Hypersplenism
Introduction
Introduction to hypersplenism Hypersplenism, referred to as splenomegaly, is a syndrome. Many diseases can cause hypersplenism. Among them, cirrhosis caused by various causes is the most common, such as cirrhosis after hepatitis, schistosomiasis. Liver cirrhosis, portal cirrhosis, etc.; followed by chronic infections, such as malaria; and the hereditary spherocytosis in the blood system, autoimmune anemia, primary thrombocytopenic purpura and other diseases Causes hypersplenism. The clinical manifestations are splenomegaly, one or more blood cells are reduced, and the bone marrow hematopoietic cells are correspondingly hyperplasia, the blood image is restored after splenectomy, and the symptoms are relieved. basic knowledge The proportion of sickness: 0.01% Susceptible people: no special people Mode of infection: non-infectious Complications: anemia
Cause
Causes of hypersplenism
Primary splenomegaly (25%):
Primary person refers to a series of manifestations that the underlying disease has not been determined, but clinically has hypersplenism. There are so-called primary spleen hyperplasia, non-tropical idiopathic splenomegaly, primary splenic granulocyte reduction, primary spleen whole blood cell reduction, splenic anemia or splenic thrombocytopenia. Because the cause is unknown, it is difficult to determine whether the disease is a different cause of the same cause or an independent disease that is not related to each other.
Secondary splenomegaly (30%)
Secondary is defined as a disease other than the spleen that affects the spleen, leading to hypersplenism, and most of the primary diseases have been diagnosed. More clinically seen secondary hypersplenism, including those with more obvious causes: (1) acute infection with splenomegaly: such as viral hepatitis or infectious mononucleosis. (2) Chronic infections: such as tuberculosis, brucellosis, malaria, etc. (3) Congestive splenomegaly: portal hypertension: intrahepatic obstructive (such as portal cirrhosis, necrotizing cirrhosis, biliary cirrhosis, hemosiderosis, sarcoidosis, etc.) and extrahepatic Obstructive (external compression or thrombosis of the portal vein or splenic vein). (4) Inflammatory granuloma such as systemic lupus erythematosus, rheumatoid arthritis, Felty syndrome and sarcoidosis. (5) Malignant tumors such as lymphoma, leukemia and cancer metastasis. (6) Chronic hemolytic diseases such as hereditary spherocytosis, autoimmune hemolytic anemia, and marine anemia. (7) Lipid-like deposits such as Gaucher disease and Niemann-Pick disease. (8) Myeloproliferative disorders such as polycythemia vera, chronic myeloid leukemia and myelofibrosis. (9) Others: such as splenic aneurysms and cavernous hemangioma.
Occult spleen (30%):
Regardless of primary or secondary splenomegaly, because the bone marrow compensatory hyperplasia is good, the peripheral blood picture does not show blood cell reduction, but once infected or drugs and other factors inhibit hematopoietic function, it can lead to single or whole blood cell cytoreduction.
Pathogenesis
Although the pathogenesis of hypersplenism still needs further investigation, according to the physiological functions of the spleen, there are several theories:
1. Excessive retention The blood vessels in the spleen are rich and the structure is special. The blood cells stay in the sinusoids and spleen for a long time. The sinus cells and macrophages in the red pulp are well recognized by the blood cells filtered by them. Retention performance. Under normal circumstances, most of the blood cells that are blocked are senescent, congenital morphological abnormalities, abnormal hemoglobin structure, cells damaged by oxidized substances or encapsulated by antibodies, these blood cells usually remain in the spleen and suffer damage. There is no red blood cell or white blood cell storage in the normal spleen, but about 1/3 of the platelets and some lymphocytes are blocked in the spleen. When the spleen has a pathologically significant enlargement, not only more platelets (50% to 90%) and lymphocytes are retained in the spleen, but also more than 30% of red blood cells are retained in the spleen, resulting in platelets in the surrounding blood. And red blood cells are reduced.
2, excessive screening and phagocytosis of the spleen spleen mononuclear-macrophage system is overactive, while abnormal erythrocytes in the spleen cord (such as spherical cells and red blood cells damaged by antibodies, oxidants or other chemical poisons, physical factors, etc.) Increased and cleared for macrophages, resulting in a significant reduction in red blood cells in the surrounding blood. Some of the erythrocyte membranes have hydantoplasts, or there are gluten-like bodies in the syrup, and even the trophozoites of the malaria parasite; when the spleen enters the sinus, the common red blood cells are due to the hydantosome or the genus Being trapped in the sinus basement membrane hole and dilemma, and finally excavated for the sinus wall macrophage, and the erythrocyte membrane was damaged. After repeated damage, the red blood cells become spherical cells and eventually cannot be swallowed through the pores of the basement membrane.
3, body fluid factors Some scholars have suggested that the spleen can produce certain secretin to inhibit the formation and maturation of bone marrow blood cells, and also inhibit the release of mature blood cells in the bone marrow. Once the inhibitory factor is removed, the abnormal performance of bone marrow cells quickly returns to normal. It has been proved that: 1 spleen extract can be injected into animals, which can reduce blood cells; 2 patients with spleen after the increased tolerance to radiation therapy and chemotherapy, may be the result of removal of body fluid factors.
4. Immune factors It is considered that hypersplenism is a type of autoimmune disease. The spleen can produce antibodies, destroying its own blood cells, and reducing the surrounding blood cells, and the bone marrow has compensatory hyperplasia. For example, immune thrombocytopenic purpura and autoimmune hemolytic anemia, the spleen is considered to be the main site for the production of antibodies, and is also the place to destroy blood cells; when the spleen is removed, the blood and bone marrow tend to improve.
5. Dilution When the spleen is swollen, the total plasma volume is also significantly increased, which can dilute the blood and cause blood cells to decrease. Anemia is the result of the double action of pseudo-anemia caused by the retention and dilution of the spleen on blood cells. A large spleen can correct the dilute anemia and restore normal plasma volume.
Prevention
Prevention of hypersplenism
Actively prevent cirrhosis caused by various causes (especially schistosomiasis cirrhosis), chronic infections such as malaria, tuberculosis, malignant tumors such as lymphoma, chronic lymphocytic leukemia, myelofibrosis and chronic hemolytic anemia and rare nets Endothelial cell disease.
Complication
Complications of hypersplenism Complications anemia
1, spleen embolism, inflammation around the spleen, visible left upper abdomen or left lower chest pain, and with the increase in breathing, local tenderness and friction, can be heard and rubbing sound.
2, combined with various infections, the main reason is the reduction of white blood cells.
3. When the blood passes through the spleen, the blood cells are excessively damaged, resulting in a decrease in the count of red blood cells, white blood cells and platelets, accompanied by a series of symptoms. In short, neutropenia, easy to cause infection, red blood cell reduction, that is, anemia, there will be pale, weak and weak performance, thrombocytopenia is likely to cause bleeding.
4. In the case of hypersplenism, if accompanied by myelosuppression, hematopoietic function may be enhanced, and immune and secretory functions may also be affected. However, relative blood cell counts are reduced and are often overlooked.
Symptom
Symptoms of hypersplenism Symptoms Common symptoms erythrocytosis portal hypertension dizziness venous thrombosis thrombocytopenia palpitations supraoptic vertical eye muscle tendon bleeding tendency whole blood cell reduction splenomegaly
(A) primary hypersplenism: the cause is unknown, such as primary spleen hyperplasia, non-tropical idiopathic splenomegaly, primary splenic granulocyte reduction, primary spleen whole blood cell reduction, spleen anemia or Spleen thrombocytopenia and the like.
(B) secondary splenomegaly: the cause is clearer, common causes are: infection (such as viral hepatitis, infectious mononucleosis, malaria, etc.), portal hypertension (such as cirrhosis, hemosiderin Septicosis, sarcoidosis, portal vein thrombosis, etc.), inflammatory granuloma (such as systemic lupus erythematosus, rheumatoid arthritis, Felty syndrome and sarcoidosis), malignant tumors (such as lymphoma, leukemia and cancer) Swelling metastasis, etc., chronic hemolytic disease (such as hereditary spherocytosis, autoimmune hemolytic anemia and marine anemia), lipidoidosis (such as Gaucher disease and Niemann-Pick disease), bone marrow Hyperplasia (such as polycythemia vera, chronic myeloid leukemia and myelofibrosis).
(C) occult spleen hyperthyroidism: no matter the primary, or secondary spleen hyperfunction, when the bone marrow compensatory hyperplasia is good, the surrounding blood picture may not show blood cell reduction, the symptoms of hypersplenism are hidden, but once When an infection, or drug, inhibits hematopoietic function, the patient will have a single or complete cytopenia.
Clinical manifestations:
Symptoms vary in severity, mild condition, even asymptomatic, secondary hypersplenism, often accompanied by symptoms of primary disease, and even cover up the symptoms of hypersplenism itself, the patient's resistance is reduced, pale, head Fainting, palpitations, easy infection, fever, thrombocytosis when there is a tendency to hemorrhage, physical examination, spleen can be mild, moderate and severe swelling.
Examine
Examination of hypersplenism
(1) Ultrasound examination: In most cases, the spleen is swollen, but the degree of spleen enlargement is not necessarily proportional to the degree of hypersplenism.
For those who do not touch the spleen under the ribs, further examination should be carried out to confirm whether the swelling is large. The spleen area scan after 99m , 198 gold or 113m indium colloid injection is helpful to estimate the size and shape of the spleen. Computerized tomography scan The spleen size and spleen lesions can also be measured.
(B) peripheral blood examination: peripheral blood red blood cells, white blood cells or platelets can be reduced alone or simultaneously, in general early cases, only white blood cells or thrombocytopenia, advanced cases of whole blood cell reduction, blood cell reduction is not proportional to spleen enlargement.
(3) Bone marrow puncture: The bone marrow is a hematopoietic cell hyperplasia. In some cases, maturity disorders may also occur at the same time. It may also be due to the massive destruction of peripheral blood cells and the excessive release of mature cells, resulting in similar maturity disorders.
(IV) Radionuclide scanning: 51Cr-labeled platelets or red blood cells were injected into the body and scanned on the body surface. It was found that the amount of 51Cr in the spleen area was 2 to 3 times larger than that in the liver, suggesting that platelets or red blood cells were destroyed excessively in the spleen.
(5) Changes in splenectomy: After splenectomy, the number of blood cells can be brought close to or return to normal unless the bone marrow hematopoietic function has been impaired.
Diagnosis
Diagnosis and differentiation of hypersplenism
Diagnosing hypersplenism depends on the following indicators:
(1) Spleen enlargement: In most cases, the spleen is swollen. For those who have not touched the spleen under the rib, further examination should be carried out to confirm whether it is swollen. Apply spleen after injection of 99m , 198 gold or 113m indium colloid. Area scans help to estimate the size and shape of the spleen. Computerized tomography can also measure spleen size and spleen lesions, but the degree of splenomegaly is not necessarily proportional to the degree of hypersplenism.
(B) blood cell reduction: red blood cells, white blood cells or platelets can be reduced alone or simultaneously, in general early cases, only white blood cells or thrombocytopenia, complete cases of complete blood cell reduction in advanced cases.
(3) Bone marrow is a hematopoietic cell hyperplasia: some cases may also have maturity disorders at the same time, or a large number of peripheral blood cells may be destroyed, and mature cells are released too much, causing similar maturity disorders.
(D) changes in splenectomy: after splenectomy can make the number of blood cells close to or return to normal, unless the bone marrow hematopoietic function has been damaged.
(5) Radionuclide scanning: 51Cr-labeled platelets or red blood cells were injected into the body and scanned on the body surface. It was found that the amount of 51Cr in the spleen area was 2 to 3 times larger than that in the liver, suggesting that platelets or red blood cells were destroyed excessively in the spleen.
When considering the diagnosis of spleen, the previous three are particularly important.
The bone marrow of this disease is a hematopoietic cell hyperplasia. In some cases, there may be maturity disorders at the same time. It may also be due to the destruction of a large number of peripheral blood cells, and the release of mature cells is too much, resulting in similar maturity disorders, so it is necessary to pay attention to distinguish them.
