Leukemia Blood and Bone Marrow

Leukemia

Blood and bone marrow are part of the circulatory system, specifically part of the cardiovascular system. Blood travels through the body in blood vessels. There are two types of blood vessels, arteries and veins. Arteries carry oxygenated blood from the heart to the rest of the body, while veins carry deoxygenated blood back to the heart. Blood also receives nutrients from the intestines and carries waste back to the intestines or kidneys for disposal. Blood also carried white blood platelets, which can fight germs, to areas containing infections (See generally, My Health Code). According to the Leukemia and Lymphoma society, "Leukemia is a malignant disease (cancer) of the bone marrow and blood. It is characterized by the uncontrolled accumulation of blood cells" (2010). Leukemia begins in the bone marrow, where cells undergo leukemic changes, and them multiply into many cells, eventually crowding out normal blood cells. Normal blood cells are divided into three types: red cells, platelets, and white cells. White cells are further divided into two sub-types: germ ingesting cells like neutrophils and monocytes, and lymphocytes, which actively fight infection.

Therefore, it should come as no surprise that some of the signs and symptoms of leukemia include: lack of energy, shortness of breath, paleness, mild fever, night sweats, slow rate of healing, unexplained bruises, low white blood cell count, anemia, or frequent infections (See generally, Leukemia and Lymphoma, 2010).

Discussion

Leukemia is actually a general term used to describe four different diseases: acute myelogenous leukemia (AML), acute lymphocytic leukemia (ALL), chronic myelogenous leukemia (CML), and chronic lymphocytic leukemia (CLL). Acute leukemias are those leukemias composed primarily of blast cells, and they generally progress rapidly without medical intervention. Chronic leukemias are those leukemias that generally involve fewer blast cells, and tend to progress more slowly, even without medical intervention. Lymphocytic leukemias, sometimes referred to as lymphoblastic, are those leukemias where cellular changes occur in the marrow cells that form lymphocytes. Myelogenous leukemias, sometimes referred to as myeloid, refer to those leukemias where cell changes take place in other marrow cells.

In acute leukemias, the "original acute leukemia cell goes on to form about a trillion more leukemia cells" (Leukemia and Lymphoma, 2010). Because these cells are abnormal, they do not work like normal cells, which results in immediate impairment of circulatory function. Moreover, the abnormal cells crowd out the normal cells in the marrow, which results in a reduction in the number of new normal cells made in the marrow. This causes anemia, a drop in the number of red cells or hemoglobin in the blood, which can impair the oxygen-carrying capacity of the blood. This reduction in the number of normal cells can also lower the body's ability to fight infection, and can result in bruising and easy bleeding (See generally Leukemia and Lymphoma, 2010).

The two types of chronic leukemia must be discussed separately. In CML, "the leukemia cell that starts the disease makes blood cells (red cells, white cells and platelets) that function almost like normal cells" (Leukemia and Lymphoma, 2010). Moreover, the number of red cells usually declines in CML, which causes anemia (Leukemia and Lymphoma, 2010). CML does not tend to reduce the number of white cells or platelets, and their performance remains somewhat normal, however their counts are high and can continue to rise, causing health complications (Leukemia and Lymphoma, 2010). If white blood counts rise too high, blood flow can slow down, causing severe anemia (Leukemia and Lymphoma, 2010).

In CLL, the leukemia cell makes lymphocytes that do not function properly, instead, "the leukemia cell that starts the disease makes too many lymphocytes that do not function. These cells replace normal cells in the marrow and lymph nodes. They interfere with the work of normal lymphocytes, which weakens the patient's immune response" (Leukemia and Lymphoma, 2010). As in CML, the high number of leukemic cells can crowd out the number of normal cells, leading to anemia. However, CLL can also result in "low neutrophil and platelet counts" (Leukemia and Lymphoma, 2010). However, CLL does not tend to cause the out-of-control growth of white blood cells, so it generally does not have the immediate negative health impacts of the other three types of leukemia. Instead, some patients diagnosed with CLL may not require immediate treatment and may not notice any impact on their health or well-being for a significant time period after diagnosis.