Iron deficiency anemia: Difference between revisions

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imported>Aleksander Stos
m (untag cz_live (upon checking history of edits))
imported>Robert Badgett
(This article had no references - now does. Still has lots of disputable/unsupported statements that were copy/pasted from WP)
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*[[Tinnitus]]
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*Seeing Bright Colors{{fact}}
*[[Fainting]], Feeling faint
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*[[Depression (mood)|Depression]]
*[[Depression (mood)|Depression]]{{fact}}
*[[Weakness]]
*[[Weakness]]
*[[Breathlessness]]
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* Cognitive dysfunction<ref name="pmid17344500">{{cite journal |author=Murray-Kolb LE, Beard JL |title=Iron treatment normalizes cognitive functioning in young women |journal=Am. J. Clin. Nutr. |volume=85 |issue=3 |pages=778–87 |year=2007 |pmid=17344500 |doi=}}</ref>
*[[Twitching]] [[Nerves]], [[Tingling]], [[Numbness]]
*[[Twitching]] [[Nerves]], [[Tingling]], [[Numbness]]
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Anemia will be diagnosed on the basis of suggestive symptoms, or found on the basis of routine testing, which includes a [[complete blood count]] (CBC). A sufficiently low [[hemoglobin]] or [[hematocrit]] value is diagnostic of anemia, and further studies will be undertaken to determine its cause. One of the first abnormal values to be noted on a CBC will be a high [[red blood cell distribution width]] (RDW), reflecting a varied population of [[erythrocytes|red blood cells]]. A low [[Mean corpuscular volume|MCV]], [[Mean corpuscular hemoglobin|MCH]] or [[Mean corpuscular hemoglobin concentration|MCHC]], and the appearance of the RBCs on visual examination of a [[peripheral blood smear]] will narrow the diagnosis to a ''microcytic anemia''.
Anemia will be diagnosed on the basis of suggestive symptoms, or found on the basis of routine testing, which includes a [[complete blood count]] (CBC). A sufficiently low [[hemoglobin]] or [[hematocrit]] value is diagnostic of anemia, and further studies will be undertaken to determine its cause. One of the first abnormal values to be noted on a CBC will be a high [[red blood cell distribution width]] (RDW), reflecting a varied population of [[erythrocytes|red blood cells]]. A low [[Mean corpuscular volume|MCV]], [[Mean corpuscular hemoglobin|MCH]] or [[Mean corpuscular hemoglobin concentration|MCHC]], and the appearance of the RBCs on visual examination of a [[peripheral blood smear]] will narrow the diagnosis to a ''microcytic anemia''.


The diagnosis of iron deficiency anemia will be suggested by appropriate history (e.g., anemia in a menstruating woman), and by such diagnostic tests as a low serum [[ferritin]], a low serum [[iron]] level, an elevated serum [[transferrin]] and a high [[total iron binding capacity]] (TIBC). A definitive diagnosis requires a demonstration of depleted body iron stores by performing a [[bone marrow]] [[Needle aspiration biopsy|aspiration]], with the marrow stained for iron.  Because this is invasive and painful, while a [[clinical trial]] of iron supplementation is inexpensive and non-traumatic, patients are often treated without a definitive diagnosis.  
===Evaluation of iron status===
The serum [[ferritin]] is the most [[sensitivity (tests)|sensitive]] lab test for [[iron deficiency anemia]].<ref>{{cite journal | author = Guyatt G, Patterson C, Ali M, Singer J, Levine M, Turpie I, Meyer R | title = Diagnosis of iron-deficiency anemia in the elderly. | journal = Am J Med | volume = 88 | issue = 3 | pages = 205-9 | year = 1990 | id = PMID 2178409}}</ref> Other tests include a low serum [[iron]] level, an elevated serum [[transferrin]] and a high [[total iron binding capacity]] (TIBC). A definitive diagnosis requires a demonstration of depleted body iron stores by performing a [[bone marrow]] [[Needle aspiration biopsy|aspiration]], with the marrow stained for iron.  Because this is invasive and painful, while a [[clinical trial]] of iron supplementation is inexpensive and non-traumatic, patients are often treated without a definitive diagnosis.  


The diagnosis of iron deficiency anemia requires further investigation as to its cause. It can be a sign of other disease, such as [[colon cancer]], which will cause the loss of blood in the [[stool]]. In addition to dietary insufficiency, malabsorption, chronic blood loss, diversion of iron to fetal [[erythropoiesis]] during pregnancy, intravascular [[hemolysis]] and [[hemoglobinuria]] or other forms of chronic blood loss should all be considered.
===Evaluation of underlying causes===
The diagnosis of iron deficiency anemia requires further investigation as to its cause. In adults, 60% of patients with iron deficiency anemia may have underlying gastrointestinal disorders leading to chronic fecal blood loss.<ref name="pmid8179652">{{cite journal |author=Rockey D, Cello J |title=Evaluation of the gastrointestinal tract in patients with iron-deficiency anemia |journal=N Engl J Med |volume=329 |issue=23 |pages=1691-5 |year=1993 |id=PMID 8179652}}</ref> Other gastrointestinal causes include malaborption and [[celiac disease]]. Additional causes are dietary insufficiency, menstruation, diversion of iron to fetal [[erythropoiesis]] during pregnancy, intravascular [[hemolysis]] and [[hemoglobinuria]] or other forms of chronic blood loss should all be considered.


==Treatment==
==Treatment==
If the cause is dietary iron deficiency, [[iron supplements]], usually with [[iron (II) sulfate]] or iron amino acid chelate, can correct the anemia.  Chelated iron, while not as widely known as iron sulfate, is ten to fifteen times more bioavailable per mg and has none of the side effects of iron sulfate's sulfur content.  Iron supplements must be kept out of the reach of children, as iron-containing supplements are a frequent cause of poisoning in the pediatric age group. If malabsorption is present, it may be necessary to administer iron [[parenteral|parenterally]] (e.g., as iron [[dextran]]).  Parenteral iron other than in chelated form, however, is generally poorly tolerated.
If the cause is dietary iron deficiency, [[iron supplements]], usually with [[iron (II) sulfate]] or iron amino acid chelate, can correct the anemia.  Chelated iron, while not as widely known as iron sulfate, is ten to fifteen times more bioavailable per mg and has none of the side effects of iron sulfate's sulfur content.  Iron supplements must be kept out of the reach of children, as iron-containing supplements are a frequent cause of poisoning in the pediatric age group. If malabsorption is present, it may be necessary to administer iron [[parenteral|parenterally]] (e.g., as iron [[dextran]]).  Parenteral iron other than in chelated form, however, is generally poorly tolerated.


Follow up evaluation with retesting of [[hemoglobin]] and [[hematocrit]] is essential to demonstrate whether the treatment has been effective.  Testing of the [[reticulocyte]] count is another way physicians measure a response to iron therapy in iron deficiency.  Finally, ongoing testing of iron indices via the [[ferritin]] levels, [[TIBC]], and [[serum iron]] levels are imperative to avoid iron overloading.
The replacement dose of iron, at least in the elderly, may be as little as 15 mg per day of elemental iron <ref name="pmid16194646">{{cite journal |author=Rimon E, Kagansky N, Kagansky M, Mechnick L, Mashiah T, Namir M, Levy S |title=Are we giving too much iron? Low-dose iron therapy is effective in octogenarians |journal=Am J Med |volume=118 |issue=10 |pages=1142-7 |year=2005 |id=PMID 16194646 | doi = 10.1016/j.amjmed.2005.01.065}}</ref>.
 
Follow up evaluation with retesting of the [[hemoglobin]][[hematocrit]], and mean corpuscular volume may help demonstrate whether the treatment has been effective.  Testing of the [[reticulocyte]] count is another way physicians measure a response to iron therapy in iron deficiency.  Finally, ongoing testing of iron indices via the [[ferritin]] level and maybe [[TIBC]], and [[serum iron]] levels are imperative to avoid iron overloading.
 
==References==
<references/>


==See Also==
==See Also==

Revision as of 06:27, 18 October 2007

Iron deficiency anemia
Redbloodcells.jpg

Red blood cells
ICD-10 ICD10 F84.0-F84.1
ICD-9 280
MeSH D018798

Iron deficiency anemia is the most common type of anemia, and the most common cause of microcytic anemia.

Iron deficiency anemia occurs when the dietary intake or absorption of iron is insufficient, and hemoglobin, which contains iron, cannot be formed. In the United States, 20% of all women of childbearing age have iron deficiency anemia, compared with only 2% of adult men. The principal cause of iron deficiency anemia in premenopausal women is blood lost during menses.

Iron deficiency anemia is the final stage of iron deficiency. When the body has sufficient iron to meet its needs (functional iron), the remainder is stored for later use in the bone marrow, liver, and spleen. Iron deficiency ranges from iron depletion, which yields little physiological damage, to iron deficiency anemia, which can affect the function of numerous organ systems. Iron depletion causes the amount of stored iron to be reduced, but has no effect on the functional iron. However, a person with no stored iron has no reserves to use if the body requires more iron. In essence, the amount of iron absorbed by the body is not adequate for growth and development or to replace the amount lost.

History

A disease believed to be iron deficiency anemia is described in about 1500 B.C. in the Egyptian Ebers papyrus. It was termed chlorosis or green sickness in Medieval Europe, and iron salts were used for treatment in France by the mid-17th century. Thomas Sydenham recommended iron salts as treatment for chlorosis, but treatment with iron was controversial until the 20th century, when its mechanism of action was more fully elucidated.

Symptoms

Iron deficiency anemia is characterized by pallor, fatigue and weakness. Because it tends to develop slowly, adaptation occurs and the disease often goes unrecognized for some time. In severe cases, dyspnea can occur. Unusual obsessive food cravings, known as pica, may develop.

Hair loss and lightheadedness can also be associated with iron deficiency anemia.

Other symptoms

Other symptoms patients with iron deficiency anemia have reported are:

Diagnosis

Anemia will be diagnosed on the basis of suggestive symptoms, or found on the basis of routine testing, which includes a complete blood count (CBC). A sufficiently low hemoglobin or hematocrit value is diagnostic of anemia, and further studies will be undertaken to determine its cause. One of the first abnormal values to be noted on a CBC will be a high red blood cell distribution width (RDW), reflecting a varied population of red blood cells. A low MCV, MCH or MCHC, and the appearance of the RBCs on visual examination of a peripheral blood smear will narrow the diagnosis to a microcytic anemia.

Evaluation of iron status

The serum ferritin is the most sensitive lab test for iron deficiency anemia.[2] Other tests include a low serum iron level, an elevated serum transferrin and a high total iron binding capacity (TIBC). A definitive diagnosis requires a demonstration of depleted body iron stores by performing a bone marrow aspiration, with the marrow stained for iron. Because this is invasive and painful, while a clinical trial of iron supplementation is inexpensive and non-traumatic, patients are often treated without a definitive diagnosis.

Evaluation of underlying causes

The diagnosis of iron deficiency anemia requires further investigation as to its cause. In adults, 60% of patients with iron deficiency anemia may have underlying gastrointestinal disorders leading to chronic fecal blood loss.[3] Other gastrointestinal causes include malaborption and celiac disease. Additional causes are dietary insufficiency, menstruation, diversion of iron to fetal erythropoiesis during pregnancy, intravascular hemolysis and hemoglobinuria or other forms of chronic blood loss should all be considered.

Treatment

If the cause is dietary iron deficiency, iron supplements, usually with iron (II) sulfate or iron amino acid chelate, can correct the anemia. Chelated iron, while not as widely known as iron sulfate, is ten to fifteen times more bioavailable per mg and has none of the side effects of iron sulfate's sulfur content. Iron supplements must be kept out of the reach of children, as iron-containing supplements are a frequent cause of poisoning in the pediatric age group. If malabsorption is present, it may be necessary to administer iron parenterally (e.g., as iron dextran). Parenteral iron other than in chelated form, however, is generally poorly tolerated.

The replacement dose of iron, at least in the elderly, may be as little as 15 mg per day of elemental iron [4].

Follow up evaluation with retesting of the hemoglobin, hematocrit, and mean corpuscular volume may help demonstrate whether the treatment has been effective. Testing of the reticulocyte count is another way physicians measure a response to iron therapy in iron deficiency. Finally, ongoing testing of iron indices via the ferritin level and maybe TIBC, and serum iron levels are imperative to avoid iron overloading.

References

  1. Murray-Kolb LE, Beard JL (2007). "Iron treatment normalizes cognitive functioning in young women". Am. J. Clin. Nutr. 85 (3): 778–87. PMID 17344500[e]
  2. Guyatt G, Patterson C, Ali M, Singer J, Levine M, Turpie I, Meyer R (1990). "Diagnosis of iron-deficiency anemia in the elderly.". Am J Med 88 (3): 205-9. PMID 2178409.
  3. Rockey D, Cello J (1993). "Evaluation of the gastrointestinal tract in patients with iron-deficiency anemia". N Engl J Med 329 (23): 1691-5. PMID 8179652.
  4. Rimon E, Kagansky N, Kagansky M, Mechnick L, Mashiah T, Namir M, Levy S (2005). "Are we giving too much iron? Low-dose iron therapy is effective in octogenarians". Am J Med 118 (10): 1142-7. DOI:10.1016/j.amjmed.2005.01.065. PMID 16194646. Research Blogging.

See Also

External links