Blood Disorders

Anemia, Leukopenia, and Thrombocytopenia 

Like any part  of the body, the blood can also be afflicted with diseases  and disorders that can compromise your health. Disorders of the blood range from mild, with no symptoms, to life-threatening medical emergencies. 

The majority  of the blood is plasma, which accounts for about  half of the blood volume. Plasma  is mostly water and contains dissolved salts and proteins, as well as hormones, electrolytes, fats, sugars, minerals, and vitamins.  The other components of blood include: 

• Red  blood cells—Red blood cells are responsible for carrying oxygen from the lungs to all other cells in the body,  and for transporting carbon dioxide back to the lungs.  Red blood cells are produced in the bone marrow. Each red blood cell has a life cycle of about 120 days, at which point they wear out and are destroyed in the spleen. Red blood cells are able to transport  oxygen because of hemoglobin, an iron-containing molecule that binds  to oxygen. About 90 percent of each red blood cell is hemoglobin,  and each molecule of hemoglobin can carry four molecules of oxygen (Eastern Kentucky University 2005). 
• White blood cells—White blood cells are the backbone of the immune system. They  fight infection by engulfing invading organisms or abnormal cells. There are five basic kinds of white blood cells: neutrophils, monocytes, lymphocytes, eosinophils,  and basophils. Neutrophils  are the most common form  of white blood cell and are responsible for fighting infection. 
• Platelets—Platelets are responsible for  blood clotting. They circulate constantly in the bloodstream. In the event of an injury, platelets gather (aggregate) at the injured site and touch off a chemical reaction that results in a blood  clot. Abnormal platelet function may result in increased bleeding or  the formation of dangerous  blood clots where they don’t belong, which can cause a heart attack or stroke. 

In this chapter, we will review three blood disorders—anemia (low red blood cells), leukopenia (low white blood cells),  and thrombocytopenia (low platelets). We will address how these disorders are diagnosed and conventionally treated and how to support the health of  your red  blood cells, white blood cells, and platelets with nutrition. 

What Is Anemia? 

Anemia is a common blood disorder characterized by a decrease in the amount of red blood cells, or a decrease in the capacity of red blood  cells to transport oxygen. This results in a lack of oxygen reaching the body’s cells and tissues. Referred to as the “hidden hunger” by the World Health Organization, anemia poses significant health risks worldwide. It affects between 2 percent and 15 percent of people in the United States (Abrahamian FM et al 2005). Women are  about twice as likely to be anemic as men. This is especially true of premenopausal women; between 4 percent  and 8 percent of premenopausal women have iron deficiency anemia (Abrahamian FM et al 2005; Conrad ME 2005). 

Anemia is associated with poor health outcomes. In patients who have had  a heart attack, anemia sharply increases mortality (Wu RC et al 2001), and it is a strong predictor of overall mortality in the elderly. Over a 5-year period, anemic people aged 70 to 79, 80 to 89, and 90 to 99 were 28 percent, 34 percent, and 48 percent, respectively, more likely to die than people of the same ages who were not anemic. Stroke is commonly associated with anemia (Kikuchi M et al 2001). 

Anemia is associated with the following symptoms (Abrahamian FM et al 2005): 

• Weakness and fatigue 
• Irritability  
• Shortness  of breath 
• Headaches  
• Sore tongue and  bleeding gums 
• Pallor  
• Nausea  and loss of appetite 
• Faintness and dizziness 
• Confusion and dementia 
• Increased heart rate 
• Heart failure (in severe cases) 

Depending on its cause, anemia is generally classified in three ways: excessive bleeding, decreased red blood cell production, or increased red blood cell destruction. 

Excessive bleeding 

This form of anemia occurs when someone loses too much  blood, either because of an injury (acute anemia) or a chronic disease. When the body loses a large amount of blood, the body reacts by pulling water from surrounding tissues into blood vessels to maintain a healthy blood pressure. This dilutes the blood, lowering the proportion of red blood cells. 

Excessive bleeding can result in very serious anemia, depending on the nature of the injury. Acute anemia that involves the rapid loss of great volumes of blood can result in heart attack or stroke (Beers MH 2003). However, anemia related to chronic conditions, such as recurrent nosebleeds or ulcers in the stomach, develops more slowly and  may not be as obvious. This type of anemia sometimes occurs as  a result of cancer, especially colon cancer. 

Chronic blood loss can cause a deficiency in iron. Iron deficiency anemia  is the most common form of anemia (Leung AK et al 2001; Rasul I et al 2001), affecting about 2 billion people worldwide (Lynch SR 2005). It results in decreased red blood cell production. 

Because it can take several months to deplete  the body’s supply of iron, it might take a long time for symptoms to develop. Iron deficiency anemia caused by blood loss is one of the most common forms of anemia in the United States (Beers MH 2003). In women, this condition is frequently related to excessively heavy menstrual bleeding; in men, it is often related to gastrointestinal bleeding. 

Decreased red blood cell production 

Red blood cells are manufactured in the bone marrow. This process relies on various nutrients, including iron, vitamin B12,  and folic acid, as well as smaller amounts of vitamin C, riboflavin, and copper. Also, the production of red blood cells is stimulated by a hormone called erythropoietin. Deficiencies in any of these nutrients or in erythropoietin can result in anemia. Besides iron deficiency anemia caused by bleeding,  other forms of anemia includes: 

• Pernicious anemia (vitamin B12 deficiency)—It  is estimated that 300,000 to 3 million people in the United States have a vitamin B12 (cobalamin) deficiency (Diamond AL et al 2004). Vitamin B12 deficiency is rarely related to a dietary deficiency. Rather, vitamin B12 relies on intrinsic factor, a protein generated by cells in the stomach, to be bound to vitamin B12 and then absorbed in the ileum, the last segment of the small intestine. People who lack intrinsic factor  cannot use the available vitamin B12, meaning that anemia can develop even if large amounts of vitamin B12 are consumed. Besides a lack of intrinsic factor, pernicious anemia can  be caused by Crohn's disease, stomach surgery,  or a strict vegetarian diet. Breast-fed infants of vegan mothers  are particularly at risk of vitamin B12 deficiency. 
• Folic acid deficiency anemia—Folic acid is abundant in green leafy vegetables. Because many people in industrialized countries don't eat enough vegetables, folic acid deficiency is more common than pernicious anemia. Folate deficiency is found in malnourished individuals (especially alcoholics), infants who are fed  only cows’ milk, pregnant women, and adults over age 60. It can also be caused by diseases that affect absorption in the small intestine, including Crohn's disease. 
• Anemia  of chronic disease—Anemia is associated with various chronic diseases and conditions, including infections, inflammatory diseases, and cancers that affect the ability of the body to produce red  blood cells (Brill JR et al 2000; Bron D et al 2001). Diseases or conditions that are associated with anemia include cancer (Gillespie TW 2003; Knight K et al 2004), HIV/AIDS (Sullivan PS et al 1998), and testosterone deficiency (Bain J 2001; Zitzmann M et al 2000). In  patients with cancer or HIV/AIDS, anemia is associated with increased mortality (Buskin SE et al 2004; Caro JJ et al 2001). Testosterone deficiency can cause anemia because the hormone helps stimulate kidneys and bone marrow to produce erythropoietin and stem cells. Symptoms of testosterone deficiency include decreased libido, impotence, infertility, fatigue, and decreased muscle mass and strength (Baker HWG 1995). 

Additionally, aplastic anemia is a rare form  of anemia that occurs when bone marrow fails to produce all three types of  blood cells:  red blood cells, white blood cells, and platelets. Causes of aplastic anemia include autoimmune diseases, viruses, or chemicals (e.g., benzene or pesticides). Symptoms include frequent infections (white blood cells are reduced), fatigue (red blood cells are reduced), and bleeding (platelets are reduced). 

Increased red blood cell destruction 

If the rate of red blood destruction is more rapid than the creation of new red blood cells, hemolytic anemia occurs. This form of anemia is less common than the other two. Hemolytic anemia can result from infection, certain drugs, autoimmune disorders in which the body attacks and destroys its own red blood cells, and inherited disorders such as sickle cell anemia or thalassemia. 

Additionally, an enlarged spleen can result in anemia. The spleen is responsible for destroying old red blood cells; an enlarged spleen can increase the rate of red blood cell destruction beyond the body’s ability to manufacture new red blood cells. 

Sickle cell anemia is the most common inherited blood disorder in the United States, affecting 1 in 500 African Americans and 1 in 2000 Hispanics of Caribbean or South or Central American descent (Pegelow C et al 2004). In this disease, the red blood cells are abnormally shaped (they resemble boomerangs), and their blood carrying capacity is reduced. These cells are fragile and break up as they travel through blood vessels, resulting in a reduced red blood cell count. 

Thalassemia occurs when there is an imbalance in the production of one of the amino acid chains that makes up hemoglobin. Many people who have thalassemia also have mild anemia. 

Autoimmune disorders can cause anemia if the body identifies red blood cells as invader pathogens and attacks them. In most people, the cause of autoimmune anemia is unknown (Beers MH 2003). 

Notes: DrJMinor

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EditText of this page (last edited December 23, 2009)