Iron deficiency anaemia

Iron Deficiency Anaemia Dr. Zina Adnan MB,Ch.B , FICP

Iron deficiency is the commonest cause of anemia throughout the world. as the body has a limited ability to absorb iron, only 5 – 10 % of dietary iron is normally absorbed, this proportion can be increased to 20 – 30% in iron deficiency anaemia.

It is the most important cause of microcytic hypochromic anemia, in which all three red cell indices: MCV, MCH, MCHC are reduced.

Body Iron Distribution (Total Body Iron =( 3 – 4 g) Haemoglobin (65-70% ): contains about two third of body iron.

Plasma iron (<1%): is carried by a specialized protein called transferrin into developing erythroblasts in the bone marrow. Transferrin obtains iron mainly from reticulo-endothelial cells (macrophages).

Storage iron (20-25%): Some of the iron is stored in the reticulo-endothelial cells (RE cells) as haemosiderin and ferritin.

Myoglobin and enzymes of cell respiration (10%): Iron is also present in muscles as myoglobin and in most cells of the body in iron containing enzymes.

Dietary Iron: Meat and in particular liver is a better source of iron than vegetables, eggs or dairy foods.

Iron absorption:

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Occurs through the duodenum and less through the jejunum.

Excretion of Iron: Losses of iron occur through: •

1. Shedding of intestinal cells and macrophages in stool.

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2. Urine.

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3. Nails, hair and desquamated skin cells.

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4. Menstruation in females.

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Total losses of Iron/day ~ 1 mg is counterbalanced by a daily absorption of ~ 1 mg from diet.

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Causes of Iron Deficiency (1). BLOOD LOSS: (a). Uterine (b). Gastrointestinal (c). Renal tract (d). Pulmonary tract ... (e). Widespread bleeding disorder (2). Increased Iron Requirement: In children under age of 3 and in pregnancy (3). MALABSORPTION: Celiac Disease / Gluten Induced Gastrectomy; Atrophic Gastritis; Chronic Inflammation.

(4). DIETARY: Especially vegetable diet

Clinical features of iron deficiency anaemia 1- The patient may develops general symptoms and signs of anaemia: Pallor, dyspnea, weakness, lethargy, headache, palpitation.

2- Painless glossitis, Angular stomatitis, 3- Spoon nails (koilonychias), dysphagia.

4- Unusual dietary craving (Pica) ,like eating uncooked rice , mud or ice .

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Pallor

Glossitis

Koilonychia (Spooning of the nails)

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Laboratory Findings - Blood film shows hypochromic, microcytic cells with occasional target cells and pencil-shaped poikilocytes.

- The reticulocyte count is low.

- The red cell indices all are reduced including the mean cell volume (MCV), mean cell haemoglobin (MCH) and mean cell haemoglobin concentration (MCHC).

- Platelets count is often raised - Decreased serum iron and increased total iron binding capacity transferrin saturation is low (<15 %).

- Decreased serum ferritin as the iron stores are depleted.

Blood Film findings in IDA: Normochromic, normocytic

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Hypochromic, Microcytic

Treatment 1. Treatment of the underlying cause.

2. Correction of the deficiency by therapy with inorganic iron.

ORAL IRON THERAPY 100 to 200 mg of iron should be prescribed daily to adult patients and about 1 mg/kg t.i.d as liquid iron for children.

Response to Iron therapy â&#x20AC;˘

An increase in Retics will start by 4th day and reaches maximum in 7-10 days.

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The Hb will increase by an average of 0.15-0.2 g/dl per day.

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Should continue therapy for another 3 months after Hb returns to normal to replenish stores.

Failure of response to oral iron therapy : (1). Continued hemorrhage (2). Intolerance to oral iron.

(3). Malabsorption.

(4). Incorrect diagnosis.

PARENTERAL IRON THERAPY Parenteral iron may be given in the following situations:(1). Iron intolerance.

(2). Gastrointestinal disorders like ulcerative colitis or Crohn's disease.

(3). Celiac disease (occasionally).

(4). When it is essential to replete body stores rapidly, as in severe anemia diagnosed first in late pregnancy or just before an operative procedure, or when oral iron cannot keep pace with continuing hemorrhage.

Conclusion •

Iron deficiency is the commonest cause of anemia.

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Bleeding is the commonest cause of IDA

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The RBCs are hypochromic microcytic.

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Koilonychia and dysphagia are specific signs of iron deficiency anemia.

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Treatment include treating the underlying cause and iron replacement therapy.

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