IDA – Iron deficiency anemia: Description, Causes and Risk Factors:
Alternative Name: Hypoferric anemia.
Sources of iron-rich foods include:
- Chicken and turkey.
- Dried lentils, peas, and beans.
- Eggs (yolk).
- Meats (liver is the highest source).
- Peanut butter.
- Whole-grain bread.
- Raisins, prunes, and apricots.
- Spinach, kale, and other greens.
Iron is present in many foods and absorbed into the body through the stomach. During this process of absorption, oxygen combines with iron and is transported into the plasma portion of blood by binding to transferrin. From there, iron and transferrin are used in the production of hemoglobin (the molecule that transports oxygen in the blood), stored in the liver, spleen, and bone marrow, and utilized as needed by all body cells.
Iron deficiency results when iron demand by the body is not met by iron absorption from the diet. Thus, patients with IDA presenting in primary care may have inadequate dietary intake, hampered absorption, or physiologic losses in a woman of reproductive age. It also could be a sign of blood loss, known or occult. IDA is never an end diagnosis; the work-up is not complete until the reason for IDA is known.
The main causes of iron deficiency are: poor absorption of iron by the body (Vitamin C aides in iron absorption), inadequate daily intake of iron, pregnancy, growth spurts or blood loss due to heavy period or internal bleeding. Iron deficiency can occur during rapid periods of growth; for this reason nature makes certain that a developing fetus, newborn and infant up the age of about six months has an ample supply of iron. These conditions also can result in iron deficiency: blood loss from heavy menstruation, pregnancy, frequent or excessive blood donation, fibroids, digestive tract disease (including infections), surgery or accidents; medications, supplements or substances that cause bleeding such as pain relievers, poisoning from lead, toxic chemicals or alcohol abuse.
Diets that do not include heme iron, the form of iron in red meat, which is absorbed more efficiently than non-heme iron found in plants and dietary supplements or sufficient iron or other nutrients such as vitamin C, B12, folate or zinc.
Consuming foods, substances or medications that interfere with the absorption of iron such as: taking antacids, proton pump inhibitors (to treat acid reflux), calcium supplements, dairy products, coffee, tea, chocolate, eggs, and fiber. Or diseases and conditions that lower iron absorption, such as: not enough stomach acid, lack of intrinsic factor (hormone needed to absorb vitamin B12); celiac disease, inflammatory conditions such as Crohn’s disease, autoimmune disease and hormone imbalances.
Iron deficiency can also alter the production of triiodothyronine (T3) and thyroid function in general, and the production and metabolism of catecholamines and other neurotransmitters. This results in impaired temperature response to a cold environment.
Other causes may include:
- Blood loss from the gastrointestinal tract is the most common cause of iron deficiency anaemia (IDA) in adult men and postmenopausal women.
- Blood loss due to menorrhagia is the most common cause of iron deficiency in premenopausal women.
- In other countries, infestation of the gut may cause IDA, especially with hookworm and schistosomiasis.
- Other gastrointestinal tract malignancies.
- Bleeding esophageal varices.
- Inflammatory bowel disease.
- Esophagitis and gastroesophageal reflux disease.
- Postpartum hemorrhage.
- Recurrent epistaxis.
- Malignancy of the renal tract.
- After major surgery or major trauma, if replacement has been inadequate.
- After blood donation.
High-risk groups include: women of child-bearing age who have blood loss through menstruation; pregnant or lactating women who have an increased requirement for iron; infants, children, and adolescents in rapid growth phases; and people with a poor dietary intake of iron through a diet of little or no meat or eggs for several years.
A person who is iron deficient may also be anemic and therefore have one or more symptoms of anemia—chronic fatigue, weakness, dizziness, headaches, depression, sore tongue, sensitivity to cold (low body temp), shortness of breath doing simple tasks (climbing stairs, walking short distances, doing housework), restless legs syndrome and loss of interest in work, recreation, relationships and intimacy.
Signs may include:
- Pale complexion.
- The normally red lining of the mouth and eyelids fades in color.
- Rapid heartbeat (tachycardia).
- Abnormal menstruation (either absence of periods or increased bleeding)
- Spoon-shaped finger nails and toenails.
To diagnose IDA, your doctor may order these blood tests:
- Hematocrit and hemoglobin (red blood cell measures).
- RBC indices.
Tests to check iron levels in your blood include:
- Iron binding capacity (TIBC) in the blood.
- Serum ferritin.
- Serum iron level.
- Zinc protoporphyrin (ZPP).
- Free erythrocyte protoporphyrin (FEP)
- Reticulocyte hemoglobin content (CHr).
Tests that may be done to look for the cause of iron deficiency:
- Bone marrow exam (rare).
- Examine the abdomen for abdominal masses, organomegaly, lymphadenopathy and any other features of intra-abdominal disease.
- Perform a rectal examination to look for signs of bleeding, melena and masses.
- If menorrhagia is thought to be the cause: perform a vaginal/bimanual examination, examine the cervix and perform a cervical smear and swabs as appropriate.
Specific treatment for iron-deficiency anemia will be determined by your physician based on:
- Your age, overall health, and medical history.
- Your tolerance for specific medications, procedures, or therapies.
Transfusion should be considered for patients of any age with IDA complaining of symptoms such as fatigue or dyspnea on exertion. It also should be considered for asymptomatic cardiac patients with hemoglobin less than 10 g per dL (100 g per L). However, oral iron therapy is usually the first-line therapy for patients with IDA.
Taking supplements and eating iron-rich foods are important parts of treating IDA. However, you and your health care provider must first search for the cause of your anemia. Iron supplements (most often ferrous sulfate) are needed to build up the iron stores in your body. Patients who cannot take iron by mouth can take it through a vein (IV or intravenous) or by an injection into the muscle.
Pregnant and breastfeeding women will need to take extra iron because their normal diet usually will not provide the amount they need.
NOTE: The above information is educational purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.