hematopoeisis

Bone marow examination Bone marow examination

Normal bone marrow Normal bone marrow

1. Haemopoietic cells. Morphology of haemopoietic cells 1. Haemopoietic cells. Morphology of haemopoietic cells Granulocytes & their precursors – 60%Granulocytes & their precursors – 60% Erythroid precursors – 20 %Erythroid precursors – 20 % Lymphocytes & Monocytes & their precursors – 10% Lymphocytes & Monocytes & their precursors – 10% Unidentified or disintegrating cells – 10%Unidentified or disintegrating cells – 10%

2. Myeloid : erythroid ratio – 3-4 :1 2. Myeloid : erythroid ratio – 3-4 :1

Anaemia Anaemia Anaemia may be defined as a state in which the blood Hg is Anaemia may be defined as a state in which the blood Hg is

below the normal range fro the age & sex of the patientbelow the normal range fro the age & sex of the patient

Normal count/Range Normal count/Range

Hemoglobin Hemoglobin Male – 13 –18 gm/dl Male – 13 –18 gm/dl Female -11.5 – 16.5 gm/dlFemale -11.5 – 16.5 gm/dl

Red cell count – Red cell count – Male - 4.5–6.5 million/cu mm of bloodMale - 4.5–6.5 million/cu mm of blood Female – 3.8–4.8Female – 3.8–4.8 Reticulocyte count - 0.2–2.0%Reticulocyte count - 0.2–2.0%

Hemoglobin (Hb)

g/dL 13.6-17.2 12.0-15.0

Red cell count

×106/mm3 4.3-5.9 3.5-5.0

Reticulocyte count

% 0.5-1.5 0.5-1.5

Factors necessary for Erythropoiesis.Factors necessary for Erythropoiesis.

A] General FactorsA] General Factors 1] Diet-Protein is essential for synthesis of Globin in of 1] Diet-Protein is essential for synthesis of Globin in of

HaemoglobinHaemoglobin Iron-essential for heam productionIron-essential for heam production Others-Cu, Mg, Cobalt, Ca etc.Others-Cu, Mg, Cobalt, Ca etc.

2] Hypoxia-hypoxia causes Liberation of hormone Erythropoietin 2] Hypoxia-hypoxia causes Liberation of hormone Erythropoietin which stimulate bone marrow for Erythropoiesiswhich stimulate bone marrow for Erythropoiesis

3] Erythropoietin3] Erythropoietin 4] Endocrine gland- Adrenal Gland, Pituitary Gland, Thyroid 4] Endocrine gland- Adrenal Gland, Pituitary Gland, Thyroid

Gland.Gland.

B] Maturation factorsB] Maturation factors 1] Vit. B121] Vit. B12 2] Folic Acid2] Folic Acid 3] Intrinsic Factor of Castle-It helps in absorption of Vit. B12 from 3] Intrinsic Factor of Castle-It helps in absorption of Vit. B12 from

gut and thus indirectly help in maturation.gut and thus indirectly help in maturation.

Classification of Anemia Classification of Anemia

Morphological & Aetiological ClassificationMorphological & Aetiological Classification

Morphological classification Morphological classification Based mainly on MCV & MCHC. MCH may be included Based mainly on MCV & MCHC. MCH may be included

1.Microcytic Hypochromic aneamia 1.Microcytic Hypochromic aneamia MCV, MCHC & MCH are below normal MCV, MCHC & MCH are below normal E.g. – IDA, thalassaemia, anaemia of chronic diseases E.g. – IDA, thalassaemia, anaemia of chronic diseases

 

 

2. Macrocytic anaemia 2. Macrocytic anaemia MCV is above normal . MCHC is normalMCV is above normal . MCHC is normal E.g. megaloblastic anaemia E.g. megaloblastic anaemia

3. Normocytic Normochromic anaemia 3. Normocytic Normochromic anaemia MCV, MCHC MCH are within normal range MCV, MCHC MCH are within normal range E.g. acute blood loss, haemolytic anemia E.g. acute blood loss, haemolytic anemia

Aetiological ClassificationAetiological Classification

This classification is based on pathophysiology & This classification is based on pathophysiology & cause cause

Impaired RBC production Impaired RBC production Hemolytic anemia Hemolytic anemia Blood Loss Blood Loss

Impaired RBC production Impaired RBC production

A. Deficiency of essential nutrients (Deficiency anaemia) A. Deficiency of essential nutrients (Deficiency anaemia) Iron deficiency – most common cause Iron deficiency – most common cause Vitamin B12 deficiency Vitamin B12 deficiency Folic acid deficiency Folic acid deficiency Combined deficiencyCombined deficiency

Others – protein calorie malnutrition , vitamin C deficiencyOthers – protein calorie malnutrition , vitamin C deficiency

B. Depression of erythropoiesis B. Depression of erythropoiesis Anemia of chronic disease – Chronic renal failure . Liver Anemia of chronic disease – Chronic renal failure . Liver

diseases, Malignancy diseases, Malignancy Invasion of bone marrow – leukaemia , secondary carcinoma Invasion of bone marrow – leukaemia , secondary carcinoma Aplastic anemiaAplastic anemia

B. Haemolytic anemia B. Haemolytic anemia Intracorpuscular defectIntracorpuscular defect Extracorpuscular defect Extracorpuscular defect

C. Blood Loss C. Blood Loss Acute Blood loss – loss of large volume of blood Acute Blood loss – loss of large volume of blood

over a short period over a short period Chronic blood loss e.g hookworm infestation, Chronic blood loss e.g hookworm infestation,

bleeding peptic ulcer, piles, menorrhagia bleeding peptic ulcer, piles, menorrhagia

Clinical features of anemia Clinical features of anemia Tiredness , Fatigue Tiredness , Fatigue Lethargy Lethargy PalpitaionPalpitaion Pallor is the most important physical sign Pallor is the most important physical sign

Laboratory diagnosis of anemia Laboratory diagnosis of anemia Hb estimation Hb estimation Diagnosis of Morphological type of anaemia Diagnosis of Morphological type of anaemia Diagnosis of aetiological type of anemia – Diagnosis of aetiological type of anemia –

discussed under individual type of anemia discussed under individual type of anemia

Packed cell volume (PCV)Packed cell volume (PCV) Is the volume of red cells in relation to that of whole blood Is the volume of red cells in relation to that of whole blood

PCV = MCV X red cell count PCV = MCV X red cell count

Normal values Normal values 40 – 45 % male 40 – 45 % male 37- 47 % female 37- 47 % female

MCV (Mean corpuscular volumes )MCV (Mean corpuscular volumes ) Indicates the average volume red cells Indicates the average volume red cells Normal 76 - 96 fl (femolitre)Normal 76 - 96 fl (femolitre)

MCH (mean corpuscular hemoglobin ) MCH (mean corpuscular hemoglobin ) Indicates average weight of Hb contained in each cell Indicates average weight of Hb contained in each cell Does not take into count cell sizeDoes not take into count cell size Obtained by dividing Hb by red cell /liter & multiplied by 10Obtained by dividing Hb by red cell /liter & multiplied by 101313

If Hb 15g/dlIf Hb 15g/dl Red cell – 5X10Red cell – 5X101212/L/L

MCH = 15X10MCH = 15X101313 / 5X10 / 5X101212 = 30 pg = 30 pg Normal 27-32 pg Normal 27-32 pg

MCHC (mean corpuscular haemoglobin concentration) MCHC (mean corpuscular haemoglobin concentration) Indicates the average concentration of Hb within average red Indicates the average concentration of Hb within average red

cells cells Usually 3 times higher that the whole blood Hb conc.Usually 3 times higher that the whole blood Hb conc. Obtained by dividing Hb by PCV /literObtained by dividing Hb by PCV /liter

If Hb 15g/dlIf Hb 15g/dl PCV – 0.45l/lPCV – 0.45l/l

MCHC = 15/0.45 = 33.3g/dl MCHC = 15/0.45 = 33.3g/dl Normal – 31-35 g/dl Normal – 31-35 g/dl

Diagnosis of morphological type of anemia Diagnosis of morphological type of anemia

1. Examination of peripheral blood film 1. Examination of peripheral blood film

2. Determination of Red cell absolute value 2. Determination of Red cell absolute value MCV & MCHC are below normal values – microcytic MCV & MCHC are below normal values – microcytic

hypochromic anemia hypochromic anemia MCV is above normal & MCHC is normal – macrocytic anemia MCV is above normal & MCHC is normal – macrocytic anemia MCV & MCHC are normal – normocytic normochromic aneamia MCV & MCHC are normal – normocytic normochromic aneamia

Iron deficiency anemiaIron deficiency anemia

Most common type of anemia Most common type of anemia

Total body iron content Total body iron content Male – upto 6gm Male – upto 6gm Female – 2gm Female – 2gm

80% of 80% of functional body iron functional body iron is found in hemoglobin, rest found is found in hemoglobin, rest found in myoglobin and iron-containing enzymes (e.g.catalase & in myoglobin and iron-containing enzymes (e.g.catalase & cytochromes). cytochromes).

The The iron storage pooliron storage pool, represented by hemosiderin and ferritin-, represented by hemosiderin and ferritin-bound iron (15% to 20% of total body iron.)bound iron (15% to 20% of total body iron.)

Stored iron is found mainly in the liver, spleen, bone marrow, Stored iron is found mainly in the liver, spleen, bone marrow, and skeletal muscle. and skeletal muscle.

Male Fem

Absorption Absorption Most absorbed in Duodenum Most absorbed in Duodenum

Causes /pathogenesi of iron deficiencyCauses /pathogenesi of iron deficiency

1. Inadequate iron intake 1. Inadequate iron intake Nutritional deficiency – deficient diet Nutritional deficiency – deficient diet

2. Impaired absorbtion – coeliac disease, tropical sprue, 2. Impaired absorbtion – coeliac disease, tropical sprue, gastrectomy or gastro-enterostomy gastrectomy or gastro-enterostomy

Causes /pathogenesi of iron deficiencyCauses /pathogenesi of iron deficiency

3. Increased physiological demand 3. Increased physiological demand During period of growth in children During period of growth in children During reproductive life in female – menstruation, During reproductive life in female – menstruation,

pregnancy, parturation & lactation increase the physiological pregnancy, parturation & lactation increase the physiological requirement fro iron requirement fro iron

4.Chronic blood loss – the gastrointestinal tract (e.g., peptic 4.Chronic blood loss – the gastrointestinal tract (e.g., peptic ulcers, colonic cancer, hemorrhoids, hookworm disease) or ulcers, colonic cancer, hemorrhoids, hookworm disease) or the female genital tract (e.g., menorrhagia, cancers) the female genital tract (e.g., menorrhagia, cancers)

Laboratory diagnosis of IDALaboratory diagnosis of IDA

Investigation & findingsInvestigation & findings

1. Blood Picture 1. Blood Picture Hb – Variably reduced Hb – Variably reduced Blood film – hypochromic, microcytic, anisocytosis. Blood film – hypochromic, microcytic, anisocytosis.

PoikilocytosisPoikilocytosisin severe cases target, elliptical, oval & pencil cellsin severe cases target, elliptical, oval & pencil cells

Haematocrit – reduced Haematocrit – reduced MCV – reduced(microcytosis) MCHC – reduced (hypochromic) MCV – reduced(microcytosis) MCHC – reduced (hypochromic)

& MCH is reduced & MCH is reduced

2. biochemical findings (confirm IDA)2. biochemical findings (confirm IDA) Serum iron - reduced Serum iron - reduced Serum ferritin - reducedSerum ferritin - reduced Total iron binding capacity – increased Total iron binding capacity – increased Percentage saturation of iron binding protein – decreased Percentage saturation of iron binding protein – decreased

3. Bone marrow 3. Bone marrow Although erythropoietin levels are increased, the marrow Although erythropoietin levels are increased, the marrow

response is blunted by the iron deficiency, and thus the marrow response is blunted by the iron deficiency, and thus the marrow cellularity is usually only slightly increasedcellularity is usually only slightly increased

Diagnostic criteria includeDiagnostic criteria include Anemia, hypochromic and microcytic red cell indices, low serum Anemia, hypochromic and microcytic red cell indices, low serum

ferritin and serum iron levels, low transferrin saturation, ferritin and serum iron levels, low transferrin saturation, increased total iron-binding capacity, and, ultimately, response increased total iron-binding capacity, and, ultimately, response to iron therapyto iron therapy

4. Further Investigation 4. Further Investigation Stool examination for Stool examination for

Ova of hookworm & Ova of hookworm & Occult blood Occult blood

Urine examination for haematuria Urine examination for haematuria Other investigations depending on clinical findings Other investigations depending on clinical findings

Megaloblastic aneamia Megaloblastic aneamia MA are characterized by formation of morphologically MA are characterized by formation of morphologically

abnormal (enlarged) nucleated red cell precursors called abnormal (enlarged) nucleated red cell precursors called megaloblasts in the bone marrow. megaloblasts in the bone marrow.

The change occurs due to deficiency of vitamin B12 or folate The change occurs due to deficiency of vitamin B12 or folate

Vitamin BVitamin B1212 Abundant in all animal foods, including eggs and dairy Abundant in all animal foods, including eggs and dairy

products, and is resistant to cooking and boiling. products, and is resistant to cooking and boiling. Even bacterial contamination of water and non animal Even bacterial contamination of water and non animal

foods can provide adequate amounts. foods can provide adequate amounts. It is stored in the liver, which normally contains reserves It is stored in the liver, which normally contains reserves

that are sufficient to support bodily needs for 5 to 20 yearsthat are sufficient to support bodily needs for 5 to 20 years As a result, deficiencies due to diet are rare and are As a result, deficiencies due to diet are rare and are

virtually confined to strict vegansvirtually confined to strict vegans

Metabolism of vitamin B12Metabolism of vitamin B12 Peptic digestion release dietary vitamin Peptic digestion release dietary vitamin

BB1212, ,

Binds to salivary BBinds to salivary B1212-binding proteins -binding proteins called called R binders.R binders.

R-BR-B1212 complexes transported to complexes transported to duodenum duodenum

Processed by pancreatic proteases to Processed by pancreatic proteases to releases Breleases B1212,,

Attaches to intrinsic factor (gastric juice) Attaches to intrinsic factor (gastric juice) The intrinsic factor-BThe intrinsic factor-B1212 complex passes complex passes

to the distal ileum to the distal ileum Attaches to the epithelial intrinsic factor Attaches to the epithelial intrinsic factor

receptors - absorption of vitamin Breceptors - absorption of vitamin B1212. .

BB1212 bound to transport proteins called bound to transport proteins called transcobalamins,transcobalamins, which then deliver it which then deliver it to the liver and other cells of the body. to the liver and other cells of the body.

Causes of Megaloblastic AnemiaCauses of Megaloblastic Anemia Vitamin B12 Deficiency Vitamin B12 Deficiency

Decreased intakeDecreased intake Inadequate diet, vegetarianismInadequate diet, vegetarianism

Impaired absorptionImpaired absorption Intrinsic factor deficiency - Pernicious anemia, GastrectomyIntrinsic factor deficiency - Pernicious anemia, Gastrectomy Malabsorption statesMalabsorption states Diffuse intestinal disease e.g. lymphomaDiffuse intestinal disease e.g. lymphoma Ileal resection, ileitisIleal resection, ileitis Competitive parasitic uptake - Fish tapeworm infestationCompetitive parasitic uptake - Fish tapeworm infestation Bacterial overgrowth in blind loops and diverticula of bowelBacterial overgrowth in blind loops and diverticula of bowel

Increased requirementIncreased requirement Pregnancy, hyperthyroidism, disseminated cancerPregnancy, hyperthyroidism, disseminated cancer

Folate metabolismFolate metabolism Best sources - fresh uncooked vegetables and fruits. Best sources - fresh uncooked vegetables and fruits. The principal site of intestinal absorption is the upper third of The principal site of intestinal absorption is the upper third of

the small intestinethe small intestine Conversion from dihydrofolate to tetrahydrofolate by the Conversion from dihydrofolate to tetrahydrofolate by the

enzyme dihydrofolate reductase is particularly important.enzyme dihydrofolate reductase is particularly important. Tetrahydrofolate involved in the synthesis of purines and Tetrahydrofolate involved in the synthesis of purines and

thymidylate, the building blocks of DNA, thymidylate, the building blocks of DNA,

Megaloblastic anemia Megaloblastic anemia Folic Acid DeficiencyFolic Acid Deficiency

Decreased intakeDecreased intake Inadequate diet—alcoholism, infancyInadequate diet—alcoholism, infancy

Impaired absorptionImpaired absorption Malabsorption statesMalabsorption states Intrinsic intestinal diseaseIntrinsic intestinal disease

Increased metabolismIncreased metabolism Anticonvulsants, oral contraceptivesAnticonvulsants, oral contraceptives

Increased lossIncreased loss HemodialysisHemodialysis

Increased requirementIncreased requirement Pregnancy, infancy, disseminated cancer, markedly increased Pregnancy, infancy, disseminated cancer, markedly increased

hematopoiesishematopoiesis Impaired useImpaired use

Folic acid antagonists – e.g.MethotrxateFolic acid antagonists – e.g.Methotrxate

Pathogenesis of Megaloblastic anemia Pathogenesis of Megaloblastic anemia Deficiency of Vit B12/folic acid Deficiency of Vit B12/folic acid Impairment of DNA synthesis, Impairment of DNA synthesis, Results in a delay in nuclear maturation and cell division. Results in a delay in nuclear maturation and cell division. Synthesis of RNA and cytoplasmic elements proceeds at a Synthesis of RNA and cytoplasmic elements proceeds at a

normal rate normal rate Hematopoietic precursors show Hematopoietic precursors show nuclear-cytoplasmic nuclear-cytoplasmic

asynchronyasynchrony Undergo apoptosis in the marrow (ineffective Undergo apoptosis in the marrow (ineffective

hematopoiesis)hematopoiesis)

Laboratory diagnosis of MALaboratory diagnosis of MA

Blood Blood Hb– reduced Hb– reduced Blood film Blood film

RBC- many oval macrocytes, Anisocytosis, poikilocytosis, RBC- many oval macrocytes, Anisocytosis, poikilocytosis, Polychromatic & stippled cells, howell-jolly bodies Polychromatic & stippled cells, howell-jolly bodies

White cells – hypersegmented neutrophils are always White cells – hypersegmented neutrophils are always present (4-9 lobes)present (4-9 lobes)

Megaloblastic blood compared to normal blood hypersegmented neutrophil with a six-lobed nucleus

Haematocrit (PCV)– reduced Haematocrit (PCV)– reduced Red cell count – reduced Red cell count – reduced MCV is high, MCH is high, MCHC is normal MCV is high, MCH is high, MCHC is normal WBC – leucopenia (neutropenia)WBC – leucopenia (neutropenia) Platelets – thrombocytopenia Platelets – thrombocytopenia Reticulocyte count – increased Reticulocyte count – increased

2. Biochemical findings 2. Biochemical findings Serum iron & ferritin – increased Serum iron & ferritin – increased Serum bilirubin – may be slightly increased in Vit B12 Serum bilirubin – may be slightly increased in Vit B12

deficiency deficiency Lactate dehydrogenase – increased Lactate dehydrogenase – increased Male Fem

3. Bone marrow 3. Bone marrow Cellularity – Hypercellular (increased numbers of Cellularity – Hypercellular (increased numbers of

megaloblasts)megaloblasts) M:E ratio is reduced or even reversedM:E ratio is reduced or even reversed Erythropoiesis - Megaloblastic erythropoiesis Erythropoiesis - Megaloblastic erythropoiesis Granulopoiesis is active – giant metamyelocyte with u Granulopoiesis is active – giant metamyelocyte with u

shaped nucleusshaped nucleus Iron in large amount. Sideroblast – increased Iron in large amount. Sideroblast – increased

A to C, Megaloblasts-various stages of differentiation

4. Special tests for vitamin B12 deficiency 4. Special tests for vitamin B12 deficiency Serum vitamin B12 assay Serum vitamin B12 assay Schilling test – detects ability of the body to absorb vit B12 Schilling test – detects ability of the body to absorb vit B12

after correction.after correction.Radioactive cobalt labeled vit B12 is used for the test . A Radioactive cobalt labeled vit B12 is used for the test . A small oral dose is given . Radioactivity in the urine is small oral dose is given . Radioactivity in the urine is measured measured

Methylmelonic acid excretion in urine - increased Methylmelonic acid excretion in urine - increased Therapeutic trail - Response to vit B12 administration Therapeutic trail - Response to vit B12 administration

5. Special Tests for folate deficiency 5. Special Tests for folate deficiency Serum folate assay Serum folate assay Red cell folate assay Red cell folate assay Theurapeutic trail - Response to folic acid administration Theurapeutic trail - Response to folic acid administration

Pernicious anemia Pernicious anemia

PA is a vitamin B 12 deficiency megaloblastic anaemiaPA is a vitamin B 12 deficiency megaloblastic anaemia

Pathogenesis Pathogenesis PA occurs due to failure of secretion of Intrinsic factor by PA occurs due to failure of secretion of Intrinsic factor by

the stomach due to permanent gastric atrophy the stomach due to permanent gastric atrophy Vit B12 in food not absorbed (gastrectomy, resection of Vit B12 in food not absorbed (gastrectomy, resection of

ileum )ileum )

Special tests Special tests Pentagastrin fast achlohydriaPentagastrin fast achlohydria Anti-intrinsic factor & anti-parietal cell antibodies in serum Anti-intrinsic factor & anti-parietal cell antibodies in serum

Diagnosis is made by Diagnosis is made by (1) low serum vitamin B(1) low serum vitamin B1212 levels, levels, (2) normal or elevated serum folate levels, (2) normal or elevated serum folate levels, (3) serum antibodies to intrinsic factor, (3) serum antibodies to intrinsic factor, (4) moderate to severe megaloblastic anemia, (4) moderate to severe megaloblastic anemia, (5) leukopenia with hypersegmented granulocytes, and (5) leukopenia with hypersegmented granulocytes, and (6) a dramatic reticulocytic response (within 2-3 days) to (6) a dramatic reticulocytic response (within 2-3 days) to

parenteral administration of vitamin Bparenteral administration of vitamin B1212..