Anemia is caused by a decrease in hemoglobin levels or red blood cell count. There are several types of anemia classified by etiology or morphology. Iron deficiency anemia, the most common type worldwide, is caused by inadequate iron intake or increased iron loss. Megaloblastic anemias like pernicious anemia result from vitamin B12 or folate deficiencies and are characterized by abnormally large red blood cells. Pernicious anemia specifically involves failure of intrinsic factor secretion due to gastric atrophy. Treatment involves vitamin B12 injections to correct the deficiency.

1. ANAEMIA
DR RASHMI MISHRA

2. RBC DISORDERS (ANEMIAS)
• “Anemia is decreased red cell mass affecting
tissue oxygenation”
Practical - Low Hb* or Low Hematocrit*

3. ANEMIA
• Anemia means a decrease in hemoglobin
content, or RBCs count, or both of them below
the normal range.
• Anemia leads to a decrease in blood ability to
transport oxygen to tissue cells.

4. LOW RBC COUNT(<4MILLION/CMM)
• Anaemia is labelled
when Hb Conc is
- less 13 gm/dl in adult
males
-11.5 gm/dl in adult
females
- 15 gm/dl in newborns
-9.5 gm/dl at 3 month of
age
• Gradings of Aneamia
-Mild Aneamia
Hb 8-10 Gm%
-Moderate Aneamia
6-8 Gm%
-Severe Aneamia
Hb <6 Gm%

5. CLASSIFICATION

6. AETIOLOGICAL (WHITBY’S)
CLASSIFICATION
• Types of anaemia depending upon the causative
mechanism are:
A. Deficiency anaemias
- Iron deficiency anaemia
- Megaloblastic anaemia (pernicious anaemia) due to
deficiency of vitamin B12
- Megaloblastic anaemia due to deficiency of folic acid
Protein and vitamin C deficiency can also cause anaemia.

7. CONTD.....
• B. Blood loss anaemias or haemorrhagic
anaemias are commonly known and can be:
-Acute post-haemorrhagic anaemia as in
accidents
-Chronic post-haemorrhagic anaemia

8. • Haemolytic anaemias. These are relatively
uncommon and occur in conditions associated with
increased destruction of RBCs. These can be:
1. Hereditary haemolytic anaemias,
e.g. as seen in: Thalassaemia
Sickle cell anaemia
Hereditary spherocytosis
Glucose 6-phosphate dehydrogenase (G6PD)
deficiency.

9. • 2. Acquired haemolytic anaemias such as
Immunohaemolytic anaemia (due to
antibodies against RBCs)
Haemolytic anaemia due to direct toxic effects
(e.g. in malaria, snake venom, toxic effects of
drugs and chemicals, etc.)
Haemolytic anaemia in splenomegaly
Haemolytic anaemia in paroxysmal nocturnal
haemoglobinuria

10. CONTD.....
• Aplastic anaemia. It occurs due to the failure
of bone marrow to produce RBCs.
• Anaemia due to chronic diseases. It is seen in
tuberculosis, chronic infections, malignancies,
chronic lung diseases, etc.

11. MORPHOLOGICAL (WINTROBE’S)
CLASSIFICATION
• Based on the mean cell volume (MCV), i.e. cell
size and the mean corpuscular haemoglobin
concentration (MCHC)
1. Normocytic normochromic anaemias. These are
characterized by normal MCV (78–94 μm3 or 78–
94 μL) and normal MCHC (30–38%). Such a
morphological picture is seen in:
- Acute post-haemorrhagic anaemia,
- Haemolytic anaemias and
- Aplastic anaemias.

12. CONTD.....
• Microcytic hypochromic anaemias. These are
characterized by reduced MCV (< 78 μm3) and
reduced MCHC (< 30%). Examples of such
anaemias are:
- Iron deficiency anaemia,
- Chronic post-haemorrhagic anaemia and
- Thalassaemia

13. CONTD......
• Macrocytic normochromic anaemia. It is
characterized by increased MCV (> 94 μm3)
and normal MCHC (30–38%). Examples are:
- Megaloblastic anaemia (pernicious anaemia)
due to deficiency of vitamin B12 and
- Megaloblastic anaemia due to deficiency of
folic acid.

14. GENERAL CLINICAL
FEATURES OF ANAEMIA

16. IRON DEFICIENCY ANAEMIA
• Iron deficiency anaemia is the commonest
nutritional deficiency disorder present
throughout the world, but its prevalence is higher
in the developing countries. In India, iron
deficiency is the commonest cause of anaemia.
Iron deficiency anaemia is much more common:
-In women between 20–45 years than in men,
- At periods of active growth in infancy, childhood
and adolescence.

17. • Daily requirement. Only 10% of the dietary intake of
iron is absorbed. Therefore, daily requirement in
the adult males is 5–10 mg/day and in females is 20
mg/day (to compensate the menstrual loss).
Pregnant and lactating women require about 40 mg
of iron per day.
• Dietary sources. Foodstuffs vary both in their iron
content and availability of iron for absorption into
the body. The dietary sources of iron are meat, liver,
egg, leafy vegetables, whole wheat and jaggery. The
iron in foods of animal origin is better absorbed
than iron in foods of vegetable origin

19. CAUSES OF IRON DEFICIENCY
ANAEMIA
1. Inadequate dietary intake of iron as in:
- Milk fed infants,
- Poor economic status individuals,
- Anorexia, e.g. in pregnancy and
- Elderly individuals due to atrophy and poor dentition.
2. Increased loss of iron (as blood loss) from the body,
e.g.
-Uterine bleeding in females in the form of excessive
menstruation, repeated miscarriages, postmenopausal
bleeding, etc

20. 3. Increased demand of iron as in:
- Infancy, childhood and adolescence,
- Menstruating females and
- Pregnant females.
4. Decreased absorption of iron, as seen in:
-Partial or total gastrectomy,
- Achlorhydria and
- Intestinal malabsorption diseases

21. Laboratory findings
• 1. Blood picture and red cell indices
- Hb concentration is decreased.
- RBCs are hypochromic (deficient in Hb)
and microcytic (smaller in size). They
show anisocytosis and poikilocytosis.
- Red cell indices like MCV, MCH and
MCHC are decreased.

22. • 2. Bone marrow findings
- Marrow cellularity: Erythroid hyperplasia,
- Erythropoiesis: normoblastic and
- Marrow iron: Deficient.
• 3. Biochemical findings
- Serum iron decreases, often under 50 mg%
(normal 60–160 mg%).
- Serum ferritin is very low indicating poor tissue
iron stores.
- Total iron binding capacity is increased

24. MEGALOBLASTIC ANAEMIA
• Megaloblastic anaemias are characterized by
the abnormally large cells of erythrocyte
series.
• These are caused by defective DNA synthesis
due to deficiency of vitamin B12 and/or folic
acid (folate)

25. AETIOLOGICAL TYPES
• I. Megaloblastic anaemia due to vitamin B12 deficiency
Causes of vitamin B12 deficiency are:
1. Inadequate dietary intake may occur in: Strict
vegetarians and Breast-fed infants.
2. Malabsorption of vitamin B12 is more often the cause
of deficiency and may be due to:
- Gastric causes leading to the deficiency of intrinsic
factors such as an autoimmune cause of failure of
secretion of intrinsic factor (Addisonian pernicious
anaemia), gastrectomy and congenital lack of intrinsic
factor.
- Intestinal causes which are associated with decreased
vitamin B12 absorption are tropical sprue, ileal
resection, Crohn’s disease, fish tapeworm infestation
and intestinal blind loop syndrome.

26. • Megaloblastic anaemia due to folate
deficiency
Causes of folate deficiency are:
1. Inadequate dietary intake due to poor intake
of vegetables as seen in poor people, infants
and alcoholics.
2. 2. Malabsorption, e.g. in coeliac disease,
tropical sprue and Crohn’s disease.

27. • 3. Increased demand as occurs in:
- Physiological conditions, such as pregnancy,
lactation and infancy and
- Pathological conditions of cell proliferation, such
as increased haematopoiesis (as in haemolysis)
and malignancies.
• 4. Effect of drugs, such as certain anticonvulsants
(e.g. phenytoin), contraceptive pills and certain
cytotoxic drugs (e.g. methotrexate).
• 5. Excess urinary folate loss, e.g. in active liver
disease and congestive heart failure.

31. ADDISONIAN PERNICIOUS ANAEMIA
• Aetiology.
- Addisonian pernicious anaemia is the term
which is used specifically for the megaloblastic
anaemia due to vitamin B12 deficiency
occurring as a result of failure of secretion of
intrinsic factor by the stomach owing to an
autoimmune atrophy of gastric mucosa.

32. - Thus, pernicious anaemia is an autoimmune
disease and in about 50% of patients,
antibodies to intrinsic factor can be
demonstrated.
- The disease is rare before the age of 30 years,
occurs mainly between 45 and 65 years, and
affects females more frequently than males

33. SYMPTOMS
• Anaemia
• Glossitis
• Neurofibromatosis
• Congestive heart failure
• GIT manifestations (anorexia ,diarrhoea,
weight loss)
• Haemorrhagic manifestations

34. CONTD....
• Features of pernicious anaemia include:
Specific features of pernicious anaemia are:
– Anti-intrinsic factor antibodies in serum (present
in 50% cases)
– Abnormal vitamin B12 absorption test corrected
by the addition of intrinsic factor (Schilling test).
• Treatment of pernicious anaemia consists of
regular administration of vitamin B12 by
intramuscular route: