Anemia Introduction

Anemia Introduction

Dr. Sachin Kale, MD.Asso. Prof, Dept. of pathology

In charge, Central Laboratory, MGM.

Outline• Introduction to hematology and

hematopoiesis

• Introduction to anemias• Iron deficiency anemias• Megaloblastic anemia.• Sickle cell anemia

Anemias• Signifies a decrease in Hb or Hct and

represents underlying disease than a specific diagnosis

• Accepted definitions -• Male: < 13.5 g/dl• Female: < 12.5 g/dl• Pregnancy & Children - ( 6 m – 8 yrs): <

11 g/dl• Preterm infants: < 14 ; Full term infant: <

13.5

Anemias

• SaO2 ( % of heme groups occupied by O2) and PaO2 ( amount of O2 dissolved in plasma) are normal; since O2 exchange in lungs are normal.

• However oxygen content (total amt of O2 available) is decreased owing to reduction in Hb concentraion.

Mature RBC

• Anucleate cells• Devoid of mitochrondria – lack citric acid

cycle, beta oxidation of fatty acid, oxidative phosphorylation

• Metabolize glucose by anerobic glycosylation – lactate is the end product.

• Generate glutathione via pentose phosphate shunt.

Mature RBC

• Reduce heme iron from ferric (+3) to ferrous (+2) state using methemoglobin reductase system Synthesizes 2,3 bisphosphoglycerate via Rappapor-Luebering shunt. ( used for right shifts in O-D curve)

• ABO & Rh antigens on membranes.

Mature RBC

• Senescent RBCs are removed mainly by extravascular hemolysis – endproduct is lipid soluble unconjugated bilirubin.

• Lesser extent – intravascular hemolysis.

Basic pathophysiological categories of anaemia

• Blood loss

• Impaired red cell production• Inadequate supply of nutrients essential for

eythropoiesis, such as: .– iron deficiency– vitamin B 12 deficiency– folic acid deficiency– protein-calorie malnutrition– other less common deficiencies

Impaired red cell production

• Depression of erythropoietic activity• Anaemia associated with chronic disorders. such as:

– infection– connective tissue disorders– inflammatory disorders– disseminated malignancy– Anaemia associated with renal failure

• Aplastic anaemia• Anaemia due to inherited disorders, such as

thalassaemia

Impaired red cell production

• Anaemia due to replacement of normal bone marrow by:– Leukaemia– Lymphoma– myeloproliferative disorders– Myeloma– myelodysplastic disorders

Excessive red cell destruction

• Due to intrinsic defects in red cells• Due to extrinsic effects on red cells

General evidence of hemolysis

• Evidence of increased HB breakdown:– Jaundice and Hyperbilirubinemia

• Evidence of compensatory erythroid hyperplasia:– Reticulocytosis

• Evidence of damage to red cells:– Spherocytosis– Fragmentation RBCs– Heinz bodies

Classification of anemias

• Microcytic anemias: ( MCV < 80 fl)

• Iron deficiency (most common)• Thalassemia• Anemia of chronic disease• Sideroblastic anemia

Classification of anemias

• Macrocytic anemia (MCV > 100 fl)

• B12 deficiency• Folate deficiency• Alcoholic liver disease• Hypothyroidism

Normocytic anemia ( MCV 80 – 100 fl)

• Reti count: (< 2%)• Acute blood loss• Early iron deficiency• Aplastic anemia• Anemia of chronic disease• Renal disease

Normocytic anemia ( MCV 80 – 100 fl)

• Reti count: (> 3%) ( Intrinsic RBC defect)• Membrane defects

– Congenital spherocytosis/elliptocytosis– Paroxysmal Nocturnal Hemoglobinuria (PNH)

• Abnormal hemoglobins:– Sickle cell disease variants

• Enzyme deficiencies– G6PD & Pyruvate kinase deficiency.

Normocytic anemia ( MCV 80 – 100 fl)

• Reti count: (> 3%) ( Extrinsic RBC defect)• Autoimmune hemolytic anemias ( warm and

cold)• Paroxysmal cold hemoglobinuria• Microangiopathic hemolytic anemia

Work up of anemic patient

Chipmunk facies

RBCs in health and disease

Understanding CBC: the complete blood count

• Haematocrit is 3 times the HB value: Rule of 3.• RBC count usually parallels HB and Hct, • In thallasemias RBC count is normal to

increased even though Hb is low.• RDW: Red cell distribution width• WBC count: Total and differential• Blood film:

RBC indices

• MCV: volume of average red cell (fl or um3)MCV = Hctx1000/RBC count ( in millions per ul)

• MCH: content (wt) of Hb of average red cellMCH = Hb (g/l)/RBC ( in millions per ul)

• MCHC: average concentration of Hb in given volume of packed cells.MCHC: Hb(g/dl)/Hct

X’s Edition

Question 1

Iron deficiency anemia

Thalasemia

Alcoholic liver disease

Anemia of chronic disease

All of the following cause microcytic anemia except

Iron deficiency anemia

Thalasemia

Alcoholic liver disease

Anemia of chronic disease

All of the following cause microcytic anemia except

Question 2

Aplastic anemia

Hereditary spherocytosis

Acute blood loss

Anemia of renal disease

All of the following cause normocytic anemia with reti

count < 2%, except

Aplastic anemia

Hereditary spherocytosis

Acute blood loss

Anemia of renal disease

All of the following cause normocytic anemia with reti

count < 2%, except

Question 3

MCV = Hctx1000/RBC count

MCH = Hb (g/l)/RBC

MCHC: Hb(g/dl)/Hct

All of the above

Which of the following is True

MCV = Hctx1000/RBC count

MCH = Hb (g/l)/RBC

MCHC: Hb(g/dl)/Hct

All of the above

Which of the following is True

Question 4

26 yr, female, routine Check up. CBC = Low

MCV, Low Hb, WBCs: N

Positive Sickle screen

Increased HbA2 & F

Normocytic ane. Increased reti

Low Sr. Ferritin

You expect further studies to reveal

Positive Sickle screen

Increased HbA2 & F

Normocytic ane. Increased reti

Low Sr. Ferritin

You expect further studies to reveal

Question 5

Low Ferritin concentration

Microcytic RBC Indices

Abnormal Hb electrophoresis

All of the above

Which of the following is present in both IDA & Thalassemia

Low Ferritin concentration

Microcytic RBC Indices

Abnormal Hb electrophoresis

All of the above

Which of the following is present in both IDA & Thalassemia

• A well executed CBC followed by its proper interpretation has its worth in gold and a shrewd clinician make use of this simple and cheap test for diagnosing hematological and even non-hematological disorders..

Dr. M. B Agrawal.

Thank you!