This document discusses iron deficiency anemia (IDA), including: 1. Iron is an important bioactive element involved in oxygen transport, oxidative metabolism, and cellular growth. The majority of iron is found in hemoglobin and myoglobin, with smaller amounts in various enzymes. 2. Iron is absorbed in the small intestine and transported by transferrin in plasma. It is stored in ferritin and hemosiderin. Iron requirements vary between men and women. 3. IDA is common and caused by low dietary iron intake, increased demands, blood loss, or malabsorption. Common causes of blood loss include gastrointestinal issues, menstruation, and pulmonary or urinary problems. 4.

1. RBC Disorders - 2
Dr.CSBR.Prasad, M.D.,

2. Iron Deficiency Anemia

3. Importance of iron
Iron is quantitatively the most important
bioactive element in human enzymology with
roles in:
– Oxygen transport and storage
– Oxidative metabolism
– Cellular growth and proliferation

4. Haem - Proteins
• Hemoglobin 70%
• Myoglobin 5%
• Tissue specific haem proteins
– Cytochromes Eg: P450
– Oxygenases
– Hydroxylases
– Peroxidase
– Catalase
– Ribonucleotide reductase
– Aconitase

5. Proteins of iron
TRANSPORT & STORAGE
• TRANSFERRIN: Single chain glycoprotein with two
iron binding sites, responsible for iron transport
in plasma and extra-cellular fluid
• TRANSFERRIN RECEPTOR: Transmembrane
glycoprotein with two transferrin binding sites
• FERRITIN: Spherical protein of 24 subunits which
binds 4500 atoms of iron
• IRP: four domine cluster protein which co-
ordinates translocational regualtion of iron
proteins

6. Iron Distribution in Healthy
Young Adults (mg)
Pool Men Women
Total 3450 2450
Functional
Hemoglobin 2100 1750
Myoglobin 300 250
Enzymes 50 50
Storage
Ferritin, hemosiderin 1000 400

7. Iron metabolism

8. Iron balance
Absorption Excretion
• 7mg/1000kcal • Exfoliated epithelial cells of
• 20-30% of haem iron is the GI tract
absorbed • Exfoliated cells of the skin
• <5% of non haem iron is • Bile
absorbed
• Absorption is increased by • Urine
aminoacids & ascorbic acid • Menstrual blood loss
• Absorption is decreased by
phytates, phosphates and NO MECHANISM
tannates
FOR INCREASING
IRON EXCRETION

9. Free iron is highly toxic
Hence, storage iron is sequestered
– Ferritin or
– Hemosiderin

10. Ferritin & Hemosiderin
• Ferritin is a ubiquitous protein-iron complex
• Highest levels :
– liver, spleen, bone marrow, and skeletal muscles
• In the liver, most ferritin is stored within the
parenchymal cells
• Partially degraded protein shells of ferritin
aggregate into hemosiderin granules
• Since plasma ferritin is derived largely from the
storage pool of body iron, its levels correlate well
with body iron stores

11. Iron requirements
MEN WOMEN
• Daily basal iron loss • Menstruating: 1.5mg/day
<1mg/day • Pregnancy: 2mg/day or
• 10mg of iron in the diet 500mg for 280days of
with 10% absorption is gestation
sufficient to maintain iron
balance

12. Regulation of iron absorption

13. Iron absorption is regulated by
HEPCIDIN
• Nature: Small peptide
• Source: Liver
• Stimulus: Intrahepatic iron level dictates
Hepcidin synthesis
• Action:
– Inhibits ferroportin
– Hence, inhibits iron transfer from the enterocyte
to plasma

14. Diseases with abnormal iron metabolism
Basis: Alterations in hepcidin
• Anemia of chronic disease
• Mutations that disable TMPRSS6
• Primary and secondary hemochromatosis
– Associated with mutations in hepcidin or the
genes that regulate hepcidin expression
• Ineffective erythropoiesis suppresses hepatic
hepcidin production, even when iron stores
are high (unknown mechanim)

15. Prevalence of iron deficiency in India
• Pregnant women 70-90%
• Pre-school children 50%

16. Causes of iron deficiency
• Nutrional
– Decreased dietary intake
– Increased physiological demand
• Pregnancy
• Lactation
• Iron malabsorption Chase the
• Blood loss cause

17. Causes of blood loss
• Gastrointestinal
• Pulmonary
– Hemosiderosis
• Urinary
– Hematuria
– Hemoglobinuria
• Uterine
– Menorrhagia

18. Causes of GI blood loss
• Esophagus • Small intestine
– web – Meckel’s divrticulum
– Varices – Duodenal ulcer
– Reflux – Crohn’s
– Carcinoma • Large intestine
• Stomach – Polyps
– Ulcer – AV malformations
– Carcinoma – Carcinoma
– Leiomyoma – Ulcerative colitis
– Gastritis – Amebiasis
– Tuberculosis
– Hemorrhoids

19. Iron deficiency in children
• Most common between 1.5 to 4yrs
• Iron deficiency in children is so important
because of the possibility that there may be
irreversible impairment of cognitive skills

20. Blood and BM findings in IDA
Peripheral blood Bone marrow
• <HGB • Erythroid hyperplasia
• <MCV • Micronormoblastic
• <MCH maturation
• Microcytic hypochromic • Leucocytes and MKc may be
• Aniospoikilocytosis normal
• Pencil shaped cells
• Tailed poikilocytes
• There may be
Thrombocytosis

21. Microcytic hypochromic anemia of iron
deficiency (peripheral blood smear)

22. Why anisocytosis in iron deficiency?
It’s due to differences in availability of iron in
different areas of the bone marrow

23. Diagnosis of IDA

24. Laboratory evaluation of iron status
• Serum iron and iron binding capacity
• Serum ferritin
• Bone marrow iron status (Perl’s stain)
• Serum transferrin
• Plasma transferrin receptor
• RBC protoporphyrin

25. Serum transferrin receptor levels
• Good correlation with erythron mass
– Increased in hemolytic anemia
• Good correlation with iron deficiency in which
it’s increased
• Not increased in anemia of chronic disease

26. Important points

27. Regulation of fe balance is mainly by
absorption

28. Ferritn levels < 12 is indicative of fe
deficiency

29. “Chase the cause in bleeding”

30. Weakness in IDA is disproportionate to
HGB levels

31. Iron loss is mainly thru…..
• Hair growth
• Skin desquamation
• Menstruation / blood loss

32. Role of acid in fe absorption

33. Common cause of anemia in children

34. How gastrectomy causes anemia?
• Low or no acid secretion

35. How GJ causes anemia (IDA)

36. Causes for chronic blood loss

37. External bleeding Vs bleeding in to the
tissues and Fe deficiency

38. Occult colonic carcinoma -
• Ask for occult blood test on stool

39. Main causes for microcytic
hypochromic anemia
• Iron deficiency anemia
• Thalassemia
• Sideroblastic anemia
• Anemia of chronic disease

40. Sequence of events in iron deficiency
At presentation With treatment
• Disappearance of iron • Disappearance of
stores microcytosis
• Drop in hgb • Raise in hgb
• Microcytosis • Restoration of body iron
pool

41. END

42. Dr.CSBR.Prasad, M.D.,
Associate Professor of Pathology,
Sri Devaraj Urs Medical College,
Kolar-563101,
Karnataka,
INDIA.
csbrprasad@reiffmail.com