nada mohamed ahmed, md, mt (ascp)i. definition. physiology of iron. causes of iron deficiency. at...

Iron Deficiency Anemia

Nada Mohamed Ahmed ,MD, MT (ASCP)i

• Definition .• Physiology of iron. • Causes of iron deficiency.• At risk group .• Stages of IDA (pathophysiology).• Symptoms (clinical presentation ).• Lab diagnosis.

LEARNING OBJECTIVES

Definition Iron Deficiency Anemia

• Iron deficiency anemia is a condition in which hemoglobin synthesis has been defected due to reduce or lacking of iron in the body .

• Iron is an essential mineral that is needed to form hemoglobin( an oxygen carrying protein inside red blood cells).

• Iron is vital for all living organisms because it is essential for multiple metabolic processes, including oxygen transport, DNA synthesis, and electron transport

Physiology of iron:

• 1- distribution of iron • 2- source of iron • 3-Iron absorption • 4-Iron transport• 5-storage of iron

) Distribution (of iron in human body

Distribution:

Synthesis hemoglobin 64%

Synthesis myoglobin 3.2%

Ferritin 32%

Hemosiderin (stored in bone marrow ,liver, spleen.)

The iron-containing Enzymes 0.4%

Transferring 0.4%

Absorption

• Iron Taken up as ionic iron or haem iron Ferrous, Fe2+, most soluble = most absorbable

•10% of the 10 to 20 mg of dietary iron is absorbed each day to balance the 1 to 2 mg daily loss.

•Iron is absorbed in Duodenum& Jejunum.

•Stored as Ferritin & Hemosiderin.

INHIBITORS OF IRON ABSORPTION

Food with polyphenol compoundsVegetables such as spinach and spices Beverages like tea, coffee, cocoa and wine. A single cup of tea taken with meal reduces iron absorption by up to 11%.

IRON TRANSPORT

Red cells

As haemoglobinCannot be exchanged

PlasmaBound to TransferrinCarries iron between body locationse.g between gut, liver, bone marrow, macrophagesIron taken up into cells by transferrin receptors

STORAGE OF IRON

Tissues with higher requirement for iron ( bone marrow, liver & placenta) contain more

transferrin receptors.

Once in tissues, iron is stored as ferritin & hemosiderin compounds, which are present in the liver & bone marrow.

Causes of iron deficiency

1-Increased blood loss – hemorrhage(menorrhagia, chronic gastrointestinal blood loss)

2-Increased requirementspregnancy, children (growth)

3-Poor dietary intake ( Malabsorption)

AT RISK GROUPS

Infants Under 5 childrenChildren of school ageWomen of child bearing age

• 1-Iron deficiency anemia is the most common form of anemia and it develops over time if the body does not have enough iron to synthesize red blood cells.

• 2-Without enough iron, the body uses up all the iron it has stored in the liver, bone marrow and other organs.

Stages of IDA (pathophysiology)

• 3-Once the stored iron is depleted, the body is able to make very few red blood cells.

• 4-If erythropoietin is present without sufficient iron, there is insufficient fuel for red blood cell production

• 5-The red blood cells that the body is able to make are abnormal and do not have a normal hemoglobin-carrying capacity, as do normal red blood cells.

Clinical Presentation(Symptoms )

• Iron-deficiency anemia can cause:brittle nails

cracks in the sides of the mouth

Extreme fatigue (tiredness)

chest pain

• Pale skin

• Dizziness or lightheadedness

• Fast heart rate

• Headache

General Symptoms (clinical presentation ).

an enlarged spleenCold hands and feetfrequent infections.Irritabilityshortness of breathswelling or soreness of the tongue

Lab Diagnosis in IDA

Complete blood count(Microcytic hypochromic) anaemiaLow Hb level (< 11.0 g/dl)Low MCV, MCH, MCHCLow serum ferritin

High Transferrin (Iron Binding Capacity)

Iron Deficiency Anemia

Iron Deficiency AnemiaNormal blood film