Auntie Zhang has recently encountered a troubling problem. She thought it was due to her age, but a week ago she felt a hard object in her abdomen, which made her panic: could it be a tumor? She rushed to our hospital for consultation. After some examination, I found that Auntie Zhang was severely anemic, which was caused by “enlarged spleen and hypersplenism”. Auntie Zhang was puzzled: she is recognized as a good temper, how come her spleen is enlarged? In fact, the size of the spleen has nothing to do with “temper”. The spleen is located in the upper left abdomen and is “suspended” by several ligaments in the front and back of the abdominal wall, adjacent to the stomach, pancreas, left kidney and colon. The spleen is the largest immune organ in the body, accounting for 25% of the total lymphoid tissue, and is the center of cellular and humoral immunity in the body. It produces immunoglobulins, complement and other immune substances and plays an immune role. The spleen is also the “filter” of the blood circulation. When there are germs, antigens, foreign bodies, protozoa and dead cells in the blood, especially red blood cells and platelets, the macrophages and lymphocytes in the spleen will “eat” them up. The spleen is also the “blood bank” of the body. It stores blood when the body is at rest and quiet; when the body is under stress such as exercise, blood loss, or lack of oxygen, it drains blood into the circulation to increase circulating blood volume. The adult spleen is roughly the size of one’s fist and weighs about 200 grams. The spleen is usually not palpable in the normal state. If the spleen is palpable in the supine or right lateral position, the spleen is enlarged. At this time, the spleen is at least twice as large. The enlarged spleen can be detected earlier by ultrasonography than by hand. What conditions can cause an enlarged spleen? There are many causes of an enlarged spleen. Among them, only a few are physiological enlargement. Most people who find an enlarged spleen should look for the cause under the guidance of a doctor and should be reviewed regularly. The main causes of splenomegaly are: (1) infectious splenomegaly, various acute and chronic infections such as typhoid fever, paratyphoid fever, black fever, malaria, sepsis, late syphilis, etc.; (2) congestive splenomegaly, cirrhotic portal hypertension, chronic heart failure leading to cardiogenic cirrhosis, chronic constrictive pericarditis, portal vein or splenic vein thrombosis, and Bentia’s syndrome, etc., which may lead to splenomegaly and (3) proliferative splenomegaly, which is seen in certain hematological diseases such as leukemia, hemolytic anemia, malignant lymphoma, thrombocytopenic purpura, etc.; (4) other rare causes such as primary tumors of the spleen, cysts, disseminated lupus erythematosus, dermatomyositis, polyarteritis nodosa, Gaucher’s disease, etc. In the middle and lower reaches of Yangtze River, the more common causes of splenomegaly are cirrhosis secondary to viral hepatitis or schistosomiasis, and portal hypertension. III. What are the consequences of an enlarged spleen? As I said earlier, the spleen is the “filter” of blood circulation. This is because there are many structures called “blood sinuses” in the spleen tissue, and the walls of the sinuses have a large number of macrophages attached to them, which are able to swallow aging red blood cells, platelets and other “dirty things”. When the spleen is enlarged, the blood sinusoids increase, and their phagocytic and destructive effects on blood cells are enhanced. Patients may experience anemia, thrombocytopenia and even leukopenia. In addition, if the patient suffers from trauma such as bruises on the abdomen, it is very easy to cause spleen rupture and fatal hemorrhage. 4. How to know the enlarged spleen early? Under normal circumstances, the spleen is usually not palpable. If the edge of the spleen can be felt in the supine or lateral position, the spleen should be considered enlarged. In some people with a low diaphragm or a thin body, especially women, the edge of the spleen can occasionally be felt, but it is quite soft and without pressure, unlike pathological splenomegaly. Patients with splenomegaly usually have some of the following symptoms, such as anemia, bleeding spots or petechiae; edema and ascites; anorexia and abdominal distention. Top: Imaging of the spleen in a normal person Bottom: Imaging of an enlarged spleen