This document provides an overview of anemia, including its classification, causes, clinical features, laboratory diagnosis, and pathophysiology. Anemia is defined as a hemoglobin level below the normal range based on age and sex. It can be classified based on red blood cell size (microcytic, normocytic, macrocytic) or pathophysiology (blood loss, impaired RBC production, increased RBC destruction). Common causes include iron deficiency, B12/folate deficiency, blood loss, hemolytic disorders, and bone marrow disorders. Clinical features depend on the severity and speed of onset of anemia. Laboratory evaluation includes complete blood count, RBC indices, peripheral smear, and additional

1. ANEMIA- Classification, C/F,
laboratory diagnosis
Dr. Sunita B. Patil
Department of Pathology
DYPMCK

2. Divide along diff
cell lineages

3. RBCs -
• Biconcave disc 7.2µ
• membrane – spectrin – flexibility
• No nucleus
• no centrioles – no cell division
• no mitochondria – energy obtained anerobically
90% protein in RBC is Hb – affinity to O₂

4. ANEMIA
• Anaemia is defined as a haemoglobin
concentration in blood below the lower
limit of the normal range for the age and sex
of the individual.

5. Anemia
A reduction in Hb Con & RBC count bellow the normal
level
Lower limit of Hb for M – 13.0 gm%
F - 11.5 gm%
child– 9.5 gm%
new born – 15 gm%
Hematocrit (<40% in M,<36% in F)

6. • haemoglobin value is the major parameter
for determining anaemia,
• the red cell counts, haematocrit (PCV) and
absolute values (MCV, MCH and MCHC)
provide alternate means of assessing
anaemia.

7. Body will try to compensate ANAEMIA by
Red cell mass - Erythropoietin – KIDNEY
erythroid hyperplasia
reticulocytes , normoblasts on PS
Expansion of marrow cavity
bone pain even bone deformity
Blood flow- cardiac output- heart rate & pulse
viscosity of blood - murmurs
By decreasing Hb affinity to O2 – BY 2-3 DPG

8. 2 -3 diphosphoglycerate(DPG)
- metabolite in EMP
it forms bond between two beta chains by
replacing O2 2-3DPG - 02 affinity of Hb
(Tense Hb or deoxyHb)
more O2 is released at tissue level
2-3 DPG - 02 affinity of Hb (Relax Hb oxy Hb )

10. Pathophysiology of Anaemia
• Subnormal level of haemoglobin causes
lowered oxygen carrying capacity of the blood.
• This, in turn, initiates compensatory
physiologic adaptations such as follows:
increased release of oxygen from
haemoglobin;
increased blood flow to the tissues;
maintenance of the blood volume; and
redistribution of blood flow to maintain the
cerebral blood supply

11. Hb concentration
02 carrying capacity of blood
-Tissue hypoxia , anoxia – Normal functioning is affected
-The degree of functional impairment of individual
tissues is variable depending upon their oxygen
requirements.
-Tissues with high oxygen requirement such as the
heart, CNS and the skeletal muscle during exercise,
bear the brunt of clinical effects of anaemia.
S/S of anemia are according to the system involved

12. Clinical Features of Anaemia
• The haemoglobin level at which symptoms and
signs of anaemia develop depends upon 4 main
factors:
1. The speed of onset of anaemia:
Rapidly progressive anaemia causes more
symptoms than anaemia of slow-onset as there is
less time for physiologic adaptation.

13. 2. The severity of anaemia:
Mild anaemia produces no symptoms or signs
but a rapidly developing severe anaemia
(haemoglobin below 6.0 g/dl) may produce
significant clinical features.

14. 3. The age of the patient:
• The young patients due to good cardiovascular
compensation tolerate anaemia quite well as
compared to the elderly.
• The elderly patients develop cardiac and
cerebral symptoms more prominently due to
associated cardiovascular disease.

15. 4. The haemoglobin dissociation curve:
In anaemia, the affinity of haemoglobin for oxygen is
depressed as 2,3-BPG in the red cells increases. As a
result, oxyhaemoglobin is dissociated more readily
release free oxygen for cellular use, causing a shift of
the oxyhaemoglobin dissociation curve to the right.

16. A
N – Sigmoid curve
Hypoxia – shift to R
shift to L –
Abnormal Hb
Hb F
MethaeHb/carboxy

17. SYMPTOMS.
• In symptomatic cases of anaemia, the presenting
features are:
• tiredness, easy fatiguability, generalised muscular
weakness, lethargy and headache.
• In older patients, there may be symptoms of
cardiac failure, angina pectoris, intermittent
claudication, confusion and visual disturbances.

18. SIGNS
1. Pallor.
Pallor is the most common and characteristic sign,
seen in the mucous membranes, conjunctivae and skin.
2. Cardiovascular system.
A hyperdynamic circulation may be present with tachycardia,
collapsing pulse, cardiomegaly, midsystolic flow murmur,
dyspnoea on exertion, and in the case of elderly, congestive
heart failure.
3. Central nervous system.
The older patients may develop attacks of faintness,
giddiness, headache, tinnitus, drowsiness, numbness and
tingling sensations of the hands and feet.

19. 4. Ocular manifestations.
Retinal haemorrhages may occur if there is associated
vascular disease or diathesis.
5. Reproductive system.
Menstrual disturbances such as amenorrhoea and
menorrhagia and loss of libido
6. Renal system.
Mild proteinuria and impaired concentrating
capacity of the kidney may occur in severe anaemia.
7. Gastrointestinal system.
Anorexia, flatulence, nausea, constipation and weight
loss may occur.

21. How to investigate a case of Anemia
1) Detail Medical History
2 ) Physical examination
3) Laboratory Investigations

22. Detail medical History – to find underlying cause
•Onset - Acute or Insidious
• Family History – Hemorrhagic & coagulation
disorders, Hemoglobinopathies, Recurrent jaundice
•Occupation – Exposed to chemicals solvent , drugs
•Native place - geographical distribution
schistosomiasis, kala azar

23. Dietary history
Shoud be specific, meal by meal
Vegeterian /nonveg
Economical status – malnutrition
regarding dietary fads, cooking habits (folic acid & vit c
destroys with excess cooking )
Recent loss weight / poor dentures

24. • fever – infections, lymphoma, collagen
vascular diseases
• cough/ hemoptysis – lung neoplasms,
infections
• Pain in limbs, paraesthesia – Pernicious anemia
• H/O abdominal pain – ulcers, gastritis
•H/O passing worms in stool

25. Changes in bowel habbit– colonic neoplasms
Suspect upper GI bleed – if H/o Malena, Hematemesis
lower GI bleed - fresh rectal bleeding
Aspirin, NSAIDs, steroids – Peptic ulcer
Alcohol abuse – cirrhosis – oesophageal varices
•H/O recent surgery with blood loss.
• Any complications during the operation

26. H/O taking antibiotics - can reduce platelets
M/H – Menorrhagia - bleeding > 7day
no of pads used/cycle >12
passage of clots after 1st day
Obs/H – No of pregnancies, No of Abortions

27. physical examination
• pallor on mucous membrane, conjunctiva, yellow
( Icterus ) – Hemolytic Anemia
• nails – brittleness & concave in IDA
• Tongue- thick, red, beefy - Megaloblastic anemia
Burning sensation with atropic glossitis - IDA
HS megaly, LN pathy , bony tenderness – Leukemias
Suspect bleeding disorders when patechiae, bruises,
ecchymosis
Early greying of hair , angular stomatitis - IDA

28. physical examination -
pallor on conjunctival rim – most common

29. Nail – koilonychia Tongue – atropic glossitis

30. LAB Investigations –
complete blood counts (CBC) with reticulocyte count is
the basic test.
CBC
Hb
RBC count,
PCV (HCT)
RBC Indices (MCV, MCH, MCHC)
RDW
Platelet count

31. Hb - Men : 15.5±2.5 gm/dl
women : 14±2.5 gm/dl
RBC count –: men – 5.5±1 × 1012 /l
: women – 4.8± 1× 1012 /l
PCV (HCT) – Volume of erythrocytes/l of blood
N : 40-54 %.
From these values series of Indices derived
MCV – PCV/RBC – 77-93 femtolitre
MCH – HB/RBC – 27-32 pg
MCHC – HB/PCV – 30 -35gm%
RDW - 12 -15 %

32. A. HAEMOGLOBIN ESTIMATION
• most reliable and accurate is the
cyanmethaemoglobin (HiCN) method
employing Drabkin’s solution and a
spectrophotometer.
• If the haemoglobin value is below the lower
limit of the normal range for particular age
and sex, the patient is said to be anaemic.
• In pregnancy, there is haemodilution and,
therefore, the lower limit in normal
pregnant women is less (10.5 g/dl) than in
the non-pregnant state.

33. B. PERIPHERALBLOOD FILM EXAMINATION
The Hb estimation is invariably followed by
examination of a peripheral blood film for
morphologic features after staining it with the
Romanowsky dyes (e.g. Leishman’s stain, May-
Grünwald-Giemsa’s stain, Jenner- Giemsa’s stain,
Wright’s stain etc).

34. The following abnormalities in red blood cells
are looked for in a blood smear:
1. Variation in size (Anisocytosis).
2. Variation in shape (Poikilocytosis).
3. Inadequate haemoglobin formation
(Hypochromasia).
4. Compensatory erythropoiesis.

35. 1. Variation in size (Anisocytosis).
• Microcytes
• Macrocytes
• Dimorphic

36. Microcytic hypochromic, Anisopoikilocytosis

38. Macrocytic RBCs – ovalocytes +

39. 2. Variation in shape (Poikilocytosis).

40. See for abnormal forms of RBCs-
spherocytes / elliptocytes /stomatocytes– AHA
Scistocytes – HA ( MAHA )
sickle cells – Sickle cell Anaemia
Target cells – Thalasemia
Bur cells (Echinocytes – crenated RBC )
- uraemia .
Acanthocytes – Liver Diseases

41. Spherocytes – RBCs small, with no central pallor, & reticulocyte
hereditary spherocytosis, autoimmune haemolytic
anaemia and in ABO haemolytic disease of the newborn.

42. Elliptocytosis

43. stomatocytes
hereditary stomatocytosis, chronic alcoholism.

44. Target cells

45. Tear drop cells (Dacrocyte)

46. Schistocytes – irregular helmet shaped - MAHA
thalassaemia, hereditary elliptocytosis, megaloblastic anaemia, IDA,
microangiopathic haemolytic anaemia and in severe burns.

48. Sickle cells

49. Echinocytes – Crenated RBCs

50. Acanthocytes ( spur cells ) – severe liver D
splenectomised subjects, chronic liver disease.

52. 3. Inadequate haemoglobin formation
(Hypochromasia).
• Increased central pallor is referred to as
hypochromasia.
• It may develop either from lowered haemoglobin
content (e.g. in iron deficiency anaemia, chronic
infections), or due to thinness of the red cells (e.g. in
thalassaemia, sideroblastic anaemia).
• Unusually deep pink staining of the red cells due to
increased haemoglobin concentration is termed
hyperchromasia and may be found in megaloblastic
anaemia, spherocytosis and in neonatal blood.

54. 4. Compensatory erythropoiesis
i) Polychromasia
• is defined as the red cells having more than one type
of colour.
• Polychromatic red cells are slightly larger, generally
stained bluish-grey and represent reticulocytes
• thus, correlate well with reticulocyte count.
ii) Erythroblastaemia
• is the presence of nucleated red cells in the PBS.
• haemolytic disease of the newborn, other
haemolytic disorders and in extramedullary
erythropoiesis, severe anaemias except in aplastic
anaemia, splenectomy.

55. Polychromatic RBCs – Compensatory HA

56. Normoblasts

57. iii) Punctate basophilia or basophilic stippling
• is diffuse and uniform basophilic granularity in
the cell which does not stain positively with
Perls’ reaction
• Classical punctate basophilia is seen in aplastic
anaemia, thalassaemia, myelodysplasia,
infections and lead poisoning.
iv) Howell-Jolly bodies
• are purple nuclear remnants, usually found
singly, and are larger than basophilic stippling.
• They are present in megaloblastic anaemia and
after splenectomy.

58. RED CELL INDICES
• An alternative method to diagnose and detect the
severity of anaemia is by measuring the red cell
indices:
• In iron deficiency and thalassaemia, MCV, MCH and
MCHC are reduced.
• In anaemia due to acute blood loss and haemolytic
anaemias, MCV, MCH and MCHC are all within
normal limits.
• In megaloblastic anaemias, MCV is raised above the
normal range.

59. LEUCOCYTE AND PLATELET COUNT
• Measurement of leucocyte and platelet count
helps to distinguish pure anaemia from
pancytopenia in which red cells, granulocytes
and platelets are all reduced.
• In anaemias due to haemolysis or
haemorrhage, the neutrophil count and
platelet counts are often elevated.
• In infections and leukaemias, the leucocyte
counts are high and immature leucocytes
appear in the blood.

60. • RETICULOCYTE COUNT.
• Reticulocyte count (normal 0.5-2.5%) is done in each case
of anaemia to assess the marrow
• Haematology and Lymphoreticular Tissues erythropoietic
activity.
• In acute haemorrhage and in haemolysis, the reticulocyte
response is indicative of impaired marrow function.
• ERYTHROCYTE SEDIMENTATION RATE.
• The ESR is a non-specific test used as a screening test for
anaemia.
• It usually gives a clue to the underlying organic disease but
anaemia itself may also cause rise in the ESR.
• BONE MARROW EXAMINATION.
• Bone marrow aspiration is done in cases where the cause
for anaemia is not obvious.

61. Other investigations
Urine examination
Biochemistry Investigations - RFT /LFT
Stool Examination
Ultrasonography
Barium meal study
Cystoscopy / Endoscopy

62. Microcytic hypochromic (MCV<81)
iron deficiency, thalassemia, sideroblastic anemia, anemia of
chronic disease, lead poisoning
Normocytic normochromic (MCV 81-98)
anemia of chronic disease, aplastic anemia, acute blood loss.
bone marrow infiltration, kidney disease, liver diseases
Macrocytic normochromic(MCV >98):
alcohol, B12 deficiency, folate deficiency, myelodysplasia
Morphological classification of anaemia

63. Complete blood count with RBC Indices
MCV < 80 MCV 80 -100 MCV > 100
Microcytic A Normocytic A Macrocytic A
IDA Haemorrhage Megaloblastic
Thalassemia Hemolytic A Non megaloblastic
Sideroblastic A Aplastic A Alcohol abuse
Chronic diseases Leukemia Liver diseases, MDS
Lead poisoning
S Iron TIBC Retic count Macrocytes ++
Tra sat IDA RDW HA, Haemorrhage Hyperseg N ++
Ferritin aplastic A Leukemia Vit B12
Folic A assay
TIBC , CD Ferritin
Thalassemia
RDW - N
Hb A2 Hb F
Sid A -TSL, Ferritin
Iron stain
Lead pois -

64. Pathophysiological classification of Anaemia
A) Anaemia due to blood loss
B) Anaemia due to impaired RBC production
C) Anaemia due to increased RBC destruction

65. I. Anaemia due to blood loss.
A. Acute post-haemorrhagic anaemia
B. Anaemia of chronic blood loss

66. II. Anaemias due to impaired red cell production
a) Cytoplasmic maturation defects
1. Deficient haem synthesis: Iron deficiency anaemia
2. Deficient globin synthesis: Thalassaemic syndromes
b) Nuclear maturation defects
Vitamin B12 and/or folic acid deficiency:
Megaloblastic anaemia
c) Defect in stem cell proliferation and differentiation
1. Aplastic anaemia
2. Pure red cell aplasia
d) Anaemia of chronic disorders
e) Bone marrow infiltration
f) Congenital anaemia

67. A. Cytoplasmic maturation defects
B. Nuclear maturation defects
Vitamin B12 and/or folic acid deficiency:
C. Haematopoietic stem cell proliferation and differentiation
abnormality e.g. 1. Aplastic anaemia 2. Pure red cell aplasia
D. Bone marrow failure due to systemic diseases (anaemia of chronic
disorders) e.g.
1. Anaemia of inflammation/infections, disseminated malignancy
2. Anaemia in renal disease
3. Anaemia due to endocrine and nutritional deficiencies
(hypometabolic states)
4. Anaemia in liver disease
E. Bone marrow infiltration e.g.
1. Leukaemias 2. Lymphomas 3. Myelosclerosis 4. Multiple myeloma
F. Congenital anaemia e.g.
1. Sideroblastic anaemia 2. Congenital dyserythropoietic anaemia.

68. III. Anaemias due to increased red cell destruction
(Haemolytic anaemias)
A. Extrinsic (extracorpuscular) red cell abnormalities
B. Intrinsic (intracorpuscular) red cell abnormalities

71. Thank
you