Iron Deficiency Anemia occurs when iron levels are too low to support normal red blood cell production. It has various causes like bleeding, low dietary iron intake, or loss of iron in the urine. Symptoms include fatigue and pale skin. Investigations show low hemoglobin, ferritin and iron levels with microcytic red blood cells. Treatment involves oral or intravenous iron supplementation depending on severity. Complications can include impaired development in children or increased risk of falls in the elderly. Prevention focuses on consuming iron-rich foods and supplements. Differential diagnoses include thalassemia and anemia of chronic disease.
4. Normal physiology & structure of Hb
Globular protein contain Heme + Globin
Accounts for > 95% of protein in RBC
Main functions: transportation of respiratory gases. It carries ~ 98.5% of all O2
Concentration of Hb in the Blood: Measured as g/dl (grams per deciliter, or
per 100 ml)
Average values:
Male: 14-18 g/dl
Female: 12-16 g/dl
Infants: 14-20 g/dl
5. Haematological indices
Mean corpuscular volume (MCV): The average size of the red blood cells
expressed in femtoliters (fl).
Normal value: 80-95 femtoliters (10-15 liters) abbreviated fl.
- Macrocytic anemias– larger than normal cells
- Normocytic anemia (MCV = 80-95 fl) – cells are normal in volume.
- Microcytic anemias– cells are smaller than normal.
Mean corpuscular Hb (MCH):
The average amount of hemoglobin inside a RBC expressed in picograms (pg).
Normal value: 27-33 pg (10-12 gram)
- Normochromic
- Hypochromic
- Hyperchromic
7. Metabolism of iron
(Adapted from Bothwell TH,
Charlton RW, Cook JD, Finch
CA: In Iron Metabolism in Man.
Oxford, UK: Blackwell Scientific,
1979, p 24.)
10. Fate of Components of Heme
Source: Dr.Ahmed Alshafei Lecture
• Iron(Fe+3)
- transported in blood attached to transferrin protein
- stored in liver
* attached to ferritin or hemosiderin protein
- in bone marrow, iron is used for hemoglobin synthesis
• Biliverdin (green) is converted to bilirubin (yellow)
- bilirubin is secreted by liver into bile
* converted to urobilinogen then stercobilin (brown pigment in
feces) by bacteria of large intestine
* if urobilinogen is reabsorbed from intestines into blood is
converted to a yellow pigment, urobilin and excreted in urine
12. Definition of IDA
Anemia is defined as a reduction in the oxygen-carrying capacity of
the blood caused by a diminished erythrocyte mass.
Iron deficiency anemia develops when body stores of iron drop too low
to support normal red blood cell (RBC) production. Inadequate dietary
iron, iron absorption, bleeding, or loss of body iron in the urine may
be the cause.
HGB<13.5 g/dL (men) <12 (women)
HCT<41% (men) <36 (women)
a ferritin concentration of more than 100 ng/mL (100 mg/L)
effectively rules out iron deficiency, and a ferritin of less than 15
ng/mL (15 mg/L) rules in iron deficiency.
More common in women as a result of menstrual losses
14. RFs of IDA in Pregnancy
Pregnant with more than one child
Two pregnancies close together
Vomiting a lot because of morning sickness
Teenager who is pregnant
Not enough foods that are rich in iron
Heavy periods before pregnancy
Source : http://www.webmd.com/baby/guide/anemia-in-pregnancy
19. S & S
Symptoms of anemia (eg, easy fatigability, tachycardia,
palpitations and tachypnea on exertion)
Skin and mucosal changes (eg, smooth tongue, brittle
nails, spooning of nails [koilonychia], and cheilosis) in
severe iron deficiency
Dysphagia resulting from esophageal webs (Plummer-
Vinson syndrome) may occur in severe iron deficiency
Pica (ie, craving for specific foods [eg, ice chips, lettuce]
often not rich in iron) is frequent
Source: Chapter 103. Iron Deficiency and Other Hypoproliferative Anemias
21. Investigations
Useful tests include the following:
Complete blood count
Peripheral blood smear
Serum iron, total iron-binding capacity (TIBC), and serum ferritin
Evaluation for hemosiderinuria, hemoglobinuria, and pulmonary hemosiderosis
Hemoglobin electrophoresis and measurement of hemoglobin A2 and fetal
hemoglobin
Reticulocyte hemoglobin content
Source: http://emedicine.medscape.com/article/202333-overview
22. Investigations
Tests useful for establishing the etiology of iron deficiency anemia and excluding
or establishing a diagnosis of another microcytic anemia include the following:
Stool testing
Incubated osmotic fragility testing
Measurement of lead in tissue
Bone marrow aspiration
Source: http://emedicine.medscape.com/article/202333-overview
23. Investigations
CBC results in iron deficiency anemia include the following:
Low mean corpuscular volume (MCV)
Low mean corpuscular hemoglobin concentration (MCHC)
Elevated platelet count (>450,000/µL) in many cases
Normal or elevated white blood cell count
Source: http://emedicine.medscape.com/article/202333-overview
24. Investigations
Peripheral smear results in iron deficiency anemia are as follows:
RBCs are microcytic and hypochromic in chronic cases
Platelets usually are increased
In contrast to thalassemia, target cells are usually not present, and
anisocytosis and poikilocytosis are not marked
In contrast to hemoglobin C disorders, intraerythrocytic crystals are not seen
Source: http://emedicine.medscape.com/article/202333-overview
25. Investigations
Results of iron studies are as follows:
Low serum iron and ferritin levels with an elevated TIBC are diagnostic of iron
deficiency
A normal serum ferritin can be seen in patients who are deficient in iron and
have coexistent diseases (eg, hepatitis or anemia of chronic disorders)
Source: http://emedicine.medscape.com/article/202333-overview
27. Management
Symptomatic elderly patients with severe iron-deficiency anemia and
cardiovascular instability may require red cell transfusions.
Younger individuals can be treated more conservatively with iron replacement.
For the majority of cases of iron deficiency (pregnant women, growing children
and adolescents, patients with infrequent episodes of bleeding, and those with
inadequate dietary intake of iron), oral iron therapy will suffice. For patients with
unusual blood loss or malabsorption, specific diagnostic tests and appropriate
therapy take priority. Once the diagnosis of iron-deficiency anemia and its cause is
made, There are three major therapeutic approaches.
1- RED CELL TRANSFUSION:
2- ORAL IRON THERAPY
3- PARENTERAL IRON THERAPY: saccharated ferric oxide (SFO) and cideferron (CF), for
those who are not tolerated with oral iron therapy.
Source: Harrison’s Principles of Internal Medicine 17th edition
29. Complications
Effects of Anemia in Pregnant Women
Pregnant women with significant anemia may have an increased risk for poor pregnancy outcomes,
particularly if they are anemic in the first trimester.
Complications from Anemia in Children and Adolescents
In children, severe anemia can impair growth and motor and mental development. Children may
exhibit a shortened attention span and decreased alertness. Children with severe iron-deficiency
anemia may also have an increased risk for stroke.
Effects of Anemia in the Elderly
Anemia is common in older people and can have significantly more severe complications than
anemia in younger adults. Effects of anemia in the elderly include decreased strength and increased
risk for falls. Anemia may have adverse effects on the heart and increase the severity of cardiac
conditions, including reducing survival rates from heart failure and heart attacks. Even mild anemia
may possibly lead to cognitive impairment or worsen existing dementia.
Iron Overload
Source: http://www.umm.edu/patiented/articles/what_symptoms_of_anemia_000057_4.htm#ixzz2P9eHzfYJ
31. Prevention
Good food sources of iron include the following:
Meats--beef, pork, lamb, liver, and other organ meats
Poultry--chicken, duck, turkey, liver (especially dark meat)
Fish--shellfish, including clams, mussels, oysters, sardines, and anchovies
Leafy greens of the cabbage family, such as broccoli, kale, turnip greens, and
collards
Legumes, such as lima beans and green peas; dry beans and peas, such as
pinto beans, black-eyed peas, and canned baked beans
Yeast-leavened whole-wheat bread and rolls
Iron-enriched white bread, pasta, rice, and cereals
Source: https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=90&ContentID=P02428
32. Prevention
Vitamin supplements containing at least 400 micrograms of folic acid are now
recommended for all women of childbearing age and during pregnancy. Food
sources of folate include the following:
Leafy, dark green vegetables
Dried beans and peas
Citrus fruits and juices and most berries
Fortified breakfast cereals
Enriched grain products
Source: https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=90&ContentID=P02428
34. Differential Diagnosis
Microcytic anemia resulting from other causes
Thalassemia
Anemia of chronic disease
Sideroblastic anemia
Lead poisoning
Source: Quick Medical Diagnosis & Treatment Book