Iron deficiency anemia is often asymptomatic. Signs and symptoms are non-specific, unless the anemia is severe. Fatigue is the most common symptom [6]. Patients may complain of [1] [3] [8]:

• Fatigue
• Pallor
• Weakness
• Headache
• Palpitations
• Dizziness
• Dyspnea
• Irritability
• Poor concentration, impaired development 
• Hair loss
• Impaired temperature regulation
• Decreased resistance to infection
• Worsened cardiac or pulmonary symptoms [1]

Physical findings [5] [6]:

• Impaired growth and development in children [5] [8]
• Pallor of the mucous membranes
• Spoon-shaped nails with decreased capillary refill
• Angular stomatitis
• Splenomegaly in severe, persistent, anemia
• Decreased physical functioning, and mobility, diminished muscle strength
• Cardiovascular complications

• Anemia

  Subjects were divided into three groups according to hemoglobin levels and bone marrow iron staining results: the IDA (iron deficiency anemia) group, the NIDA (non-iron deficiency anemia) group, and the control group. [ncbi.nlm.nih.gov]

• Fatigue

  Signs and Symptoms of Anemia The most common symptom of all types of anemia is fatigue (tiredness). Fatigue occurs because your body doesn't have enough red blood cells to carry oxygen to its many parts. [web.archive.org]

  A 19-month-old girl with a history of asthma and atopic dermatitis presented to her pediatrician because of parental concerns of pallor and fatigue. [ncbi.nlm.nih.gov]

  Mental fatigue can manifest as somnolence, lethargy, or directed attention fatigue.[4] Fatigue and 'feelings of fatigue' are sometimes confused.[5] Unlike weakness, fatigue usually can be alleviated by periods of rest. [en.wikipedia.org]

• Weakness

  Iron deficiency anemia is the most common type of anemia You may look pale and feel weak and short of breath The most common cause of low iron is bleeding Doctors measure your iron levels with blood tests Doctors treat iron deficiency anemia with iron [msdmanuals.com]

  Here, we report a case of an 82-year-old man with a history of cerebrovascular disease presented with weakness and iron deficiency anemia. He denied any abdominal discomforts. [ncbi.nlm.nih.gov]

  Anemia also can cause shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, chest pain, weakness, and fatigue (tiredness). [web.archive.org]

• Pallor

  A 19-month-old girl with a history of asthma and atopic dermatitis presented to her pediatrician because of parental concerns of pallor and fatigue. [ncbi.nlm.nih.gov]

  Data show that pallor (p = 0.0003), pica (p = 0.004) and pallor and pica (p = 0.00015) together were significantly associated with anemia. [web.archive.org]

• Asymptomatic

  Asymptomatic Children aged 6 to 12 Months The U.S. Preventive Services Task Force (USPSTF) concludes that evidence is insufficient to recommend for or against routine screening for iron deficiency anemia in asymptomatic children aged 6 to 12 months. [uspreventiveservicestaskforce.org]

  Abstract The US Preventive Services Task Force (USPSTF) makes recommendations to primary care providers regarding preventive services for asymptomatic patients. [ncbi.nlm.nih.gov]

  POPULATION: This recommendation applies to children ages 6 to 24 months living in the United States who are asymptomatic for iron deficiency anemia. [pediatrics.aappublications.org]

• Dyspnea

  Shortness of breath Other names Dyspnea, dyspnoea, breathlessness, difficulty of breathing, respiratory distress Pronunciation Dyspnea: /dɪspˈniːə/ Specialty Pulmonology Shortness of breath (SOB), also known as dyspnea, is a feeling of not being able [en.wikipedia.org]

  […] bleeding, such as from an ulcer or a polyp in the intestines Iron deficiency anemia symptoms Call your primary care doctor to schedule an appointment if you have any of the following symptoms and they don’t go away: Fatigue Dizziness Shortness of breath (dyspnea [rush.edu]

  Treatment Transfusion should be considered for patients of any age with IDA complaining of symptoms such as fatigue or dyspnea on exertion. [aafp.org]

• Exertional Dyspnea

  Distinct sensations include effort/work, chest tightness, and air hunger (the feeling of not enough oxygen).[1] Dyspnea is a normal symptom of heavy exertion but becomes pathological if it occurs in unexpected situations[2] or light exertion. [en.wikipedia.org]

• Dysphagia

  It has been shown that iron deficiency can precede dysphagia [ 39 ]. [ojrd.com]

  Codes D50 Iron deficiency anemia D50.0 Iron deficiency anemia secondary to blood loss (chronic) D50.1 Sideropenic dysphagia D50.8 Other iron deficiency anemias D50.9 Iron deficiency anemia, unspecified [icd10data.com]

  […] hissing noises inside your head (tinnitus) food tasting strange feeling itchy a sore tongue hair loss – you notice more hair coming out when brushing or washing it wanting to eat non-food items, such as paper or ice (pica) finding it hard to swallow (dysphagia [nhs.uk]

  […] deficiency (Not in USA) Malabsorption (Sprue, gatrectomy) Rare causes Hemoglobinuria Hereditary hemorrhagic telengiectasia (Nose bleeds, GI bleeds) Clinical sequelae to iron deficiency anemia Asymptomatic until late Pica Angulostomatitis Koilonychias Fatigue Dysphagia [meddean.luc.edu]

• Loss of Appetite

  Some soil-transmitted helminths also cause loss of appetite and, therefore, a reduction of nutritional intake and physical fitness. In particular, T. trichiura can cause diarrhoea and dysentery. [who.int]

  Some soil-transmitted helminths also cause loss of appetite and therefore a reduction of nutritional intake and physical fitness. In particular, T. trichiura can cause diarrhoea and dysentery. [web.archive.org]

  People with colon or rectal cancer may have weight loss, fatigue (excessive weakness), loss of appetite, and a family history of cancer. Everyone over the age of 50 should be screened with a sigmoidoscopy. [chemocare.com]

  Gastrointestinal (GI) tract symptoms may include constipation, chronic or acute abdominal pain that may be diffuse or focused, nausea and vomiting, abdominal distention, and loss of appetite. [emedicine.com]

  Assessment History Inquire about recent weight loss, fatigue, weakness, dizziness, irritability, inability to concentrate, sensitivity to cold, heartburn, loss of appetite, diarrhea, or flatulence. [medical-dictionary.thefreedictionary.com]

• Geophagia

  We report a case of a 14-year-old boy who presented with iron deficiency anemia, hepatosplenomegaly, geophagia and growth retardation with pubertal delay. Investigations ruled out hypopituitarism and coeliac disease. [ncbi.nlm.nih.gov]

  In particular, geophagia (soil or clay ingestion) has been associated with soil-borne parasitic infections (eg, toxoplasmosis and toxocariasis ). [emedicine.com]

  Geophagia in Turkey: Iron and zinc deficiency, iron and zinc absorption studies and response to treatment with zinc in geophagia cases. In: Zinc Deficiency in Human Subjects. Eds. Prasad AS, Cavdar AO, Brewer GJ, Aggett PJ. [web.archive.org]

• Tachycardia

  Iron deficiency anemia may be suspected from general findings on a complete medical history and physical examination of your child, such as complaints of tiring easily, pale skin and lips, or a fast heartbeat (tachycardia). [nationwidechildrens.org]

  Iron-deficiency anemia may be suspected from general findings on a complete medical history and physical examination, such as complaints of tiring easily, abnormal paleness or lack of color of the skin, or a fast heartbeat (tachycardia). [hopkinsmedicine.org]

  Iron deficiency anemia may be suspected from general findings on a complete medical history and physical examination of your child, such as complaints of tiring easily, pale skin and lips or a fast heartbeat (tachycardia). [chw.org]

• Heart Murmur

  This can lead to irregular heartbeats called arrhythmias (ah-RITH-me-ahs), a heart murmur, an enlarged heart, or even heart failure. [web.archive.org]

  At that point, symptoms may include: tiredness and weakness pale skin, especially around the hands, nails, and eyelids rapid heartbeat or a heart murmur irritability low appetite dizziness or feeling lightheaded In rare cases, a child with iron-deficiency [rchsd.org]

  Some common symptoms associated with iron deficiency anemia include: Weakness and feeling tired Pale skin, especially around the hands, nails, and eyelids Fast heartbeat or a heart murmur Fast breathing Irritability Poor appetite Lightheadedness or dizziness [mottchildren.org]

  When your heart has to work harder, this can lead to several conditions: irregular heartbeats called arrhythmias, a heart murmur, an enlarged heart, or even heart failure. [nhlbi.nih.gov]

• Palpitations

  Return to Play Athletes with symptoms like weakness, shortness of breath, or heart palpitations will likely have difficulty in competition, and exercise restriction may be considered until the athlete feels better. [sportsmedtoday.com]

  Symptoms may include: Feeling weak or tired more often than usual, or with exercise Headaches Dizziness Palpitations Problems concentrating or thinking As the anemia gets worse, symptoms may include: Brittle nails Blue color to the whites of the eye Desire [nlm.nih.gov]

  Check if you have iron deficiency anaemia Symptoms can include: tiredness and lack of energy shortness of breath noticeable heartbeats (heart palpitations) pale skin Less common symptoms of iron deficiency anaemia Less common symptoms of iron deficiency [nhs.uk]

• Hypotension

  Analyzed safety concerns include gastrointestinal side effects (oral iron) and risks of hypotension, anaphylaxis, infection, hypophosphatemia, oxidative stress and mortality (IV iron). [ncbi.nlm.nih.gov]

  Some patients report a numb sensation in their head, and others have reported blurred vision caused by hypotension behind the eye due to a lack of oxygen and pressure; these patients have also reported severe head pains, many of which lead to permanent [en.wikipedia.org]

  All other adverse events were related to iron saccharate infusions: burning at the site of venipuncture (n = 3), bitter taste (n = 2), transient fever (n = 3), and transient hypotension (n = 2). [cochranelibrary.com]

• Cheilitis

  Symptoms of Iron Deficiency Anemia An iron deficiency anemia has the same symptoms than any other anemia: Image : “Angular cheilitis as marked by the oval” by James Heilman, MD. [lecturio.com]

  Additional features are glossitis, angular cheilitis and koilonychia. Enlargement of the spleen and thyroid may also be observed. [ojrd.com]

• Restless Legs Syndrome

  In adults, ID is associated with fatigue in the absence of anemia, restless legs syndrome, pica and, in neonates, delayed growth and development. In adolescents, ID is associated with decrements in learning and behavioral abnormalities. [ncbi.nlm.nih.gov]

  Some people who have iron-deficiency anemia develop restless legs syndrome (RLS). RLS is a disorder that causes a strong urge to move the legs. This urge to move often occurs with strange and unpleasant feelings in the legs. [web.archive.org]

  Restless leg syndrome is associated with iron deficiency anemia. Anemia can be classified as microcytic (low MCV; or mean corpuscular volume), normocytic (normal MCV) and macrocytic (High MCV). [youtube.com]

• Conjunctival Pallor

  Anterior segment examination in both eyes showed conjunctival pallor. Results of ophthalmoscopic examination and optical coherence tomography were consistent with macular preretinal hemorrhage in both eyes with macular star in the left eye. [ncbi.nlm.nih.gov]

  Hence, in areas where iron deficiency is so widespread as in the present study population (87% iron deficient), children presenting with pica or conjunctival pallor may be suspected to have anemia and intervention recommended. [web.archive.org]

  The relation of conjunctival pallor to the presence of anemia. J Gen Intern Med. 1997;12:102–6. 23. Cook JD. Diagnosis and management of iron-deficiency anaemia. Best Pract Res Clin Haematol. 2005;18:319–32. 24. [aafp.org]

• Blurred Vision

  Some patients report a numb sensation in their head, and others have reported blurred vision caused by hypotension behind the eye due to a lack of oxygen and pressure; these patients have also reported severe head pains, many of which lead to permanent [en.wikipedia.org]

• Koilonychia

  Nutritional deficiency (Not in USA) Malabsorption (Sprue, gatrectomy) Rare causes Hemoglobinuria Hereditary hemorrhagic telengiectasia (Nose bleeds, GI bleeds) Clinical sequelae to iron deficiency anemia Asymptomatic until late Pica Angulostomatitis Koilonychias [meddean.luc.edu]

  Additional features are glossitis, angular cheilitis and koilonychia. Enlargement of the spleen and thyroid may also be observed. [ojrd.com]

  Other symptoms of severe deficiency include glossitis, cheilosis, and concave nails (koilonychia). [merckmanuals.com]

• Pruritus

  Severe side effects other than allergic reactions are rare and include urticaria (hives), pruritus (itching), and muscle and joint pain. [hematology.org]

  In the iron sucrose group, there were 27 reported adverse events [common AEs only: hyperferritinaemia 1, rash 0 (however according to the text: rash, dermatitis and pruritus 2), headache 1, iron overload 3] of which two participants required withdrawal [cochranelibrary.com]

• Alopecia

  Celiac disease and alopecia areata: report of a new association. Gastroenterology 109, 1333–1337 (1995). 68. Bardella, M. T. et al. Alopecia areata and coeliac disease: no effect of a gluten-free diet on hair growth. [dx.doi.org]

• Thin Brittle Fingernails

  Thin, brittle fingernails. Less energy than normal. Problems growing and developing normally. Pica Another sign of iron deficiency anemia is called “pica.” Pica is eating things that are not food. [stjude.org]

• Headache

  Omeprazole Side Effects Patients taking omeprazole may experience common side effects such as stomach pain, diarrhea, constipation, gas, nausea, headache, vomiting and fever, according to PubMed. [livestrong.com]

  Anemia also can cause shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, chest pain, weakness, and fatigue (tiredness). [web.archive.org]

  But over time, if the condition worsens, women may become aware of headaches, dizziness or light-headedness, cold hands and feet, pale skin, shortness of breath, inflammation in the gums or tongue and even irritability. [healthscopemag.com]

  Some symptoms of IDA include fatigue, pale skin, weakness, poor appetite, headache, irritability, unusual food cravings, and impaired growth and development. [childrensmn.org]

• Dizziness

  You are dizzy or very tired. You have questions or concerns about your condition or care. Care Agreement You have the right to help plan your care. Learn about your health condition and how it may be treated. [drugs.com]

  This can lead to a variety of health problems including low energy, fatigue, dizziness, poor circulation, and more. This condition is called iron deficiency and can eventually lead to iron deficiency anemia (IDA). [fergon.com]

  Anemia also can cause shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, chest pain, weakness, and fatigue (tiredness). [web.archive.org]

  Published on May 18, 2011 Susan had symptoms including tiredness, poor skin tone, dizziness, and depression. Her doctor diagnosed her with iron-deficiency anemia. [youtube.com]

• Irritability

  Areca nut is considered the primary etiology along with other local irritants like capsaicin, pungent and spicy food, nutritional deficiency, defective iron metabolism, collagen metabolic disorder and genetic predisposition. [ncbi.nlm.nih.gov]

  Supplements can cause irritation of the stomach and cause stools to become black in color. Iron supplements should be taken on an empty stomach or with orange juice to increase absorption. [illinoiscancercare.com]

  Iron supplements can cause irritation of the stomach and discoloration of bowel movements. They should be taken on an empty stomach or with orange juice to increase absorption. [chop.edu]

  Iron supplements can cause irritation of the stomach and discoloration of bowel movements. They should be taken on an empty stomach or with orange juice to increase absorption. They are much more effective than dietary interventions alone. [nationwidechildrens.org]

  Iron supplements can cause irritation of the stomach and discoloration of bowel movements. They should be taken on an empty stomach, or with orange juice, to increase absorption. They are much more effective than dietary interventions alone. [hopkinsmedicine.org]

• Apathy

  But for 3.4 million Americans, being tired is one of a host of symptoms— including headaches, pale skin, rapid heartbeat, shortness of breath, not to mention apathy and irritability—that collectively point to “tired blood,” more accurately known as anemia [healthscopemag.com]

  In addition, children may experience apathy and failure to thrive, and macrocytic anemia is a common feature at all ages. Zinc Vegetarians are often considered to be at risk for zinc deficiency. [dx.doi.org]

• Somnolence

  Mental fatigue has also been shown to decrease physical performance.[4] It can manifest as somnolence, lethargy, or directed attention fatigue. [en.wikipedia.org]

Iron deficiency anemia is diagnosed by the presence of two or more abnormal indices: serum ferritin, transferrin saturation, erythrocyte protoporphyrin.

Initial laboratory testing should include [3] [6]

• Complete blood count (CBC)
• Red blood cell evaluation: hemoglobin, hematocrit, reticulocyte count
• Red blood cell indices: mean cell volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), Red blood cell distribution/width (RDW)
• White blood cell count with cell differential
• Platelet count
• Iron studies
• Serum iron
• Serum ferritin
• Total iron binding capacity (TIBC)
• Transferrin saturation percentage
• Reticulocyte count (immature RBC) count, a measure of erythropoietic activity 
• Cell morphology

Additional laboratory testing to identify comorbid conditions [3] [6]:

• Serum cobalamin (B-12) and folate levels 
• Hemoglobin electrophoresis
• Serum methylmalonic acid and homocysteine levels 
• C-reactive protein (CRP) or IL-6 assays, are nonspecific inflammatory markers
• Liver function tests
• Lead level
• Thyroid stimulating hormone (TSH) test 
• Serum creatinine and/or calculated glomerular filtration rate
• Complete metabolic panel and hemoglobin A-1-C 

Other procedures to further identify possible cause [3]:

• Fecal occult blood test 
• Endoscopy
• Electrocardiogram 
• Bone marrow aspiration

Serum ferritin is a glycoprotein that indicates available iron stores. It is the first test to become abnormal as iron deficiency begins to develop. It is the best test to assess the degree of iron deficiency as it is not affected by recent ingestion of iron [3].

• Microcytic Anemia

  We report our experience with an 11-year-old Japanese girl with hypochromic microcytic anemia, low serum iron, and high serum ferritin, with anemia that was refractory to the oral iron that was prescribed frequently from early childhood. [ncbi.nlm.nih.gov]

• Thrombocytopenia

  An adolescent male presented with recurrent episodes over several years of severe iron deficiency anemia and associated severe thrombocytopenia. [ncbi.nlm.nih.gov]

• Thrombocytosis

  OBJECTIVE: In order to inquire into the pathogenesis of increased platelet counts in peripheral blood of patients with iron deficiency anemia (IDA), the phenomenon of thrombocytosis was confirmed, and then the expression of tubulin within platelets from [ncbi.nlm.nih.gov]

• Iron Decreased

  The serum iron decreased, followed by an increase in the total iron-binding capacity. Gradual decreases in the red blood cell indices occurred, with maximal microcytosis and hypochromia present 120 days after bleeding. [emedicine.medscape.com]

• Normocytic Anemia

  Iron deficiency anemia (IDA) is the most common cause of anemia worldwide...It starts as normocytic anemia (normal MCV) and then shifts into microcytic anemia (low MCV). [youtube.com]

  Anemias can also be classified according to the morphologic characteristics of the erythrocytes, such as size ( microcytic, macrocytic, and normocytic anemias ) and color or hemoglobin concentration ( hypochromic anemia ). [medical-dictionary.thefreedictionary.com]

  The CBC at that time revealed normocytic anemia (hemoglobin, 8.5 g/ dL [85 g/L]; hematocrit, 15.5% [0.16]; and MCV, 84 μm 3 [84 fL]), and the serum ferritin level was decreased (9 ng/ dL [20 pmol/L]). [doi.org]

  (PA), we have studied 160 patients with autoimmune gastritis of whom 83 presented with IDA, 48 with normocytic anemia, and 29 with macrocytic anemia 46 ( Table 2 ). [bloodjournal.org]

The treatment of iron deficiency anemia involves a two-step approach; restoring iron stores [10] and treating the underlying etiology. Management of the causative disease process will usually improve hemoglobin levels [7].

Treatment depends on the level of iron deficiency and the severity of the anemia, as well as any underlying conditions.

• Oral ferrous iron salts, ferrous sulfate, is the first recommendation, because it is effective and safe. Recommended dosage is 100–200 mg elemental iron daily [3]. Once hemoglobin is normal iron therapy should continue for 3 months to replenish iron stores [3]. Combined iron and folic acid preparations may also be used [3]. 
• Oral iron should be taken on an empty stomach [3]. Nausea, constipation, and epigastric discomfort are possible adverse effects and may result in non-compliance in 21% of patients [12]. Preparations with lower iron content, slow-release, or enteric-coated forms may prevent these effects [3]. Intermittent iron administration, weekly or on alternate days, may decrease adverse effects. These appear to be as effective as daily dosing.
• Parenteral iron is effective, but should be reserved for patients who cannot tolerate or absorb oral preparations, or whose anemia does not respond to oral medication [3] [7].
• Transfusions with packed red blood cells should be used only in patients with acute bleeding, severe hypoxia, or coronary insufficiency [10]. Management of anemia in pregnancy may require transfusions to prevent maternal or fetal morbidity and mortality [3] [7]. 
• Erythropoiesis-stimulating agents may also be effective in the treatment of iron deficiency anemia of chronic disease [5]. However, these drugs are not without adverse effects, particularly thromboembolism [1] [7]. 
• Dietary interventions are necessary in all patients to supplement other forms of treatment.
• Iron absorption depends on the amount of iron in the diet, its bioavailability and physiological needs of the body [3] [10]. The main sources of dietary iron are red meats, fish and poultry [3]. Iron from meat (heme-iron) is absorbed more readily than other forms of iron. Meat also contains compounds that promotes better iron absorption [4]. But approximately 95% of iron in the diet comes from non-hem iron sources [4].

Other dietary recommendations:

• Vitamin C (ascorbic acid) aids iron absorption from non-hem sources [3]. The quality of the source influences this effect [9].
• Tannins in tea and coffee inhibits the absorption of iron when consumed with the iron source [3].

Treatment of iron deficiency anemia should also include patient education including [3]:

• Dietary information regarding iron intake and absorption.
• Need for iron supplements and ways to avoid adverse effects. 
• Benefits of Vitamin C.
• Signs and symptoms of worsening anemia.

Excess iron can be toxic, and can lead to cell death and organ damage. Therefore, iron supplementation needs to be carefully monitored [1].

Iron deficiency anemia is a disorder with a good outcome, but it may be caused by an underlying condition with a poor prognosis.

Iron deficiency anemia is defined as a hemoglobin level less than 11g/dL (not associated with hemoglobinopathies) [3] [8] [9].
Iron status can be classified as iron sufficient, iron depleted, or iron deficiency anemia [8].

Iron sufficiency indicates that iron supplies are sufficient to supply normal and atypical body requirements for hematopoiesis [9]. In iron depletion, the total stored iron, serum ferritin concentration, is decreased, but the amount of transport iron remains normal [4] [9]. In iron deficiency anemia both stored iron and transport iron are decreased [3]. Therefore, the amount of iron is insufficient to provide what is needed for normal function. This results in inadequate hemoglobin production [3] [8] [9].

Iron deficiency anemia may also be classified by the underlying cause of the disorder [4] [6] [9] [10]:

• Nutritional deficits
• Blood loss
• Malabsorption
• Metabolic dysfunctio
• Diabete
• Chronic renal disease
• Chronic heart disease

Chronic iron deficiency anemia is a common occurrence in the elderly [5] [6] and in chronic disease. Anemia in diabetes and chronic kidney disease is a result of the kidney‘s inability to produce erythropoietin in response to abnormally low hemoglobin [10].

The prevalence of iron deficiency anemia is affected by diet and socioeconomic factors. It is seen more frequently in those living in poverty [8]. It varies worldwide from 10% in developed nations to 50% in less developed societies [8].

Prevalence of iron deficiency anemia in the elderly increases with age from 8 % at age 65, 12% at age 75, and 23% at age 85+ [6].
The incidence of iron deficiency anemia is higher in men than in women in all age groups [6].

Studies have reported the prevalence of iron deficiency anemia in elderly African Americans to be 3 times higher than in Caucasians, Hispanics, and Asian Americans [6]. However, normal hemoglobin levels are lower in those of African descent, a factor that is not always taken into account [3].

Iron deficiency anemia occurs in almost one third of patients with congestive heart failure (CHF) and 10% to 20% of patients with coronary heart disease (CHD) [2].

Iron is necessary for the production of hemoglobin, myoglobin, and enzymes of cellular metabolism. Iron deficiency results in abnormal hemoglobin synthesis leading to reduced ability of the red blood cells to carry oxygen [5]. Iron is involved in the development of the central nervous system, immune system, endocrine system and cardiovascular system [2] [5].

Iron absorption is regulated to replace body losses. Hepcidin is the key regulator of iron absorption in the intestinal tract and the distribution from body stores [1] [8]. Hepcidin, produced in the liver, responds to iron levels and needs by activating ferroportin [1] [9]. Ferroportin is present on the surface of duodenal mucosal cells and facilitates iron absorption. Decreased levels of ferroportin inhibit the absorption of iron into the plasma [1].

Iron deficiency anemia of chronic disease is the result of reduced glomerular filtration rate, reduced plasma flow, impaired erythropoietin production, and hemodilution [5] [11]. These findings are associated with elevated levels of inflammatory cytokines which indicate an autoimmune inflammatory process [7] [11].

Iron is also important in the production of myoglobin and myelin in the brain [8]. Iron deficiency, therefore, affects neurotransmitter metabolism, interfering with psychomotor, intellectual, and emotional function. These effects are seen particularly in children, but may also be responsible for symptoms in the elderly [8].

Ways of preventing and treating iron deficiency anemia include [9]:

• Health education regarding diet and iron needs.
• Fiscal measures to fund prevention and treatment programs.
• Screening programs; early identification and treatment may prevent serious complications [3] [9].
• Fortified foods; infant formula, breads and cereals.
• Iron supplementation in pregnant women, at risk infants, and adults at risk [3].

Iron deficiency anemia is defined as a decrease in red blood cells (RBCs), hemoglobin, and/or red blood cell volume a result of insufficient iron [1]. Iron deficiency is a major public health concern and the most common nutritional deficiency, affecting more than 2 billion people worldwide [2] [3] [4]. Although it is more prevalent in underdeveloped countries, it is still a problem in developed nations [3] [5]. The World Health Organization defines anemia as a hemoglobin (Hgb) level less than 12-13 g/dL [6]. Approximately 50% of anemia is due to iron deficiency [3].

The causes of iron deficiency anemia include: Nutritional deficits, malabsorption, excessive blood loss, and chronic disease [4] [7]. The cause of anemia is determined by patient history, dietary history, and the indices of iron status [7].

Iron deficiency anemia increases with age and as a result of chronic diseases, such as chronic heart disease, diabetes, and chronic renal disease [7].

The effects and complications of iron deficiency anemia are significant. Iron deficiency may interfere with psychomotor development and cognitive function in children [8]. It may increase maternal and fetal morbidity and mortality. Iron deficiency anemia in the elderly and chronically ill decreases quality of life, independence, and productivity. It has an important economically impact by diminishing the individual’s ability to work and perform physical labor [2].

What is iron deficiency anemia?

Iron deficiency anemia refers to a lower than normal level of hemoglobin (the oxygen carrying part of the blood) as a result of insufficient amounts of iron to produce it.

What are the symptoms of iron deficiency anemia?

Mild to moderate iron deficiency anemia is often asymptomatic. The symptoms of iron deficiency anemia include:

• Fatigue, weakness
• Pallor
• Palpitations, dizziness, dyspnea
• Irritability, poor concentration, impaired development
• Decreased resistance to infection

What causes iron deficiency anemia?

Iron deficiency anemia is caused by a decreased intake or absorption of iron and/or an increased need for or loss of hemoglobin. Chronic diseases, such as diabetes, chronic renal disease, and chronic heart disease, may also contribute to iron deficiency anemia.

Who gets iron deficiency anemia?

Anyone, at any age, may develop iron deficiency anemia. Individuals living in poverty or in developing parts of the world, where malnutrition and poor health conditions abound, are at highest risk.

Also at high risk are:

• Women of child bearing age
• Pregnant women
• Infants and toddlers
• Adolescents
• The elderly
• Individuals with chronic disease

How is iron deficiency anemia diagnosed?

Iron deficiency anemia is diagnosed by simple blood tests and is often found with routine blood screening. It may be suspected by symptoms of fatigue and activity intolerance.

How is iron deficiency anemia treated?

Iron deficiency anemia is treated by increasing the intake and absorption of iron. This may be done by increasing the iron in the diet or by supplementing with iron medications. Treating any other underlying cause is also needed.

What are the complications of iron deficiency anemia?

There are many possible complications of iron deficiency anemia. Iron is essential for the production of hemoglobin and for proper development and functioning of the nervous system.
Iron deficiency anemia may cause:

• Increased maternal/fetal mortality and morbidity.
• Increased problems associated with heart and respiratory disease.
• Alterations in growth and development.
• Decreased quality of life of the elderly and chronically ill.

How can iron deficiency anemia be prevented?

Iron deficiency anemia can be prevented by a balanced diet containing sufficient iron, from meats and non-meat sources, folic acid, and Vitamins C and B-12. It may also be prevented by iron supplementation of those at risk for developing iron deficiency anemia. Complications of iron deficiency anemia may be prevented by early detection and treatment through routine screening.

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