HPA-1a antibody is produced in the patient 7 to 10 days after transfusion. If the pregnant woman's platelet HPA-1a antigen is negative, her husband's platelet HPA-1a antigen is positive, the antigen can sensitize pregnant women through the placenta, when the patient receives HPA-1a antigen-positive platelets again, the body anti-HPA-1a The antibody can bind to the donor platelet HPA-1a antigen, resulting in destruction of the donor platelet, release of the immune complex when the platelet is destroyed, and binding to the platelet Fc receptor, resulting in non-specific immune damage to the autologous platelets, anti-HPA- The level of 1a antibody titer is often proportional to the severity of clinical manifestations.
HPA-1a/b is located in platelet membrane glycoprotein IIIa, allele is Leu33/Pro33, and HPA-1a antigen-positive patients have thrombocytopenia after transfusion, which may be related to other platelet antigens such as HPA-5a, in addition, anti-HLA antibody It can also cause the disease to occur.
In addition, some female patients have no history of pregnancy or blood transfusion, and there is no history of blood transfusion in male patients. The pathogenesis of these patients is unknown.
Prevention
Thrombocytopenic purpura prevention after transfusion
Avoid transfusion of platelets and blood products containing platelets as much as possible.
Complication
Thrombocytopenic purpura complications after transfusion Complications intracranial hemorrhage
The main complication is intracranial hemorrhage, but it is rare, sometimes the disease is very dangerous and can be life-threatening. Clinical statistics show that 10% of deaths due to bleeding,
Symptom
Thrombocytopenic purpura symptoms after transfusion Common symptoms Difficulty breathing High fever chills Chest pain Cold war Blood vesicle Hematuria Thrombocytopenia
After entering the blood products containing platelets, the disease occurs 7 to 10 days, and there are obvious symptoms of immune reaction, such as chills, chills, high fever, urticaria, severe headache, chest pain, difficulty breathing or even shock, and then the platelets are obviously reduced acutely. Different degrees of bleeding, skin spots, ecchymosis, oral cavity, nasal bleeding, blood blistering of the tongue mucosa, severe cases may have hematuria, gastrointestinal bleeding or vaginal bleeding.
Examine
Examination of thrombocytopenic purpura after transfusion
1. The peripheral platelets are severely reduced. The number of platelets in the first hemorrhage is very low, often less than 10×109/L, and the bleeding time is prolonged.
2. Anti-HPA-1a antibody can be detected in most cases. This antibody is of IgG type and lasts for 12 to 15 months.
3. Bone marrow examination showed that nucleated cells proliferated, the number of megakaryocytes was normal or increased, and the red granules did not change significantly.
According to the condition, clinical manifestations, symptoms, signs, choose ECG, B-ultrasound, X-ray, MRI, CT, biochemistry, etc.
Diagnosis
Diagnosis and differentiation of thrombocytopenic purpura after transfusion
Diagnosis can be based on medical history, clinical manifestations, and laboratory tests.
