Idiopathic thrombocytopenic purpura

Introduction to primary thrombocytopenic purpura Primary thrombocytopenic purpura refers to thrombocytopenia caused by no obvious exogenous causes, but most of them are due to increased platelet destruction caused by immune response, so it is also known as autoimmune thrombocytopenia, which is a common type of hemorrhagic disease. Hematological diseases are characterized by shortened platelet life and increased megakaryocytes in bone marrow. In 80%-90% of cases, there are IgG antibodies on the surface of serum or platelets, and the spleen has no obvious swelling. According to the pathogenesis, predisposing factors and course of disease, ITP is divided into acute and chronic types. 80% of children are acute (AITP), no gender difference, easy to develop in spring and winter. Once the source is cleared, the disease will heal in June-December, and the adult ITP is more than 95% chronic (CITP). The ratio of male to female is about 1 : 3, generally considered to be a kind of autoimmune disease, prolonged and difficult to heal. The mortality rate of this disease is about 1%, most of them are due to intracranial hemorrhage. The main clinical manifestations of ITP are skin mucosal hemorrhage or visceral hemorrhage. basic knowledge The proportion of illness: 0.01 Susceptible people: no special people Mode of infection: non-infectious Complications: blood in the stool, intracranial hemorrhage, coma

Primary thrombocytopenic purpura

1. Acute type ITP occurs in the recovery period of viral infection or upper respiratory tract infection, such as rubella, measles, chickenpox, salivary gland cancer, etc., patients have higher antiviral antibodies in serum, and platelet surface related antibodies are significantly increased, so it is considered to be The pathogenesis of viral antigens may be that antigen-antibody complexes including viral antigens and platelet fc receptors or autoantibodies produced by viral antigens cross-react with platelet membranes, damage platelets, and are cleared by phagocytic cells.

2. There is no history of prodromal infection before the onset of chronic ITP. It is caused by autoantibodies caused by changes in platelet structure antigens. 80% to 90% of the patients have platelet surface-related antibodies, 95% of which are PalgG, 2/3 of PalgG and PalgM. A few effects are PalgA and pac. The antibody acts directly on the glycoprotein on the platelet membrane. A small number of effects and Gbib complex cause shortening of platelet life and functional changes. The content of the platelet is negatively correlated with platelet life. It has been confirmed that the spleen is a platelet antibody production. The main place.

Primary thrombocytopenic purpura prevention

1. Actively participate in sports activities to enhance physical fitness and improve disease resistance.

2. Pay attention to prevent respiratory infections, measles, chickenpox, rubella and hepatitis, otherwise it is easy to induce or aggravate the condition.

3. In the acute phase or when there is a lot of bleeding, rest in bed, limit the activities of children, and eliminate their fear and nervousness.

4. Avoid traumatic collisions, so as not to cause bleeding.

5. When the platelet count is lower than 20×10 ⁹ /L, it is necessary to closely observe the changes in the condition and prevent various trauma and intracranial hemorrhage.

6. Diet should be light, nutritious, easy to digest, hematemesis, blood in the stool should be in a semi-flow diet, avoid hard food and crude fiber food, avoid spicy food, children can eat more peanuts, red dates and other foods .

Primary thrombocytopenic purpura complications Complications, blood in the stool, intracranial hemorrhage

Severe patients may have hematemesis and blood in the stool. Very few patients may have intracranial hemorrhage, intracranial hypertension, and even coma.

Symptoms of primary thrombocytopenic purpura Common symptoms thrombocytopenia platelet life shortens skin purpura skin sputum chills splenomegaly bloody physique

(a) symptoms

1, acute type

It is common in children, accounting for 90% of the patients with immune thrombocytopenia. The incidence rate is similar between men and women. 84% of patients have a history of respiratory or other viral infections 1 to 3 weeks before onset. Therefore, the incidence is the most in autumn and winter, and the onset is rapid. , chills, skin and mucous purpura, such as patients with headache, vomiting, should be alert to the possibility of intracranial hemorrhage, the course of disease is mostly self-limiting, more than 80% can be self-relieved, the average course of disease 4 to 6 weeks, a few can be prolonged or more than a few years For chronic, acute type accounts for less than 10% of adult ITP.

2, chronic type

Common in young women, women are 3 to 4 times more likely to be male, the onset is concealed, the symptoms are mild, bleeding often recurrent, each bleeding lasts for several days to several months, the degree of bleeding is related to platelet count, platelets > 50 × 10 ⁹ /L, often post-injury hemorrhage; platelets between (10 ~ 50) × 10 ⁹ / L may have different degrees of spontaneous bleeding, platelets less than 10 × 109 / L often have severe bleeding, patients with general symptoms except bleeding symptoms good.

(two) signs

1, acute type

Sudden occurrence of extensive and serious skin and mucous purpura, even large ecchymoses and hematoma, skin defects are mostly systemic, the lower limbs are more, evenly distributed, bleeding is more common in the nose, gums, oral cavity may have blood, gastrointestinal tract And urinary tract bleeding is not uncommon, intracranial hemorrhage is rare, but what is the risk, the spleen often does not enlarge.

2, chronic type

Skin purpura is more common in the distal extremities of the lower extremities. Hemorrhage is more common in the nose, gums, and oral mucosal hemorrhage. Female menstruation is sometimes the only symptom. Repeated episodes can cause anemia and mild splenomegaly. If there is obvious splenomegaly, To exclude the possibility of secondary platelets.

Examination of primary thrombocytopenic purpura

1. Blood: generally no anemia (severe bleeding may have mild anemia), white blood cell count is normal, platelet count is reduced.

2. Coagulation examination: prolonged bleeding time; clotting time, prothrombin time, thrombin time are normal.

3. Bone marrow: normal hyperplasia, increased number of megakaryocytes, with maturity disorders (most patients produce platelet-type megakaryocytes <30%).

4. Autoantibody examination: platelet surface related antibodies (PAIgG) increased significantly; platelet surface related C3 (PA C3) increased.

5. Determination of platelet life: significantly shortened.

Diagnosis and diagnosis of primary thrombocytopenic purpura

Diagnostic criteria

Acute ITP platelets are significantly reduced, usually less than 20 × 10 ⁹ / L, platelet life is significantly shortened, about 1 to 6 hours, bone marrow examination, most of the medical records of megakaryocytes increased or normal, of which immature megakaryocytes increased significantly, chronic ITP more test thrombocytopenia Mostly (30 ~ 80) × 10 ⁹ / L, bone marrow megakaryocytes mostly increased, the size is basically normal, the granule type increased, platelet formation decreased significantly, platelet surface related IgG increased, platelet-related C3 increased, platelet life shortened, about 1 ~3 days, the diagnostic criteria are as follows:

1, multiple tests to check the reduction of platelet count.

2. The spleen does not increase or only slightly increases.

3, bone marrow examination megakaryocyte number increased or normal, there are maturity disorders.

4. The following five points should have any point:

(1) Prednisone treatment is effective.

(2) effective spleen treatment

(3) Increase in PalgG.

(4) Increased PAC, shortened platelet life, and exclusion of secondary thrombocytopenia.

Differential diagnosis

It is necessary to rule out thrombocytopenia caused by acute leukemia, lymphoma, thrombotic thrombocytopenic purpura, autoimmune diseases, Evans syndrome and drugs.

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