Anemia

Anemia (meaning lack of blood) is a medical condition in which the red blood cell (RBCs) count or hemoglobin decreases than normal number. The normal level of hemoglobin generally differs in males and females. For men, anemia is detected if the hemoglobin level is less than 13.5 gram/100ml and in case of women the hemoglobin decreases to 12.0 gram/100ml. A person having low hemoglobin level or anemia is called anemic. This can lead to health problems hampering oxygen binding ability (hypoxia) because hemoglobin carries oxygen to the body\’s tissues. Anemia can also cause a variety of complications, such as fatigue and stress on bodily organs.

What causes anemia?

Many things can lead to anemia. Any process that can disturb the normal life span of a red blood cell may result in anemia. Normal life span of a red blood cell, formed in the bone marrow, is usually around 120 days.

Anemia is generally brought about by 3 main bodily mechanisms:

As more common classifications of anemia (low hemoglobin) is based on the MCV, or the volume of individual red blood cells.

Classification of anemia:

1. If the MCV is less than 80, the anemia is termed as Microcytic anemia (low cell volume).
2. If the MCV is in the normal range (80<MCV<100), it is called a Normocytic anemia (normal cell volume).
3. If the MCV is greater than 100, then it is known as Macrocytic anemia (large cell volume).

Many medical conditions cause anemia.

Anemia from active bleeding:Loss of blood owing to heavy menstrual bleeding or, serious injury can cause anemia. Gastrointestinal ulcers or cancers such as cancer of the colon may slowly leak blood and can also cause anemia. Other conditions include frequent blood sampling for laboratory tests, Surgery causing severe blood loss etc.

Iron deficiency anemia:The bone marrow requires iron to produce red blood cells. Iron plays a crucial role in the proper buildup of the hemoglobin molecule. Limited or inadequate iron intake due to poor dietary intake may result in anemia. This is known as iron deficiency anemia.

Anemia of chronic disease:Any long-term medical condition can cause anemia. But the exact mechanism of this process is not known, but any prolonged and ongoing medical condition such as an infection or a cancer may result in this type of anemia due to chronic diseases.

Anemia related to kidney disease:The kidneys release erythropoietin hormone that helps the bone marrow produce red blood cells. In people with chronic (long-standing) kidney disease, the production of this hormone is reduced, and this in turn lessens the formation of red blood cells, causing anemia. This is called anemia related to chronic kidney disease.

Anemia related to pregnancy:Gain of water during pregnancy dilutes the blood, which may be seen as anemia.

Anemia related to poor nutrition:

Vitamins and minerals make red blood cells. In addition to iron, vitamin B12 and folate are required for the suitable production of hemoglobin. Lack of any of these may result in anemia because of insufficient production of red blood cells. Poor dietary intake is a significant cause of low folate and low vitamin B12 levels. Strict vegetarians who do not take sufficient vitamins are likely to develop vitamin B12 deficiency.

Pernicious Anemia:There also may be a problem in the stomach or the intestines that cause poor absorption of vitamin B12. This may lead to anemia due to vitamin B12 deficiency and is known as pernicious anemia.

Sickle cell anemia:In some individuals, the problem may occur due to abnormal hemoglobin molecules. In such condition the hemoglobin problem is qualitative, or functional in nature. Abnormal hemoglobin molecules disturb the integrity of the red blood cell structure and they may develop into crescent-shaped (sickle cells). There are different types of sickle call anemia with diverse severity levels. This is characteristically hereditary and is more common in those of African, Middle Eastern, and Mediterranean ancestry.

Thalassemia:This is another group of hemoglobin-related causes of anemia. There are various types of thalassemia varying in severity. These are also hereditary, but they bring about quantitative hemoglobin abnormalities, meaning the production of an inadequate number of hemoglobin molecules.

Alcoholism:

Poor nutrition and vitamin and mineral deficiencies are related to alcoholism. Alcohol itself may also be lethal to the bone marrow and may decelerate the production of red blood cells. The combination of these factors may cause anemia in alcoholics.

Bone marrow-related anemia:Anemia may be related to diseases involving the bone marrow. Some blood cancers including leukemia or lymphomas can change the production of red blood cells and cause anemia. Other processes may be associated with a malignancy from another organ spreading to the bone marrow.

Aplastic anemia:Sometimes some viral infections may seriously do harm to the bone marrow and reduce production of all blood cells. Chemotherapy (cancer medications) and some other medications may produce the same problems.

Hemolytic anemia:The normal red blood cell shape is essential for its function. In case of Hemolytic anemia the red blood cells are damaged (hemolysis) and become dysfunctional. This could be due to a variety of reasons. Some forms of hemolytic anemia are hereditary. In this case the constant destruction and rapid reproduction of red blood cells take place. This destruction may also disrupt normal red blood cells in certain conditions, for example, with abnormal heart valves damaging the blood cells.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency:This most commonly affects males belonging to African heritage. But it has been also found in many other groups of people. In such situation RBCs either do not make sufficient enzyme G6PD or the enzyme produced is abnormal and doesn\’t work efficiently. When someone born with this deficiency has an infection, takes certain medicines, or is exposed to specific substances, the body\’s RBCs experience extra stress.

Hereditary spherocytosis:It is a genetic confusion of the RBC\’s membrane causing anemia, jaundice (yellow-tinged skin), and enlargement of the spleen. The RBCs have a lesser surface area in comparison to normal red blood cells, which can cause them to break open effortlessly. A family history heightens the risk for this disorder, which is widespread in people of northern European descent but can affect all races.

Other less common causes of anemia are medication side effects, thyroid problems, cancers, liver disease, other genetic disorders, lead poisoning, AIDS, and bleeding disorders.

Symptoms

Signs and symptoms vary depending on the cause of your anemia. The signs may include:

Fatigue
Pale skin
A fast or irregular heartbeat
Shortness of breath
Chest pain
Dizziness
Cognitive problems
Cold hands and feet
Headache

Initially, anemia can be so mild it goes unobserved. But signs and symptoms increase as anemia aggravates.

Exams and Tests

Anemia is generally detected or at least confirmed by a complete blood cell (CBC) count.

Complete blood count:This determines the severity and type of anemia (microcytic anemia or small sized red blood cells, normocytic anemia or normal sized red blood cells, or macrocytic anemia or large sized red blood cells) and is typically the first test recommended by your doctor..

Blood smear examination:Blood is smeared on a glass slide to carry out a microscopic examination of RBCs, which can sometimes denote the cause of the anemia.

Iron tests:In this test total amount of serum iron and ferritin are considered, which can help to determine whether anemia is due to iron deficiency.

Hemoglobin electrophoresis:This test is useful to detect abnormal hemoglobin in blood and to diagnose sickle cell anemia, the thalassemia, and other inherited forms of anemia.

Bone marrow aspiration and biopsy:This test is helpful to determine if cell production is going on normally in the bone marrow. It\’s the only possible way to diagnose aplastic anemia definitively and is also used if a disease affecting the bone marrow (such as leukemia) could be resulting in the anemia.

Reticulocyte count:It is a measurement of young RBCs, which helps determine if RBC production is at normal levels.

Treatment

Treatment for anemia can be ensured only after finding its cause. Treatment for more severe or chronic forms of anemia may include:

Transfusions of normal red blood cells taken from a donor
Removal of the spleen or treatment with medications to restrict blood cells from being removed from circulation or destroyed so swiftly.
Medications to fight infection or stimulate the bone marrow to make more blood cell

Treatment for iron deficiency anemia:This form of anemia is treated with iron supplements, which you may need to consume for several months or even longer. If the main cause of iron deficiency is loss of blood (but not due to menstruation) the source of the bleeding must be detected and stopped. This may also involve surgery

Treatment for vitamin deficiency anemia:Pernicious anemia is treated with injections (often lifetime injections) of vitamin B-12. On the other hand Folic acid deficiency anemia is generally treated by recommending folic acid supplements

Anemia of chronic disease:There\’s no particular treatment for this type of anemia that takes place due to chronic disease. Doctors generally focus on treating the core disease. Iron supplements and vitamins generally don\’t seem beneficial for this type of anemia. However, if symptoms deteriorate, a blood transfusion or injections of synthetic erythropoietin, a hormone which is normally produced by your kidneys, may help encourage red blood cell production and ease fatigue

Aplastic anemia:Blood transfusions may require boosting levels of red blood cells. You may need a transplantation of bone marrow if your bone marrow is diseased and can\’t produce healthy blood cells. You may need immune-suppressing medications to reduce your immune system\’s response and give the transplanted bone marrow an opportunity to start acting again.
If the anemia is associated with bone marrow disease the treatment of these various diseases can vary from simple medication to chemotherapy to bone marrow transplantation.

Hemolytic anemia:The treatment of hemolytic anemia is initially performed by avoiding suspect medications. Treating related infections and taking drugs useful to suppress your immune system, which may affect your red blood cells are required. Short course treatment with steroids, immune suppressant medications or gamma globulin can help curb your immune system\’s attack on your red blood cells.

If the condition has resulted in an enlarged spleen, doctor may suggest you to remove your spleen which is comparatively a small organ below your rib cage on the left side. It filters out and stores diseased red blood cells. Certain hemolytic anemia can cause your spleen to become inflated with damaged red blood cells. Sometimes, the spleen acts well to cause hemolytic anemia by removing too many red blood cells. Depending on the proximity of your anemia, a blood transfusion or plasmapheresis a type of blood-filtering procedure may be done

Sickle cell anemia:Treatment for sickle cell anemia is performed by administration of oxygen, pain-relieving drugs, and oral and intravenous fluids to decrease pain and prevent complications. Doctors also commonly use blood transfusions, folic acid supplements and antibiotics to treat sickle cell anemia. A bone marrow transplant is considered an effective treatment in some cases. A cancer drug called hydroxyurea (Droxia, Hydrea) is also recommended to treat sickle cell anemia in adults.

Epoetin alfa (Procrit or Epogen):

Injection can be given to increase production of red blood cells specifically in people with kidney problems. The production of erythropoietin hormone is reduced in people who have advanced kidney disease.

Preventing Anemia

The prevention of anemia depends on its cause. At present, there is no means to prevent anemia due to genetic defects disrupting the production of RBCs or hemoglobin. However, you can help avoid iron deficiency anemia and vitamin deficiency anemia by following a healthy, varied diet, including:

Iron: Beef and other meats are the best sources of iron. Other foods rich in iron include beans, lentils, peas, iron-fortified cereals, dark green leafy vegetables, dried fruit, peanut butter and nuts.

Folate: This nutrient, and its synthetic form, that is folic acid, is present in citrus juices and fruits, bananas, dark green leafy vegetables, legumes and fortified breads, cereals and pasta.

Vitamin B-12: This vitamin remains in considerable amount in meat and dairy products.

Vitamin C: Citrus fruits, melons and berries are rich in vitamin C and help increase iron absorption.

Well-balanced diet: A balanced diet includes iron-fortified grains and cereals, red meat, egg yolks, leafy green vegetables, yellow vegetables and fruits, potato skins, tomatoes, molasses, and raisins. In case of a vegetarian, an extra effort must be ensured to include sufficient iron sources because iron present in meat, poultry, and fish is more easily absorbed than plant-based iron and iron-fortified foods. Also, be careful that certain food combinations can reduce or promote absorption of iron. For instance, drinking coffee or tea (including iced tea) with a meal can significantly reduce the amount of iron absorbed. On the other hand, vitamin C encourages the body to absorb iron.

Cow\’s milk consumption: During the first 6 months of life, babies do not usually develop iron deficiency because of the stores of iron formed in their bodies before birth. But after month 6, they often don\’t receive enough iron through breast milk alone or regular cow\’s milk because cow milk contains lesser iron than fortified infant formula. Strikingly regular cow\’s milk can even cause some infants to lose iron from their intestines, and having lots of cow milk can make a baby less concerned in eating other foods that are rather better sources of iron. Therefore regular cow\’s milk is not suggested for children until they reach 1 year of age and are get ready to eat an iron-rich diet. Moreover, they should not be given more than 24-32 ounces (709-946 ml) of milk each day.

	WHO\’s Hemoglobin thresholds used to define anemia (1 g/dL = 0.6206 mmol/L)
Age or gender group	Hb threshold (g/dl)	Hb threshold (mmol/l)
Children (0.5–5.0 yrs)	11.0	6.8
Children (5–12 yrs)	11.5	7.1
Children (12–15 yrs)	12.0	7.4
Women, non-pregnant (>15yrs)	12.0	7.4
Women, pregnant	11.0	6.8
Men (>15yrs)	13.0	8.1