Author/s: Teresa G. Norris

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Definition
Hypersplenism is a type of disorder which causes the spleen to rapidly and prematurely destroy blood cells.

Description
The spleen is located in the upper left area of the abdomen. One of this organ's major functions is to remove blood cells from the body's bloodstream. In hypersplenism, its normal function accelerates, and it begins to automatically remove cells that may still be normal in function. Sometimes, the spleen will temporarily hold onto up to 90% of the body's platelets and 45% of the red blood cells. Hypersplenism may occur as a primary disease, leading to other complications, or as a secondary disease, resulting from an underlying disease or disorder. Hypersplenism is sometimes referred to as enlarged spleen (splenomegaly). An enlarged spleen is one of the symptoms of hypersplenism. What differentiates hypersplenism is its premature destruction of blood cells.

Causes & symptoms
Hypersplenism may be caused by a variety of disorders. Sometimes, it is brought on by a problem within the spleen itself and is referred to as primary hypersplenism. Secondary hypersplenism results from another disease such as chronic malaria, rheumatoid arthritis, tuberculosis, or polycythemia vera, a blood disorder. Spleen disorders in general are almost always secondary in nature. Hypersplenism may also be caused by tumors.

Symptoms of hypersplenism include easy bruising, easy contracting of bacterial diseases, fever, weakness, heart palpitations, and ulcerations of the mouth, legs and feet. Individuals may also bleed unexpectedly and heavily from the nose or other mucous membranes, and from the gastrointestinal or urinary tracts. Most patients will develop an enlarged spleen, anemia, leukopenia, or abnormally low white blood cell counts, or thrombocytopenia, a deficiency of circulating platelets in the blood. Other symptoms may be presents that reflect the underlying disease that has caused hypersplenism.

An enlarged spleen can be caused by a variety of diseases, including hemolytic anemia, liver cirrhosis, leukemia, malignant lymphoma and other infections and inflammatory diseases. Splenomegaly occurs in about 10% of systemic lupus erythematosus patients. Sometimes, it is caused by recent viral infection, such as mononucleosis. An enlarged spleen may cause pain in the upper left side of the abdomen and a premature feeling of fullness at meals.

Diagnosis
Diagnosis of hypersplenism begins with review of symptoms and patient history, and careful feeling (palpation) of the spleen. Sometimes, a physician can feel an enlarged spleen. X-ray studies, such as ultrasound and computed tomography scan (CT scan), may help diagnose an enlarged spleen and possible underlying causes, such as tumors. Blood tests indicate decreases in white blood cells, red blood cells, or platelets. Another test measures red blood cells in the liver and spleen after injection of a radioactive substance, and indicates areas where the spleen is holding on to large numbers of red cells or is destroying them.

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Enlarged spleens are diagnosed using a combination of patient history, physical examination, including palpation of the spleen, if possible, and diagnostic tests. A history of fever and systemic symptoms may be present because of infection, malaria, or an inflammatory disorder. A complete blood count is taken to check counts of young red blood cells. Liver function tests, CT scans, and ultrasound exams can also help to detect an enlarged spleen.

Treatment
In secondary hypersplenism, the underlying disease must be treated to prevent further sequestration or destruction of blood cells, and possible spleen enlargement. Those therapies will be tried prior to removal of the spleen (splenectomy), which is avoided if possible. In severe cases, the spleen must be removed. Splenectomy will correct the effects of low blood cell concentrations in the blood.

Prognosis
Prognosis depends on the underlying cause and progression of the disease. Left untreated, spleen enlargement can lead to serious complications. Hypersplenism can also lead to complications due to decreased blood cell counts.

Prevention
Some of the underlying causes of hypersplenism or enlarged spleen can be prevented, such as certain forms of anemia and cirrhosis of the liver due to alcohol. In other cases, the hypersplenism may not be preventable, as it is a complication to an underlying disorder.

Key Terms
Cirrhosis
Hardening of an organ, usually the liver. Cirrhosis of the liver is a progressive disease which leads to destruction of liver cells, interference with blood flow in the liver, and interference with the function of the liver.
Palpitations
Throbbing or pulsation. Heart palpitations usually infer an irregular or rapid rhythm.
Polycythemia vera
A chronic disorder characterized by increased red blood cell mass and other malfunctions of the blood system. It most commonly occurs in males of Jewish ancestry between the ages of 40 and 60.
Systemic
Relating to a system, or especially the entire system.
Systemic lupus erythematosus
A connective tissue disease that results in fever, weakness, fatigue, joint pain and arthritis.
Ulcerations
Breaks in skin or mucous membranes that are often accompanied by loss of tissue on the surface.
Further Reading
For Your Information
Books
Conn, Howard F., Robert J. Clohecy, and Rex B. Conn. Current Diagnosis. 9th ed. Philadelphia, PA: WB Saunders Company, 1997.
Organizations
American Liver Foundation. 1425 Pompton Ave., Cedar Grove, NJ 07009. 1-800-GOLIVER (445-4837).
The American Society of Hematology. 1200 19th Street NW, Suite 300, Washington, DC 20036-2422. (202) 857-1118. http://www.hematology.org.
National Heart, Lung and Blood Institute. Building 31, Room 4A21, Bethesda, MD 20892. (301) 496-4236. http://www.nhlbi.nih.gov.
Gale Encyclopedia of Medicine. Gale Research, 1999.

Spleen Disorders

The spleen produces, monitors, stores, and destroys blood cells. It is a spongy, soft, purplish organ about as big as a person's fist and is located in the upper part of the abdominal cavity, just under the rib cage on the left side.

The spleen functions as two organs. The white pulp is part of the infection-fighting (immune) system, and the red pulp removes unwanted material, such as defective red blood cells, from the blood.

Certain white blood cells (lymphocytes) produce protective antibodies and play an important role in fighting infection. Lymphocytes can be produced and reach maturity in the white pulp.

The red pulp contains other white blood cells (phagocytes) that ingest unwanted material, such as bacteria or defective cells, from the circulating blood. The red pulp monitors red blood cells, determines which ones are abnormal or too old or damaged to function properly, and destroys them. Consequently, the red pulp is sometimes called the red blood cell graveyard.

The red pulp also serves as a reservoir for blood elements, especially white blood cells and platelets (cell-like particles involved in clotting). In many animals, the red pulp releases these blood elements into the circulating blood when the body needs them; however, in humans, releasing these elements is not an important function of the spleen.

If the spleen is removed surgically (splenectomy), the body loses some of its ability to produce protective antibodies and to remove unwanted bacteria from the blood. As a result, the body's ability to fight infection is reduced. After a short time, other organs (primarily the liver) increase their infection-fighting ability to compensate for this loss, so the increased risk of infection is not lifelong.

Enlarged Spleen

When the spleen enlarges (splenomegaly), its ability to trap and store blood cells increases. Splenomegaly can reduce the number of red and white blood cells and platelets in the circulation.

Many diseases can make the spleen enlarge. To pinpoint the cause, a doctor must consider disorders ranging from blood cancers to chronic infections.

When the enlarged spleen traps large numbers of abnormal blood cells, the cells clog the spleen, interfering with its functioning. This process can begin a vicious circle: the more cells the spleen traps, the larger it grows; the larger it grows, the more cells it traps.

When the spleen removes too many blood cells from the circulation (hypersplenism), a variety of problems may develop, including anemia (too few red blood cells), frequent infections (because of too few white blood cells), and bleeding problems (because of too few platelets). Eventually, the greatly enlarged spleen also traps normal blood cells, destroying them along with the abnormal ones.

Symptoms

An enlarged spleen doesn't cause many symptoms, and none of them reveals the specific cause of enlargement. Because the enlarged spleen lies next to the stomach and may press against it, a person may feel full after eating a small snack or even without eating. A person may also have abdominal or back pain in the area of the spleen; the pain may spread to the left shoulder, especially if parts of the spleen don't get enough blood and start to die.

Diagnosis

Usually, a doctor can feel an enlarged spleen during a physical examination. An x-ray of the abdomen may also show that the spleen is enlarged. In some cases, computed tomography (CT) scans are needed to determine how large the spleen is and whether it is pressing on other organs. A magnetic resonance imaging (MRI) scan provides similar information and also traces blood flow through the spleen. Other specialized scanning devices use mildly radioactive particles to assess the spleen's size and function and to determine whether it is accumulating or destroying large numbers of blood cells.

Blood tests show decreased numbers of red blood cells, white blood cells, and platelets. When blood cells are examined under a microscope, their shape and size may provide clues to the cause of the spleen enlargement. An examination of bone marrow (see page 737 in Chapter 152, Biology of Blood) may detect cancer of the blood cells (such as leukemia or lymphoma) or an accumulation of unwanted substances (such as storage diseases). These disorders can cause an enlarged spleen.

Blood protein measurement can help rule out such conditions as multiple myeloma, amyloidosis, malaria, kala-azar, brucellosis, tuberculosis, and sarcoidosis. Levels of uric acid (a waste product found in blood and urine) and of leukocyte alkaline phosphatase (an enzyme found in some blood cells) are measured to determine whether certain leukemias and lymphomas are present. Liver function tests help determine whether the liver is damaged along with the spleen.

Treatment

When possible, a doctor treats the underlying disease that caused the enlarged spleen. Surgical removal of the spleen is rarely necessary and can cause problems, including susceptibility to serious infection. However, these risks are worth taking in certain critical situations: when the spleen destroys red blood cells so rapidly that severe anemia develops; when it so depletes stores of white blood cells and platelets that infection and bleeding are likely; when it is so large that it causes pain or puts pressure on other organs; or when it is so large that parts of it bleed or die. As an alternative to surgery, radiation therapy can sometimes be used to shrink the spleen.

Ruptured Spleen

Because the spleen lies in the upper left part of the abdomen, a severe blow to the stomach area can rupture the spleen, tearing its covering and the tissue inside. A ruptured spleen is the most common serious complication of abdominal injury from car accidents, athletic mishaps, or beatings.

When the spleen ruptures, a large volume of blood may pour out into the abdomen. The spleen's tough outer capsule may contain the bleeding temporarily, but surgery is needed immediately to prevent life-threatening blood loss.

Symptoms

A ruptured spleen makes the abdomen painful and tender. Blood in the abdomen acts as an irritant and causes pain; the abdominal muscles contract reflexively and feel rigid. If the blood leaks out gradually, no symptoms may occur until the body's blood supply is so depleted that blood pressure falls or oxygen can't be transported to the brain and heart. Such a situation is an emergency requiring immediate blood transfusions to maintain adequate circulation and surgery to stop the leak; without these actions, the person could go into shock and die.

Diagnosis and Treatment

X-rays of the abdomen are taken to determine if the symptoms may be caused by something other than a ruptured spleen. Scanning procedures using radioactive material to trace blood flow and find leaks may be performed, or fluid in the abdomen may be withdrawn by a needle and sampled to see if it's bloody. When doctors strongly suspect that the spleen has ruptured, the person is rushed to surgery to stop the potentially fatal loss of blood. Usually the entire spleen is removed, but sometimes surgeons are able to close off a small rupture and save the spleen.

Before and after removal of the spleen, certain precautions are needed to prevent infections. For example, vaccinations against pneumococcus are given before a splenectomy whenever possible, and yearly vaccinations against influenza are recommended after a splenectomy. Many doctors also recommend prophylactic antibiotics.

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Immunopathic (Or autoimmune Liver disease)

Research as indicated that HCV is a *major* cause of type-II autoimmune hepatitis, a relatively rare condition that is characterized by the presence of antibodies to the liver/kidney microsomes.  This is a very serious condition that, if untreated, progresses to cirrhosis within three years in over 80% of patients.  Interestingly some of these patients have been successfully treated with interferon, despite the contraindication. 

Infection with the hepatitis C virus (HCV) can lead to autoimmune hepatitis in a minority of patients. This means that the liver cells are damaged not only by the virus but also by the body's own immune system.

The Connection Between Hepatitis C and Autoimmune Disorders

Autoimmune hepatitis triggers the body to attack its liver cells, as if the liver cells were harmful foreign bodies. Patients with a combination of HCV and autoimmune hepatitis generally suffer from more debilitating symptoms than patients with HCV alone. Autoimmune hepatitis is associated with other autoimmune illnesses, including thyroiditis (inflammation of the thyroid), diabetes mellitus, and ulcerative colitis (inflammation of the intestines). Although only a few patients with HCV develop autoimmune hepatitis, these patients appear to have a genetic predisposition that makes them more likely to develop autoimmune hepatitis, compared to HCV-infected individuals without that predisposition.

Below are some frequently asked questions about the complex relationship between HCV and autoimmune hepatitis.

Q. What are the Symptoms of Autoimmune Hepatitis?

A. The most common symptom is fatigue. Recurrent jaundice frequently develops in severe cases.

Extrahepatic features (those that involve organs and tissue other than the liver) result from the immune system harming] other organs of the body. These symptoms can include amenorrhea (absence of menstrual period), bloody diarrhea (due to ulcerative colitis), abdominal pain, arthritis, rashes, anemia, glomerulonephritis (a form of kidney disease), dry eyes, and dry mouth.

Symptoms of autoimmune hepatitis tend to develop slowly over a period of several weeks or months.

Q. What Causes These Symptoms?

A. When the immune system becomes activated, as in the case of an autoimmune disease, there is increased production of inflammatory cells (T-cells), antibodies, and other inflammatory mediators (chemicals). The overactivated immune system can lead to systemic symptoms of fatigue and low grade fever. Some of the extrahepatic symptoms, such as glomerulonephritis and arthritis, are due to deposits of antibodies that accumulate in the kidney or joints, leading to damage in those tissues.

Q. What is the Process by Which HCV Triggers Autoimmune Conditions?

A. Although the mechanism is still poorly understood, it is theorized that proteins appear on the surface of infected liver cells. This leads to an autoimmune response, in which cells of the immune system (including T and B cells) recognize these new proteins as foreign bodies. These cells then attack the liver, causing inflammation of the liver cells and eventual destruction of liver tissue.

Q. How is Autoimmune Hepatitis Diagnosed?

A. Autoimmune hepatitis requires laboratory tests to distinguish it from uncomplicated hepatitis C infections. Hypergammaglobulinemia, an excess of antibodies in the blood, is a common finding in autoimmune hepatitis. Blood tests for certain autoantibodies may also provide diagnostic clues. The diagnosis may, however, require a liver biopsy.

Q. How is Treatment for Patients with Autoimmunity Determined?

A. Interferon is the only approved treatment for HCV, but its use in people with autoimmune hepatitis has been shown to exacerbate symptoms. In general, steroids are used for people with autoimmune hepatitis due to non-viral causes, but in patients with hepatitis C, steroids can increase viral replication.

A liver biopsy is usually recommended to determine which disease process is causing the greatest damage to the liver: the HCV infection or the autoimmune hepatitis. In general, if the HCV infection were predominant and the autoimmune hepatitis mild, alfa interferon treatment would be considered. However, if the autoimmune hepatitis were severe, leading to such complications as kidney damage, rashes, or rapid liver failure, steroids or other immunosuppressant drugs would more likely be recommended.

The choice between these treatment options boils down to the immune system. Alfa interferon, which activates the immune system to reduce viral replication, could be problematic for those whose immune system was already over-activated due to severe autoimmune hepatitis. Steroids, which suppress the immune system, could be problematic for those with severe HCV-infection, leading to a compromise the body's ability to fight the infection.

Source

Harrison's Principles of Internal Medicine, Thirteenth Edition, 1994, McGraw-Hill, Inc.

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