Iron deficiency anemia is a common type of anemia- a condition in which blood lacks adequate healthy red blood cells. Iron deficiency is defined as decreased total iron body content. Iron deficiency anemia occurs when iron deficiency is sufficiently severe to diminish erythropoiesis and cause the development of anemia.

Causes

Lack of iron in diet

• If you consume too little iron, over time your body can become iron deficient. Examples of iron-rich foods include meat, eggs, dairy products or iron-fortified foods.
• Substances that diminish the absorption of ferrous and ferric iron are phytates, oxalates, phosphates, carbonates, and tannates.
• Similarly, ascorbic acid increases the absorption of ferric and ferrous iron and has little effect upon the absorption of heme iron.

Blood loss

• Women with heavy periods are at risk of iron deficiency anemia because they lose a lot of blood during menstruation.
• Slow, chronic blood loss within the body — such as from a peptic ulcer, a kidney or bladder tumor, a colon polyp, colorectal cancer, or uterine fibroids — can cause iron deficiency anemia.
• Gastrointestinal bleeding can result from regular use of aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs).

Malabsorption of iron

• Prolonged achlorhydria may produce iron deficiency because acidic conditions are required to release ferric iron from food.
• An intestinal disorder, such as Crohn's disease or celiac disease, which affects your intestine's ability to absorb nutrients from digested food, can lead to iron deficiency anemia.
•  If part of your small intestine has been bypassed or removed surgically, that may affect your ability to absorb iron and other nutrients.

Increased demand of iron

• Pregnancy and lactation
• Adolescent and puberty

Intestinal parasites

Hook worm, fish tape worm

Risk factors

• Women- increased demand during pregnancy and lactation, Heavy menstrual periods
• Infants and children
• Infants, especially those who were low birth weight or born prematurely, who don't get enough iron from breast milk or formula may be at risk of iron deficiency.
• Children need extra iron during growth spurts, because iron is important for muscle development.
• Vegetarians- Because vegetarians don't eat meat, they're at greater risk of iron deficiency anemia.

Signs and symptoms

• Extreme fatigue
• Pale skin
• Weakness
• Shortness of breath
• Headache
• Dizziness or lightheadedness
• Cold hands and feet
• Irritability
• Inflammation or soreness of your tongue
• Increased likelihood of infections
• Brittle nails
• Irregular heartbeat (arrhythmia)
• Unusual cravings for non-nutritive substances, such as ice, dirt or pure starch
• Poor appetite, especially in infants and children with iron deficiency anemia
• Restless legs syndrome — an uncomfortable tingling or crawling feeling in your legs

Complications

• Cardiac disease- In people with coronary artery disease — narrowing of the arteries that supply the heart — unchecked anemia can lead to angina.
• Problems during pregnancy- In pregnant women, severe iron deficiency anemia has been linked to premature births and low birth weight babies
• Growth problems- In infants and children, severe iron deficiency can lead to anemia as well as delayed growth.

Differential diagnosis

• Lead poisoning
• Anemia due to chronic disease
• Sideroblastic anemia
• Thallesemia

Tests and diagnosis

• In iron deficiency anemia, the cellular indices shows a microcytic and hypochromic erythropoiesis, ie, both the mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) have values below the normal range
• Platelet count is elevated
• A low serum iron and ferritin with an elevated TIBC are diagnostic of iron deficiency.
• A bone marrow aspirate can be diagnostic of iron deficiency
• Testing stool for the presence of hemoglobin is useful in establishing gastrointestinal bleeding as the etiology of iron deficiency anemia.

Additional diagnostic tests

• Endoscopy- To rule out
• Colonoscopy- To rule out lower intestinal sources of bleeding
• Ultrasound- Women may also have a pelvic ultrasound to look for the cause of excess menstrual bleeding, such as uterine fibroids.

Treatment

Diet

• On a worldwide basis, diet is the major cause of iron deficiency.
• Iron-rich foods includes meat, egg, green leafy vegetables, jaggery, beans, peas, nuts, dried fruits and poultry products

Iron supplementation

• Ferrous sulphate
• Mainstay treatment for treating patients with iron deficiency anemia
• They should be continued for about 2 months after correction of the anemia and its etiological cause in order to replenish body stores of iron.
• Ferrous sulfate is the most common and cheapest form of iron utilized. Tablets contain 50-60 mg of iron salt.
• These oral iron supplements are usually best absorbed from an otherwise empty stomach.
• However, because iron can irritate your stomach, you may need to take the supplements with food. Your doctor may recommend that you take iron supplements with orange juice or with a vitamin C tablet.
•  Vitamin C helps increase iron absorption.
• Additionally, take iron supplements two hours before or four hours after taking an antacid, as these medications can interfere with iron absorption.
• Iron supplements can cause constipation, so your doctor may also recommend a stool softener.
• Iron almost always turns stools black, which is a harmless side effect.

Dextran iron- parental

0.5 mL IV/IM (slowly over 1 min if IV); observe for 60 min before providing additional medication

Usual adult dose: 2 mL/d (100 mg iron); may be given until anemia is corrected

Blood transfusion

When iron deficiency is due to blood loss, and HB levels are very low then need of packed transfusion is required.

Prognosis

• Iron deficiency anemia is an easily treated disorder with an excellent outcome; however, it may be caused by an underlying condition with a poor prognosis, such as neoplasia.
• Similarly, the prognosis may be altered by a comorbid condition such as coronary artery disease.