The spleen we are talking about here is not the same thing as the “spleen” often mentioned in TCM. Although the spleen is one of the five organs in traditional Chinese medicine, it is not a substantial organ – it is not found in the body. This is what we often hear about “weakness of the spleen and stomach” and “disharmony of the spleen and stomach”. When discussing the spleen, it is necessary to exclude the concepts in Chinese medical theory to avoid misunderstanding. So what exactly is the spleen? And what is hypersplenism?
Overview
Unlike hollow organs like the stomach, intestines, and bladder, the spleen is a substantial organ – a whole structure shaped like a large pea, slightly smaller than one’s own hand fist in its normal state, occupying the left and right sides of the upper abdominal cavity roughly symmetrically with the liver, protected by the rib cage. The spleen is an important lymphatic organ, but is not on the lymphatic tract system, but on the blood tract. It has functions such as hematopoiesis, blood filtration, removal of senescent blood cells and participation in the immune response. When hypersplenism occurs, the main clinical manifestations are related to its function of removing blood cells.
Hypersplenism, referred to as hypersplenism, refers to a clinical syndrome accompanied by splenomegaly and excessive consumption of blood cells due to various causes. Hypersplenism is a syndrome and is not a diagnostic name for an independent disease. Blood cells and platelets are destroyed during filtration in the overly enlarged spleen, resulting in corresponding clinical manifestations such as anemia, granulocytopenia, thrombocytopenia, and active bone marrow hematopoiesis.
Pathogenesis
Primary splenomegaly is rare, and no clear etiology is recognized to date. It often leads to primary granulocytopenia, primary thrombocytopenia, etc. In addition, aneurysms and cavernous hemangiomas of the spleen itself can cause some degree of hyperfunction.
The vast majority of hypersplenism is secondary, meaning that it is not the spleen itself that is diseased. The main causes include
1. Stasis splenomegaly due to portal hypertension, which is by far the most common type of hypersplenism in clinical practice. Portal hypertension is also a clinical syndrome secondary to various causes of cirrhosis. Viral hepatitis, alcoholic liver injury, liver fluke or schistosomiasis, autoimmune hepatitis, Buga syndrome, portal vein thrombosis or cavernous vascular degeneration are some of the more common causes.
2, chronic hemolytic diseases such as hereditary spherocytosis, autoimmune hemolysis and maritime anemia;
3, various infections accompanied by splenomegaly, acute infections are common in viral hepatitis or infectious mononucleosis, chronic infections are mostly seen in tuberculosis, brucellosis, malaria, schistosomiasis, hepatic schistosomiasis, etc.;
4, various immune system diseases, inflammatory granulomas, such as systemic lupus erythematosus, rheumatoid arthritis, Felty’s syndrome and nodular disease, etc;
5, malignant tumors such as lymphoma, leukemia and metastatic splenic tumors;
7, hereditary lipid deposition disorders, such as Gaucher disease and Niemann-Pick disease;
8, myeloproliferative disorders such as true erythroblastosis, chronic granulocytic leukemia and myelofibrosis, etc.
Symptoms and hazards
The main danger of hypersplenism is in two aspects. Firstly, the dominant effect of splenomegaly can cause a certain degree of discomfort, mainly in the form of abdominal distention and a feeling of fullness after eating. However, this is often tolerated by the patient, and it is possible to see patients with a “giant spleen”, where the entire left side of the abdomen is occupied by the spleen.
The physiological effects are mainly related to the function of the spleen, as the blood passes through it, destroying excessive blood cells and causing a decrease in red blood cell, white blood cell and platelet counts, with a series of symptoms. In short, a decrease in granulocytes, which can cause infections, a decrease in red blood cells, or anemia, can result in pallor and weakness, and a decrease in platelets, which can cause bleeding.
In hypersplenism, if accompanied by bone marrow suppression, hematopoiesis may be enhanced, and immune and secretory functions may be affected. However, the relative decrease in blood cell count is often easily overlooked.
Ancillary tests
Many cases of hypersplenism are insidious, i.e., the clinical manifestations may not be obvious due to compensatory bone marrow hyperplasia, which compensates to some extent for the depletion of blood cells. The diagnosis of hypersplenism is commonly made by abdominal ultrasound (or CT) combined with routine blood tests suggesting an increase in spleen size along with a decrease in blood cell and/or platelet counts. It is important to note that there are often physical examination results that indicate an “enlarged spleen”, which is a physician’s judgment based on the average for a normal person and does not necessarily indicate hypersplenism, but requires a clinical diagnosis. In addition, ECT, PET-CT, and pathological biopsy are all possible diagnostic options. However, the most important thing in the diagnosis of hypersplenism is to identify the primary cause of the disease in order to provide targeted treatment.
Treatment modalities and indications
For secondary hypersplenism, aggressive treatment is required for the primary cause. For example, if the infection is controlled, the leukemia is in remission, and the portal hypertension is reduced, most hypersplenism can be relieved to some extent. However, in the case of splenomegaly that remains uncontrollable after non-surgical treatment, surgical or interventional treatment is the preferred modality because there are no specific drugs that can contain it once it causes severe anemia, thrombocytopenia leading to severe bleeding, etc. It generally includes splenectomy, partial splenectomy, interventional treatment (currently, splenic artery embolization is the main treatment), etc. Among them, splenectomy has the most direct and definite efficacy. Except for primary hypersplenism and splenic diseases such as splenic tumors, splenectomy for hypersplenism needs to meet strict indications. The main diseases include the following.
1. congestive splenomegaly due to portal hypertension;
2. Infectious diseases causing splenomegaly, such as splenic abscess, tuberculosis;
3, hereditary spherocytosis, autoimmune hemolytic anemia, etc.;
4.Primary thrombocytopenic purpura with ineffective medical treatment;
5, chronic aplastic anemia;
6.Chronic granulocytic leukemia causing giant spleen;
7.Goser’s disease;
8, certain Hodgkin’s disease.
It should be especially emphasized that splenectomy or splenic artery embolization can only relieve the effect of the spleen on the hematological system and cannot cure the original disease. In particular, some hematologic diseases such as hypersplenism in erythroleukemia have a remitting effect on the symptoms of the disease itself, patients with chronic myelofibrosis in which hematopoiesis can be transferred to the spleen during myelosclerosis, or Gaucher’s disease in which liver lesions may be aggravated after removal of the spleen, removal of the spleen may do more harm than good.
For patients who are suitable for spleen removal, the feasibility of their own conditions and whether they have contraindications to surgery also need to be evaluated in a regular hospital specialty. If surgical treatment is not tolerated, interventional treatment through less invasive procedures is not an inappropriate option.
Treatment and prevention of the disease
Although hypersplenism is detrimental to health, its effects are limited. Except in severe cases where life is endangered by outbreaks of infection and blood tendency, the prognosis of most hypersplenic patients is often directly related to the primary disease. Given the diversity and complexity of the primary disease, prevention is almost impossible. Considering the high prevalence of viral hepatitis in China, prevention of hepatitis transmission and aggressive antiviral therapy are still relevant.
For hypersplenism of other etiologies, the choice of treatment needs to be made with full reference to the professional opinions of hematology, rheumatology and infection departments, and the impact of spleen removal should be fully evaluated before deciding whether to perform surgical treatment.