Iron Deficiency Anemia

What is Anemia?

Anemia is defined as a decreased number of red blood cells (or RBCs) as measured by one of the following blood tests:

  1. Hemoglobin
    1. This is the iron-containing molecule found in our red blood cells that carries oxygen to our cells and tissues.
    2. Iron is a critical component of hemoglobin. Without iron, hemoglobin can’t be made.
    3. Our red blood cells only live for 120 days. After that, they are removed from the bloodstream by the spleen, liver and bone marrow and recycled and new cells are made.
    4. Without iron, we can’t make new hemoglobin, and without new hemoglobin we can’t make new red blood cells, so the less iron you have in your body the fewer red blood cells your body can produce. This ultimately results in anemia.
  2. Hematocrit is the percentage of red blood cells in your blood.
  3. The red blood cell count is the number of red blood cells in your blood.

What is iron deficiency and anemia?

There are many types of anemia. Iron deficiency anemia is a specific type of anemia that occurs when there is not enough iron to make the hemoglobin found in red blood cells.

What causes iron deficiency anemia?

Iron deficiency anemia occurs when there is not enough iron in the body to make hemoglobin.

Iron deficiency anemia can be caused by a number of different conditions. The main causes of iron deficiency anemia in adults in our society are:

  1. Bleeding, and
  2. Decreased absorption of iron from the food that we eat.

1. Bleeding or Blood Loss

The source of blood loss may be obvious, such as in women who have heavy menstrual bleeding or who have had multiple recent pregnancies or deliveries, or in a person with a known bleeding ulcer or mass.

In other cases, the source of the blood loss may not be so obvious, as in someone who has chronic bleeding from their GI tract. This may appear as diarrhea with black, tarry stools, or, if the blood loss is very slow, the stool may appear normal.

Donating blood can also cause iron deficiency, especially if it is done on a regular basis.

2. Decreased absorption of iron from the diet

Normally, the body absorbs iron from our food through the GI tract. If the GI tract is not functioning properly this can lead to iron deficiency and anemia. Conditions that can cause decreased iron absorption include:

  1. Celiac disease,
  2. Lactose intolerance,
  3. Autoimmune gastritis,
  4. Stomach inflammation,
  5. Gastric bypass surgery,
  6. Other forms of weight loss surgery.

Other causes

A common cause of iron deficiency anemia in developing countries is a lack of foods that contain iron. This is rarely seen in adults in developed countries because many foods contain iron, and others are fortified with iron.

Pregnant and postpartum women may develop iron deficiency anemia because of the increased iron requirements of the growing fetus and placenta, and blood loss at delivery.

Iron deficiency anemia can be a symptom of certain types of cancer like colorectal cancer so ALL anemia should be evaluated promptly and aggressively by a trained medical professional like Dr. Sinha.

How common is iron deficiency anemia?

Iron deficiency anemia common in the United States, especially in women who are still menstruating or who are pregnant.  It occurs in roughly 2-10% of the population. It is less common in men.

It can be a sign of underlying GI disease such as colorectal cancer so any iron deficiency anemia, especially in a man or in a woman who is not menstruating or pregnant, needs to be evaluated promptly and aggressively to avoid delayed diagnosis and delayed care.

Who is at risk for developing iron deficiency anemia?

  1. Women who are still menstruating, have heavy periods, or who are pregnant.
  2. It is more common in developing countries, due to deficiencies of iron in the diet.
  3. Women with a history of abnormal uterine bleeding, multiple pregnancies,and/or
  4. Individuals with GI conditions such as ulcers, Helicobacter pylori (or H. pylori) infection, autoimmune gastritis, celiac disease or lactose intolerance
  5. People who have had GI surgery (especially gastric bypass surgery)
  6. People with a family or personal history of bleeding disorders
  7. People with a family or personal history of colorectal cancer
  8. People who donate blood on a regular basis
  9. People who use certain medications that can irritate the GI tract, such as nonsteroidal anti-inflammatory drugs (NSAIDs), Aspirin and other blood thinners
  10. People who have any symptoms of GI bleeding such as dark black, tarry stools, abdominal pain, or visible bleeding

What are the symptoms of iron deficiency anemia?

Symptoms of iron deficiency may vary from person to person. Iron deficiency can cause symptoms in the absence of anemia; however, many people with iron deficiency will not have any symptoms until they become anemic. Symptoms of anemia include:

  1. Fatigue,
  2. Weakness
  3. Sluggishness
  4. Headache
  5. Irritability
  6. Difficulty exercising
  7. Shortness of breath,
  8. Rapid heartbeat,
  9. Pounding heartbeat
  10. Lightheadedness
  11. Dizziness
  12. Fainting
  13. Brittle nails
  14. Sore tongue or mouth ulcers
  15. Restless legs
  16. An abnormal craving to eat unusual non-food items such as clay or dirt, paper products, and/or cornstarch
  17. An abnormal craving to eat ice

How is iron deficiency anemia diagnosed?

The initial workup generally involves a comprehensive medical history, physical examination, and blood tests.

  1. A complete blood count or CBC is ordered to look at your red blood cell count, hemoglobin, and hematocrit, and platelet counts. It also includes other tests that look at the size, shape, color and other characteristics of your red blood cells.
  2. Other blood tests might include serum iron, total iron binding capacity (or transferrin), Transferrin saturation, and Ferritin (a protein that stores iron in the liver and spleen).

How is iron deficiency anemia worked up? What other tests might I expect?

Once a diagnosis is made, our team will search for a source of blood and iron loss. It is important to identify the cause of your blood loss. We will take a thorough history and order the appropriate tests to work up your condition.

Additional blood tests for certain conditions that interfere with iron absorption such as autoimmune gastritis, celiac disease, lactose intolerance, and H. pylori infection may be ordered.

Additional diagnostic tests may include a colonoscopy, upper endoscopy, small bowel capsule endoscopy, or CT enterography to look for areas of bleeding in the GI tract.

What is the treatment for iron deficiency anemia?

The first step in treating iron deficiency anemia is to determine the cause of the deficiency and to correct it, so that iron does not continue to be lost, and any serious conditions like colorectal cancer are identified and treated as early as possible.

After that, the treatment for iron deficiency anemia is iron therapy. Iron supplements may be taken by mouth or IV (through a vein).

Oral iron tablets are used in most people with iron deficiency anemia. Intravenous iron can be used for people whose GI tract is unable to adequately absorb iron or in those who are unable to tolerate oral iron.

A blood transfusion may be given if a person is actively bleeding and/or the hemoglobin or hematocrit is so low that an individual is not hemodynamically stable.

Oral iron

Oral iron tablets are usually a safe, inexpensive, and effective treatment for people with iron deficiency. A few tips for those prescribed iron therapy include:

  1. Taking your iron every other may actually be more effective than taking it every day. This gives the body time to absorb more iron and reduces your risk for GI side effects.
  2. Enteric coated iron tablets are not recommended because iron is best absorbed from the duodenum and jejunum (the first and middle portions of the small intestine). Enteric coated iron releases iron further down in the intestinal tract, where it is not as easily absorbed.
  3. Iron tablets usually should not be taken with food, certain antibiotics, tea, coffee, calcium supplements, or milk. These things can decrease absorption. Iron should be taken one hour before or two hours after these items.
  4. If you take antacids, your iron tablets should be taken two hours before or four hours after the antacids.
  5. Taking your iron with vitamin C tablet or orange juice can enhance absorption.

What are the side effects of iron therapy?

  1. Common side effects include: a metallic taste, nausea, constipation, stomach upset, dark-colored stools,and/or
  2. Taking iron tablets will turn the stool a dark, almost black color. This is to be expected, and does NOT mean that the iron tablets are causing intestinal bleeding.

Can I correct my iron deficiency anemia simply by increasing the iron in my diet? Do I have to take iron pills?

Although dietary iron is important in preventing iron deficiency, people with iron deficiency anemia typically need more iron than they can consume through their diet alone. Therefore, increasing dietary iron alone is not usually recommended as a treatment for iron deficiency anemia, although it may be recommended in combination with iron therapy.

Good dietary sources of iron are found in meat, grains, fruits, and vegetables. Plant sources of iron include whole or enriched breads or grains, iron-fortified cereals, legumes, green leafy vegetables, and dried fruits. Iron-rich foods should not be consumed with coffee or tea, and taking vitamin C or drinking orange juice with iron rich foods can help with absorption.

How can I prevent iron deficiency anemia?

People who have had iron deficiency anemia once may be at increased risk for developing it again, depending upon why they developed the condition initially. Maintain a balanced diet. Watch for symptoms of GI blood loss. If you have heavy periods, discuss treatment options with your primary care provider or gynecologist.

Iron supplements and multivitamins that contain iron should NOT be taken unless prescribed. Most men and postmenopausal women do NOT need supplemental iron unless they have an underlying illness that reduces iron absorption or causes bleeding.

What about other types of anemia? What causes them?

  1. Anemia of chronic disease: Any long-term medical condition can lead to anemia for a variety of reasons.
  2. Kidney disease: The kidneys release a hormone called erythropoietin that tells the bone marrow to produce more red blood cells when necessary. In people with chronic or end stage kidney disease, the production of this hormone is diminished, which diminishes red blood cell production and can lead to anemia.
  3. Pregnancy: Water weight and fluid gain during pregnancy can dilute the blood, which can be reflected as anemia. The added nutritional demands of the developing fetus can also contribute to anemia during and after pregnancy
  4. Post-partum anemia: related to blood loss during delivery
  5. Poor nutrition: Vitamin B12 and folic acid are necessary for the production of new red blood cells. Strict vegetarians who do not take in sufficient vitamins are at risk to develop B12 deficiency. Also, individuals who have had gastric bypass surgery are not able to absorb nutrients from food sources as well as people with normal GI anatomies. This can result in nutritional deficiencies and anemia.
  6. Pernicious anemia: This is a specific type of anemia caused by poor absorption of vitamin B12 which is needed for your body to make new healthy red blood cells
  7. Sickle cell anemia: This is a hereditary condition where there aren't enough healthy red blood cells to adequately carry oxygen throughout your body. Red blood cells are classically shaped like “sickles”. This condition is more common in people of African, Middle Eastern, and Mediterranean ancestry.
  8. Thalassemia: this is a hereditary condition where the body makes an abnormal form, or inadequate amount, of hemoglobin. It is more common in people from African, Mediterranean, and Southeast Asian ancestries.
  9. Alcoholism: Poor nutrition and deficiencies of vitamins and minerals associated with alcoholism can lead to anemia. Alcohol can also be toxic to the bone marrow, which can slow down the production or red blood cells resulting in anemia.
  10. Bone marrow-related anemia: Some blood cancers such as leukemia and lymphoma can alter the production of red blood cells and result in anemia.
  11. Aplastic anemia: this is a condition where the bone marrow malfunctions and stops producing enough red blood cells, white blood cells, and platelets.
  12. Hemolytic anemia: this is a type of anemia where the red blood cells rupture and become dysfunctional. This could happen for a variety of reasons including: hereditary spherocytosis, hereditary elliptocytosis, and glucose-6-phosphate dehydrogenase or G6GD deficiency, valvular heart disease, and kidney disease to name a few.
  13. Medications: anemia can be a side effect of many medications. The mechanisms by which these medications cause anemia are numerous and specific to each medication.
  14. Other less common causes of anemia include: thyroid disease, cancers, liver disease, lupus, autoimmune conditions, paroxysmal nocturnal hemoglobinuria, lead poisoning, parasitic infections, mono, other viral conditions, malaria, hepatitis, bleeding disorders, and others.

The information on this website is to provide general guidance. In no way does any of the information provided reflect definitive medical advice and self diagnoses should not be made based on information obtained online. It is important to consult a best in class gastroenterologist regarding ANY and ALL symptoms or signs as it may a sign of a serious illness or condition. A thorough consultation and examination should ALWAYS be performed for an accurate diagnosis and treatment plan. Be sure to call a physician or call our office today and schedule a consultation.

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