Anemia can be caused by a decrease in red blood cell production due to iron deficiency or deficiencies in vitamins B12 or folic acid. Iron deficiency anemia is common in women of reproductive age due to menstrual blood loss. Vitamin B12 or folic acid deficiencies can cause megaloblastic anemia characterized by abnormally large red blood cells. Pernicious anemia is caused by vitamin B12 deficiency due to failure of intrinsic factor secretion in the stomach. Laboratory tests can identify microcytic anemia from iron deficiency or megaloblastic anemia from vitamin deficiencies.

1. Anemia
Physiology
Project
Kazan State Medical University
By:Mahi

2. ANAEMIA
Definition:
 Anemia is defined as a
decreased O2 carrying
capacity due to quantitative
and qualitative Reduction in
RBC counts and Hemoglobin
levels.
By:Mahi

3. ANAEMIA
 ANAEMIA is labelled
when Hb is less than
 13gm/dl in Males
 11 gm/dl in Females
 15gm/dl in Newborn.
By:Mahi

4. By:Mahi

5. MORPHOLOGICAL CLASSIFICATION:
normochromic
By:Mahi

6. Etiological Classification
By:Mahi

7. DUE TO DECREASED RBC
PRODUCTION.
IRON DEFICIENCY
ANAEMIA.
 In women of
reproductive age group
(20-45 yrs)
 In periods of active
growth of infancy,
childhood & adolescence
By:Mahi

8. IRON METABOLISM
 Total body contains 4-5
gms
 Forms –
 Haemoglobin 70%
 Storage iron 20-23% 2/3rd
Ferritin & 1/3rd
Haemosiderin.
 Myoglobin in red muscles
5%
 Intracellular enzymes 2-3%
By:Mahi

9. DAILY REQUIREMENTS &
SOURCES
 5-10 mg/day in Males
 20 mg/day in
Females.
 40 mg/day in
Pregnant & lactating
women.
 Meat, liver, egg, green
leafy veg, Jaggery &
whole wheat.
By:Mahi

10. By:Mahi

11. IRON
ABSORPTION
 Mainly in duodenum &
upper jejunum.
 MECHANISM
 Transport across brush
borders
 Haeme iron
 Non-haeme iron.
 Fate in Enterocytes.
 Transport in plasma.
By:Mahi

12. IRON ABSORPTION
 Transport across brush
borders.
 Absorption of Haeme
form
 Absorption of Non-
haeme form
 Fate in Enterocytes.
 Transport in plasma.
By:Mahi

13. Factors affecting iron
absorption
 Form of dietary iron –
 haem iron
 Non-haem iron – ferrous form (Fe2+) > ferric form
(Fe3+)
 Meat & fish ,Human breast milk ,Acid gastric
juice – enhances absorption.
 Dietary factors – Phytates , phosphates, calcium,
egg white, phenols, tea, coffe wine reduces.
 Iron stores in body – Negative feedback effect.
By:Mahi

14. STORAGE OF IRON
 As ferritin
 As haemosiderin.
By:Mahi

15. REGULATION OF BODY IRON
 Mucosal block theory of absorption.
 Saturation of apoferritin & apotransferrin
 Decresed rate of apoferritin synthesis.
 Role of specific iron receptors in brush borders.
By:Mahi

16. By:Mahi

17. By:Mahi

18. APPLIED ASPECTS.
 Iron deficiency- iron
deficiency Anaemia
 Iron excess –
Haemosiderin
accumulation –
Haemosiderosis –
damages tissue –
Haemochromatosis.
By:Mahi

19. CAUSES OF IRON DEFICIENCY
ANAEMIA.
 Inadequate dietary
intake.
 Increased loss of iron.
 Increased demand of
iron.
 Decreased absorption.
By:Mahi

20. Megaloblastic Anaemia
 Megaloblast –
abnormally large cells
of Erythroid series.
 Caused by defective
DNA synthesis due to
deficiency of Vit B12 &
Folic acid.
By:Mahi

21. Vit B 12 (Extrinsic Factor)
 Vit B12 –
Cyanocobalamin or
extrinsic factor.
 Daily need – 1-2 μg.
 Sources – Milk, Meat,
Liver of Animals
 Also synthesized by
bacterial Flora.
By:Mahi

22. Vit B 12 (Extrinsic Factor)
 Absorption – need
Intrinsic Factor Of Castle ,
a glycoprotein secreted by
parietal cells of gastric
mucosa.
 With it form Intrinsic
Factor- Cyanocobalamin
complex
 Bound to sp receptors in
ileum & absorbed by
Endocytosis.
By:Mahi

23. Vit B 12 (Extrinsic Factor)
 Transport – in blood
transported by
combining with
Transcobalamin-II
 Storage – In liver &
Muscle
 Role – required for
synthesis of DNA &
maturation of nucleus &
cell.
By:Mahi

24. Folic Acid
 Folic acid –
Pteroylglutamic acid.
 Daily requirement –
100 μg.
 Sources – leafy veg,
pulses, yeasts, liver.
 From breakdown of
Polyglutamate to
Monoglutamates.
By:Mahi

25. Aetiology.
 Due to vit B12
deficiency
 Causes –
 Inadequate dietary
intake
 Malabsorption due to
gastric cause
 Intestinal Cause.
By:Mahi

26. Addisonian Pernicious
Anaemia.
 Aetiology – vit B12
deficiency due to
failure of secretion of
Intrinsic Factor by
stomach due to
Autoimmune
Atrophy of Gastric
Mucosa.
 Features.
 Features of
Megaloblastic anaemia
 Anti-intrinsic factor
antibodies.
 Schilling test.
(abnormal vit B12
absorption test
corrected by addition
of Intrinsic Factor)
By:Mahi

27. Clinical Features:
 General features of Anemia
 Pallor, Weakness, Lethargy,
 Breathlessness on exertion
 Palpitations  heart failure  pedal edema
 Special features :
 Angular cheilitis, Atrophic glossitis,
 Oesophageal atrophy/web  Dysphagia,
 Koilonychia, brittle nails, gastric atrophy.
By:Mahi

28. Special features :
By:Mahi

29. LAB FINDINGS
 Blood picture & red cell
indices.
 Hb Decreased
 RBC – Microcytic,
Hypochromic in iron
deficiency
 Megaloblastic in vit B12 &
FOLIC ACID deficiency
 Red cell indices – MCV,MCH
& MCHC Decreases
By:Mahi

30. BONE MARROW FINDINGS.
 Iron deficiency
anaemia
 Marrow Cellularity –
Erythroid Hyperplasia.
 Erythropoiesis –
Normoblastic
 Marrow Iron –
Deficient.
 Megaloblastic
anaemia.
 Marrow cellularity –
Megaloblastic
Hyperplasia.
 Marrow iron – by
Prussian Blue staining
increase in size & no of
iron granules.
By:Mahi

31. THANK
YOU
By:Mahi