Anemia approach for clinical year medical students

1. D R . S E G E N E T B I Z U N E H
A S S I S T A N T P R O F E S S O R O F I N T E R N A L
M E D I C I N E
U N I V E R S I T Y O F G O N D A R
Approach to anemia and
specific anemia's
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2. Important to remember:
 Anemia is not a single disease by itself.
 Need to look for the underlying cause !
 Its diagnosis is not that simple !!
 Its very common and important in our practice.
 Rx. depends on the cause.
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3. ERYTHROPROSIS : Erythron
 Erythron is the machinery of RBC production.
 EPO, IL, Growth factors, Cytokines – stimulate it.
 Hypoxia is strong stimulus for the Erythron.
 Its functioning is influenced by:
1. Normal renal production of EPO
2. A functioning Erythroid marrow
3. An adequate supply of substrates for Hb production
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4. Let us meet the Grand Parents !
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5. Normal Red Cells
No nucleus, Enzyme
packets
Biconcave discs – Haem + Gl
Center 1/3 pallor
Pink cytoplasm (Hb filled)
Cell size 7 - 8 µ - capill. 2 µ
100-120 days life span
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6. The Factory – Bone Marrow
Produces 1% of RBC/day
 Vast potential to increase
production by > 5 fold
75% of marrow for WBC
25% of BM for Red cells
Erythrod / Granulocyte Ratio 1:3
E:G ratio increased in Anaemia
Large white areas are marrow fat
40%-50%
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7. ERYTHROPROTINE
Produced largely in the kidney(>90%) and to a lesser
extent in the liver(<10%)
Hypoxia is the main stimulus
Acts through its receptor ( EpoR) in coordination
with other factors
Hypoxia Inducible Factor(HIF)
Affects the growth and differentiation of RBC
progenitors especially the terminal events(CFU-E)
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8. Hemoglobin (Hb)
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9. DEFINITION
 Anemia can be defined precisely
as the absolute reduction in the
number of circulating RBC or
reduction in RBC volume as
determined by measuring RBC
volume or mass.
 Normal ranges for HGB, HCT, RBC
counts +/- 2SD in the population.
 Highly variable based on different
factors.
 WHO criteria for anemia
 Men= HGB < 13g/dL
 Women= HGB < 12g/dL
 Limitations
 Volume status
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10. Dehydration
Hct:Increased
Acute blood
loss(early)
Hct:unchanged
Chronic
anemia
Hct: Low
Increased
plasma
volume
Hct: Low
Hct
(a/b%):Normal
A
B
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11. Pertinent patient history
Hx or Sxs of anemia or medical condition related to
anemia
Duration
Family history of anemia/ethnicity/country
Blood loss/ previous transfusion
Hx of pregnancy/ Detailed menstrual hx
Dietary hx
Use of medication & exposure to chemicals
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12. REVIW OF SYMPTOMS
 Decreased oxygen delivery to tissues
 Exertional dyspnea, Fatigue
 Hypovolemia
 Fatiguablitiy, postural dizziness,
lethargy, hypotension, shock and
death
 GI-anorexia, chronic diarrhea,
hematemesis or melena
 CVS- Life threatening: heart failure,
angina, myocardial infarction
 GUS- menstrual irregularities, loss
of libido
 Neuromuscular system- headache,
tinnitus, vertigo, dizziness, lassitude,
cramps, visual impairment,
paresthesia, dementia, behavioural
changes
 Nutritional status ( BMI)
 Postural hypotension/tachycardia
 Skin/MM: Pallor, icterus, angular
stomatitis, atrophy of tongue papillae,
glossitis, koilonychia, palmar crease
pallor, leg ulcers, petechiae
 CVS- Wide PP, tachycardia, bounding
pulse, hemic murmur (P2 site), S3
gallop
 Abdominal- organomegaly, PR
examination
 GUS-PV examination
 LGS- LAP
 Musculoskeletal- Bone tenderness
 Neurologic- Mental status, gait,
position and vibration sense, reflexes,
fundoscopy for papilledema (acute
anemia), retinal hemorrhage (severe
anemia) and optic atrophy (cobalamin
def.)
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13. A) Initial Testing
1.Start with CBC: RBC count ,HGB,HCT, RBC count , WBC differential
 RBC Indices
 MCV (mean cell volume): Average volume of RBC (90±8fl)
MCV= Hct(%)x10/RBC count(1012/L)
 MCH (mean cell haemoglobin): Average weight of Hgb in RBCs (30±3pg/dl)
MCH=Hgb(gm/dl)x10/ RBC count(1012/L)
 MCHC(mean cell haemoglobin concentration):
Average(1012/L) concentration of hgb in each RBCs (33±3gm/dl)
 RDW
2.Reticulocyte count
3.Peripheral blood smear
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14. 2. Reticulocyte count
 Reflects bone marrow response to anemia
 Absolute reticulocyte count(ARC)=reported reticulocytes (%)xRBC count
 ARC= 25-75,000/µl, ARC>100,000/µl indicates hemolysis or
blood loss
 Corrected reticulocyte count (CRC) =ARC x Pts Hct/45(normal Hct)
 RPI (reticulocyte production index)
 Example
 Reticulocyte count (9%)
 Hb content(7.5 g/dl)
1. Correction for Anaemia
= 9 x (7.5 ÷ 15) = 9 x 0.5 = 4.5 %
2. Correction for increased life span
4.5 ÷ 2 = 2.25 %
3. Thus, the RPI is 2.25
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15. 3. Peripheral morphology
1. Size
 Microcytic (MCV<80), normocytic (MCV=80-100), macrocytic
(MCV>100)
 Anisocytosis : RBCs with increased variability in size (increased
RDW)
2.Colour
 Hypochromic: increase in size of central pallor (normal = less than
1/3 of RBC diameter)
 Polychromasia: increased reticulocytes (pinkish-blue cells)
 Increased RBC production by the marrow
3. Shape
 Poikilocytosis: increased proportion of RBCs of abnormal shape
4. RBC Inclusions
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16. Normochromic
Normocytic
Hypochromic
Microcytic
Anisocytosis, Poikilocytosis
Microspherocyte
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Tear drop
Bite cells
Oval macrocytes
Howell–Jolly bodies

17. B) Specific investigations
Bleeding
 Serial HCT, coagulation
studies
Iron Deficiency
 Iron Studies
Hemolysis
 Serum LDH, indirect
bilirubin, haptoglobin,
coombs,
Others-directed by
clinical indication
 hemoglobin electrophoresis
 B12/ folate levels
Bone Marrow Examination
 Cellularity (normally,
hematopoietic tissue
occupied 40-50% of marrow
space)
 Myeloid to erythroid ratio
(M:E ratio) (3-5:1)
 Morphological appearance of
RBC
 Other cell line abnormality
 Iron stain
 Histological Examination
 Culture for micro-organisms
 Flowcytometry & cytogenetic
studies
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18. A. Underlying mechanism B. Morphology of erythrocytes
Marrow production
defect
Infective
erythrocytosis
blood loss or increased
destruction
 Size (micro-, macro-,
normocytic)
 Shape (spherocytosis,
stomato-,...)
 Color (degree of
hemoglobinization:normo-
hypo-, hyperchromic)
Classification of Anemia
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19. Marrow production defect
(Hypoprolifrative)
Infective erythrocytosis
( Maturation defect)
 Normal M:E ratio(3-5:1)
 <2 RPI with unchanged
RBC morphology
 Early IDA
 ACD
 Marrow damage
 Low EOP
 M:E ratio=1:1
 RPI<2.5
 Increased reported reticulocyte
count but low corrected
reticulocyte count
 Marked morphologic change
 B/M= Erythriod Hyperplasia
1. Nuclear maturation defect
 Macrocytosis
 Alcoholism, VitB12 and folalte
deficiency , Drug , myelodysplasia
2. Cytoplasm maturation defect
 Microcytosis and hypochromic
 Iron deficiency, defect in Hg synthesis
Hypoprolifrative vs Maturation defect
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20. Blood loss Hemolytic
1. Acute blood loss:
 RPI normal
2. Sub acute blood loss:
 Modest reticulocytosis
3. Chronic blood loss:
 Manifest as IDA
 M:E ratio=1:1
 RPI>2.5
 Increased ARC and CRC
1. Extravascular ( High RIP) vs
Intravascular (Low/N RPI)
2. Inherited vs Acquired
3. Intracorpuscular defects VS
Extracorpuscular defects
Decrease RBC survival
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21. Morphology Approach
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22. Iron Deficiency Anemia(IDA)
 Iron is among the abundant minerals on earth.
Iron have several vital functions:
 Carrier of oxygen from lung to tissues
 Transport of electrons within cells
 Co-factor of essential enzymatic reactions:
 Neurotransmission
 Synthesis of steroid hormones
 Synthesis of bile salts
 Detoxification processes in the liver
 IDA is the most common cause of anemia throughout
the world and is the most common nutritional deficiency
worldwide.
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23. Iron Homeostasis
Physiology
 The average adult has 3.5 to 5.0 g of total iron.
 Is controlled by absorption rather than excretion.
 Normal iron loss is very small, amounting to less than 1
mg/day.
 There are no physiologic mechanisms that
regulate iron excretion, therefore losses must
be compensated for by an increased intake or
absorption.
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24. Iron Homeostasis…
DIETARY IRON:
 There are 2 types of iron in the diet; haem iron and non-haem iron:
 Ninety percent of iron consumed in the diet exists in the non-
haem form, while 10% is derived from haem.
 Haem iron is present in Hb containing animal food like meat, liver &
spleen.
 Non-haem iron is obtained from cereals, vegetables & beans.
 Breast milk and cow’s milk both contain about 0.5 to 1.0 mg of iron
per liter, but its bioavailability differs significantly.
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25. IRON ABSORPTION(Duodenum)
Fe3+ Fe2+
Storage iron
1000mg in male
500mg in femal 10/13/2021
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26. Inhibitors of Iron Absorption Promoters of Iron Absorption
 Dietary phenols & phytic
acids
 This compounds bind with
iron decreasing free iron in
the gut & forming complexes
that are not absorbed.
 Food fermentation and Ceral
milling reduce its phytic acid
content by 50%.
 Foods containing ascorbic acid and
muscle protein:
 Reduces iron from ferric to ferrous
forms, which increases its
absorption.
IRON ABSORPTION…
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27. Inhibitors of Iron Absorption Promoters of Iron Absorption
 Food with polyphenol compounds
 Cereals like sorghum & oats
 Vegetables such as spinach and
spices
 Beverages like tea, coffee, cocoa
and wine.
 A single cup of tea taken with meal
reduces iron absorption by up to
11%.
 Food containing phytic acid
 Cereals like wheat, rice, maize
& barely.
 Legumes like soya beans, black
beans & peas.
 Cow’s milk due to its high
calcium & casein contents.
 Foods containing
ascorbic acid:
 like citrus fruits, broccoli &
other dark green vegetables
NB:
 Some fruits inhibit the absorption
of iron although they are rich in
ascorbic acid because of their high
phenol content e.g strawberry,
banana and melon.
IRON ABSORPTION…
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28.  Contribution to energy intake
different cereals in Ethiopia
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29. IRON TRANSPORT
 Ferroportin: is the only known transporter that exports iron
from cells to plasma (and extracellular fluid).
 Transferrin: transports iron to erythroid precursors
that express transferrin receptors (TfR)
 Transferrin receptors and transferrin are then recycled
to the cell surface and circulation, respectively.
 Any remaining iron in the cell
 Combines with the protein apoferritin to generate ferritin.
 If the amount of apoferritin is insufficient, the remaining iron will
be deposited and stored in tissues as hemosiderin.
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30. Etiology
A. Chronic blood loss:
Each 1ml of RBC loss –1mg of iron loss
1. GI blood loss:
 Men and post menopause
2 . Genitourinary tract:
 >80ml/cycle of menses
 As high as 1 mg/day with nephritic syndrome
3. Iatrogenic (nosocomial):
 Daily 40-70ml of phlobotomy
 Dialysis
4. Blood donation:
 Each whole bood donation remove 200mg of
iron
5. Cow’s milk: Hypersenstivity
6. Respiratory tract:
 Recurrent hemoptysis
B. Pregnancy and lactation
 Diversion of Iron to fetal and infant
erythrocytosis
C. Dietary iron deficiency
 Meat-poor diets
D. Malabsorption
 Atrophic and autoimmune gastritis
 Gastric surgery and celiac disease
E. Intravascular hemolysis
 PNH and mechanical valve
F. Genetic Factors
 Iron-refractory iron deficiency anemia
 Mutations in Tmprss6=inappropriately
increased hepcidin
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31. DIAGNOSIS OF IDA
 Clinical Manifestations
that may be unrelated to
Anemia
 Decreased Work Performance
 Infant and Childhood
Developmental Delay
 Restless leg syndrome in
adults
 Oral and Nasopharyngeal
Symptoms
 Hair Loss
 Pica
 Physical Findings
Angular stomatitis
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32. Laboratory studies
 Serum Iron Concentration(<30mg/dl): High turnover rate
 Timing of blood sample; Serum iron has a diurnal variation
 Hold drug that contain iron before blood sample.
 Iron-Binding Capacity(>400mg/dl):
 Measurement of the amount of transferrin in the blood
 Transferrin Saturation(<15%):
 Measure available iron for erythropoiesis
 Serum Ferritin(<30mg/dl): reflect total iron body store
 Acute phase reactant
 Erythrocyte Zinc Protoporphyrin; increase in disorder of heam synthesis
 Serum Transferrin Receptor; increase receptor synthesis in iron deficiency
 Reticulocyte Hemoglobin Content and percentage of hypochromic
Erythrocyte
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33. Cont…
BLOOD:
 RBC: Microcytosis,
hypochromia,
anisocytosis
poikilocytosis
 Reticulocytoctosis
 WBC
 Platelate
BONE MARROW
 High cellularity
 Mild to moderate
erythroid hyperplasia (25-
35%; N 16 – 18%)
 Absence of stainable iron
 Decreased both
hemosiderin and
sidroblast
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34. When iron is required for erythropoiesis
 The storage sites (mononuclear
phagocyte system) provide the
firstline of defense.
 Initially ferritin levels decrease
 This is followed by a decrease
in serum iron levels, and then
total iron binding
capacity(TIBC) increases
 The density of transferrin
receptors on erythroid
precursors increases two- to
fourfold
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35. Iron deficency - stages
 Prelatent (Negative iron balance)
 Reduction in iron stores without reduced serum iron levels.
 Hb (N), MCV (N), iron absorption (), transferin saturation (N),
serum ferritin (), marrow iron ()
 Latent (Iron deficient erythropiesis)
 Iron stores are exhausted, but the blood hemoglobin level remains
normal.
 Hb (N), MCV (N), TIBC (), transferrin saturation (),
serum ferritin (), marrow iron (absent)
 Iron deficiency anemia
 Blood hemoglobin concentration falls below the lower limit of
normal.
 Hb (), MCV (), TIBC (), serum ferritin (), transferrin
saturation (), marrow iron (absent)
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36. Differential diagnosis
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37. IRON DEFICIENCY ANEMIA CURE
Dietary iron: although haem iron is better absorbed
than inorganic iron, the amount of haem iron in meat is
very small.
ORAL: Iron salt VS Carbonly iron
 Avoid enteric coated and prolonged releases iron salts.
 Use only ferrous form:
 Dose ? 200 mg of elemental iron daily 1 hour before meal
 How long?
 4-8 wk then half of the dose for 6-9 months to restore iron reserve
 Absorption
 Is enhanced: vit C, meat, orange juice, fish
 Is inhibited: cereals, tea, milk
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38. IRON DEFICIENCY ANEMIA CURE
 PARENTERAL IRON SUBSTITUTION; indications
 Oral iron intolerance (nausea, diarrhoea)
 Patients on hemodialysis
 Negative oral iron absorption test
 Chronic uncorrectable bleeding
 Necessity of quick management; Hg < 6 g/dl
 Currently available preparations include iron sucrose, low-
molecular-weight iron dextran, ferric gluconate,
ferumoxytol, ferric carboxymaltose, and iron isomaltoside
 I.v only in hospital (risk of anaphilactic shock)
 I.m in outpatient department
NB: Each gram of hemoglobin contains 3.3 mg of iron
 Iron to be injected (mg) = (15 - Hb) x body weight (kg) x 3.3 + daily storage
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39. EXPERIMENTAL COMPOUNDS
EDTA (Ethylene Diamine Tetra-Acetate) molecule
has 4 negative charges to which any metal can
be attached to form stable complex.
Food is usually fortified by both Fe-EDTA & Na or
Ca EDTA.
Fe EDTA is stable in the acidic PH of the
stomach, but dissociate in the alkaline PH
of the duodenum releasing ferrous ions
ready to be absorbed.
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40. ADVANTAGES OF USING EDTA LIMITATIONS of EDTA USE
 Iron absorption is 6 times
greater than with ordinary
methods even in the
presence of inhibitors.
 No need to add vitamin C
or other promoters to
enhance iron absorption.
 No change in colour or
flavour of food with EDTA
even when stored for long
time
 EDTA fortification is 7 times
more expensive than
ordinary fortification using
iron salts.
 Health care providers have
little experience with this
new technique.
Cont..
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41. Anemia of inflammation
Refers to mild to moderately anemia (Hgb 7 to 12
g/dL) associated with chronic infections and
inflammatory disorders and some malignancies.
 The newer name, anemia of inflammation (AI):
 Reflective of the pathophysiology of Anemia of
chronic disease
 Includes anemia of critical illness: within days
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42. PATHOGENESIS
1. RED CELL DESTRUCTION:
 Human studies indicate that transfused AI erythrocytes
have a normal life span in normal recipients but
transfused normal erythrocytes have a decreased life
span in AI recipients.
 Macrophages prematurely remove aging
erythrocytes.
2. SUPPRESSIVE EFFECTS OF INFLAMMATION ON
ERYTHROPOIETIC PRECURSORS:
 TNF-α, IL-1, and the interferons, exert a
suppressive effect on erythroid colony formation.
3. INADEQUATE EPO SECRETION AND
RESISTANCE TO EPO:
 EPO-producing cell is inhibited by inflammatory
cytokines including TNF-α and IL-1.
 Patients with CRP greater than 50 mg/L reached
lower concentrations of Hgb than patients with
CRP less than 50 mg/L, despite higher doses of
erythropoiesis-stimulating agents.
IL-6-Hepcidin pathway
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43. Etiology
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44. LABORATORY FEATURES
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45. 10/13/2021
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46. MARROW IRON STAIN
Iron found in the marrow
in two forms:
1. Storage in macrophage
2. Functional iron in
nucleated RBC: Sidroblast.
IDA= Both sidroblast and
macrophage iron absent
AI= Sideroblast iron absent
with normal to increase
iron in macrophage
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47. Guideline Recommendations for Anaemia Management in
Patients with Cancer
ASCO/ASH
 Effective treatment of the underlying disease resolves
the anemia.
 Initiate epoetin in patients with Hb ≤10 g/dl (or
Hb >10 to <12 g/dl depending on clinical circumstances)
 SC 150 IU/kg three -times weekly; double dose in absence of
response (Hb increase <1–2 g/dl) after 4 weeks
 Reduce dose of EPO if:
 Hg reaches to avoid transfusion
 Hg increase exceeding 1g/dl in two weeks period to avoid EPO
exposure
 Insufficient evidence to support ‘normalisation’ of Hb >12 g/dl
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48. A Case…
A 30 years old male patient undergone dental
procedure with inhaled sedation.
After 16hrs of procedure CBC shows severe
leucopenia and thrombocytopina with mild
anemia.
PM NCNC, with estimated blood loss <100ml.
Marrow shows
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49. Macrocytic anemia
Megaloblastic
 Anemia is due to deficiency
of vitamin B12 and folic acid
30-50 % of all
macrocytic anemias
 More severe macrocytosis with
oval erythrocytes
 Usually MCV is >110
 Marrow shows nuclear
cytoplasmic asynchrony
 Erythroid lineage
 Myeloid lineage
 Reticulocyte index is not
increased
 Non-Megaloblastic
 The macrocytosis is not due to
vitamin B12 or folic acid
deficiency
 Less severe macrocytosis with
round erythrocytes
 Usually MCV is <110
 Increased Reticulocytes
 Pathophysiology unknown
 Increase in membrane lipids
 Alcoholism, Liver disease,
 Hypothyroidism,Aplastic anemia
 Artifact
 RBC clumping
 cold agglutinin disease
 Hyperglycemia
 RBC swelling
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50. Megaloblastic anemia
 A subclass of macrocytic anemia (under morphologic
classification)
 A subclass of anemias due to defective DNA synthesis
(pathogenetic classification)
 The common feature of all megaloblastic anaemias is a defect
in DNA synthesis that affects rapidly dividing cells in the
bone marrow and other tissues.
 The end result is cells with arrested nuclear maturation but
normal cytoplasmic development: so-called
nucleocytoplasmic asynchrony.
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51. Folic acid Vitamin B12
 Minimal daily intake is 50 micrograms.
 Absorption: Duodenum and Jejunum.
 Transportation: Weakly bound to
albumin.
 Body stores : are 5-10 mg (liver)
 Necessary for the production of the
RBC, WBC and platelets.
 If intake is reduced to 5
micrograms/day, megaloblastic
anemia will develop in ~4 months
 It is not synthesized in the body.
 Present in animal and vegetable
products.
 Asparagus, broccoli, spinach,
lettuce, lima beans (>1mg/100g )
 Liver, yeast, mushrooms,
oranges.
 Cooking depletes food of folate.
 Diary requirements: 1-2 µg daily.
 Absorption: in the distal ileum
 Transportation: Transcobalamine II,
which carry vitamin B12 to liver,
nerves and bone marrow.
 Microorganisms are the ultimate
origin of cobalamin
 It is efficiently reabsorbed from bile
 It is resistant to cooking and boiling
 Body stores 2-5mg (mostly in the liver)
 Depletion takes longer that folate
 It takes years to develop
megaloblastic anemia due to B12
deficiency
 Obtain it from animal food such
as liver, kidney, meat and dairy
products as milk and cheese.
Folic acid vs Vitamin B12
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52. Methylmalonyl -CoA-enzyme
Only Vit.B12
Methione synthase
Fotale + Vit.B12
Cobalamin – folate relationship
Adenosyl cobalamin
Methyl cobalamin
+
MTHF
polyglutamate synthase
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53. stomach
Enterohepatic
circulation
Ileum cells
Pancreas enzymes
Parietal cell
Duodenum
and jejunum
B12 in diet
R - B12
R- B12
B12
B12
IF
B12
TC II
B12
İleum
IF
IF - B12
IF – B12 complex requires
Calcium ions and a pH
around neutral.
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54. Folic acid deficiency B12 deficiency
 Increase demand :
 Pregnancy ,Lactation, Infancy
 Puberty and growth period
 Patients with chronic hemolytic
anemias and Disseminated cancer
 Decreased intake:
 Elderly, Lower socio economic
status, Chronic alcoholics
 Impaired absorption:
 Acidic food substances in foods like
legumes, beans
 Drugs like phenytoin, oral contraceptives
 Celiac disease which affect the gut
absorption
 Heat sensitive – more loss during cooking
 METABOLIC INHIBITION
 Decreased intake
 Veganism
 Impaired absorption
 Gastric
 Poor stomach acidity
 Gastrectomy
 Pernicious anemia
 Chronic pancreatitis
 Decreased trypsin and calcium
 Intestinal disease
 Ileal resection
 Ileal disease
 Chron’s disease
 Celiac sprue and tropical sprue
 Fish tapeworm
 Diphyllobothrium latum
 Blind loop
 Intestinal bacterial overgrowth
Folic acid vs Vitamin B12 deficiency
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55. Sequence of changes in megaloblastic anemia
1. Vitamin levels decrease with elevation of
metabolites
2. Neutrophil hypersegmentation
3. Oval macrocytosis in the peripheral blood
4. Megaloblastic changes in the marrow
5. Anemia and Ineffective erythropoiesis
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56. Clinical feature of Megaloblastic anemia
 Patients develop all general
symptoms and signs of the
anaemia.
 Knuckle pigmentation
 Angular stomatitis
 Atrophic glossitis- “beefy”
tongue
 Neurological disorders:
 Demylination of dorsal and
lateral spinal cord
 Dymylination of peripheral
and cranial nerves
 Deficiency during pregnancy
causes neural tube defect.
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57. CBC and peripheral morphology
Macrocytic anemia
MCV is usually >110 fL and often
>120 fL
Pancytopenia is seen in some cases
 Increased red cell breakdown due to
ineffective hematopoiesis
 Elvated bilirubin and LDH
Inclusions
Macro ovalocyts
Normal
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58. BONE MARROW
 Markedly hypercellular
 Myeloid : erythroid ratio
decreased or reversed
 Erythropoiesis :
MEGALOBLASTIC
 MEGALOBLAST
1. Abnormally large
precursor
2. Deeply basophilic royal
blue cytoplasm
3. Fine chromatin with
prominent nucleoli
4. Nuclear cytoplasmic
asynchrony
5. Abnormal mitoses
6. Maturation arrest
Normal
Megaloblast
Megaloblast
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59. Folate deficiency
B12 deficiency
 Folate, serum level (>4ng/dl)
 Reflects recent levels of ingestion
 Falsely increased with hemolysis
 <2ng/dl in the absence of anorexia or
starvation Dx folate deficiency
 2-4ng/dl
 RBC Folate
 Reflects stores (2-3 months)
 Will be decreased in B12 deficiency
 B12, serum level(>300pgdl)
 <200ng/l severe
 200-300 borderline
Laboratory
Serum methylmalonic acid and
homocystine levels may be more
sensitive
 B12 deficiency, both are elevated
sensitivity 94%, specificity 99%
Folate deficiency, only homocystine
levels are elevated
sensitivity 86%, specificity 99%
Schillings test:
Helps to identify the source of B12
deficiency
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60. Shilling Test
1. PART 1: Oral labeled B12 and
IM unlabeled B12 after 02 hr
to saturate tissue stores
2. 24h urine to assess absorption
>5% normal
<5% impaired
3. PART 2: Repeat with oral IF
if now normal =PA
if abnormal = malabsorption
4. Can continue with antibiotics to
look for bacterial overgrowth,
pancreatic enzymes for
exocrine insufficiency
Part 1 test result Part 2 test result Diagnosis
Normal -
Normal
or vitamin B12
deficiency
Low Normal
Pernicious
anemia
Low Low Malabsorption
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61. NB: With normal MCV around 25% patients
may have Megaloblastic anemia
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62. Pernicious Anemia
 Decreased secretion of intrinsic
factor due to gastric atrophy
and loss of parietal cells.
 Immunologically mediated,
autoimmune destruction of gastric
mucosa.
 More common in Northern European
descent greater than age 50
1. Adult: >60 years: Atrophic gastritis
 Gastric body and funds involved
 All gastric secretions are decresed
 Chief cells and parietal cells are lost
and intestinal metaplasia may occur
2. Juvenile: 10 - 20 years
3. Congenital : < 2 years
C/F
 Lemon colored skin premature gray person
Lab
 Three types of antibodies:
a) Type I antibody(75%) blocks vitamin
B12 and IF binding
b) Type II antibody (50%) prevents
binding of IF-B12 complex with ileal
receptors.
c) Type III antibody(85-90%) patients
– against specific structures in the
parietal cell
 Other autoimmune diseases
 In the absence of antibody level
 Serum gastrin level increase
 Decrease pepsinogen I
 Schilling’s test
 Endoscopy; look for Gastric Ca
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63. Treatment
 Folic acid
 1-5mg orally for one to four
months (or till macrocytic
anemia resolves)
 Why 4 moths till falte
depleted RBC eliminated.
 Folic acid will correct the
hematologic but not the
neurologic squeal of B12
deficiency.
 MUST rule out B12
deficiency: if patient
required long folic acid
therapy flow Clb level
yearly
 For pregnant 5mg folic acid
if history of NTD.
 Vit. B12
Cyanocobalamin :only IM avoid IV
least painful for the patient to inject
Use other preparation in smoker
Cheap
Methylcobalamin:can be given IM, Iv
and intraarticularly
More bioactive
Better choice for smokers
Hydroxocobalamin: use IV, IM very
painful
The most bioactive form
Retained longer in the body
For patients with cyanide poisoning
Restore body store need 8-10 dose
Life long B12 for PA
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65. Hemolytic anemia
 Hemolytic disorder decreased RBC survival.
 Hemolytic anemia: rate of RBC destruction exceed marrow RBC
production.
 Red cell survival : as low as 30 days may be tolerable
 If hemolysis is recurrent or persistent;
 Increased requirement folic acid
 Increased bilirubin production: gallstones.
 Hypersplenism : with consequent neutropenia and thrombocytopenia.
 Compensated Vs decompensated
 i.e., anemia may suddenly appear:
 Pregnancy, Folate deficiency, inadequate EPO production, An acute
infection
 Up to 25% of hemolytic anemias will present with a normal
reticulocyte count due to immune destruction of red cell precursors.
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66. Intravascular Hemolysis Extravascular Hemolysis
 The RBCs are lysed within the blood vessel:
 Such as by mechanical damage of a heart valve,
or because of complement fixation as PNH
 The hemoglobin is released into the blood and
immediately bound by haptoglobin for
clearance in the liver.
 If the hemolysis is too much, haptoglobin get
consumed and extra hemoglobin set free in the
circulation (that's why hemoglobinemia).
 This free hemoglobin reaches the kidney and get's
filtered and then reabsorbed in the form of Iron.
 Again if hemolysis is beyond the reabsorptive
capacity of the renal tubules, hemoglobin will
appear in the urine (hemoglobinuria, and
urinary hemosiderin appears).
 Because the fact that RBSs are lysed in the blood,
its LDH is released into the circulation raising it's
levels
 Schistocytes are essentially broken up and
fragmented RBCs.
 Excessive loss of iron
 RBC destroyed in spleen and live macrophage
 RBCs are coated with antibodies (AIHA)
 Abnormal shape of membrane
 Abnormal inclusion (such as Heinz bodies in G6PD)
Intravascular Versus Extravascular Hemolysis
Activation of
Complement
on RBC
Membrane
Physical or
Mechanical
Trauma to the
RBC
Toxic
Microenviron
ment of the
RBC
Paroxysmal
noctural
hemoglobinuria
Microangiopathi
c hemolytic
anemia
Bacterial
infections
Paroxysmal cold
hemoglobinuria
Abnormalities of
heart vessels
P. falciparum
infection
Transfusion
reactions
DIC Venoms
AHIA Acute drug
reaction in
G6PD
deficiency
Origin Anemias
Inherited RBC
Defects
Hemoglobinopathies
Enzyme deficiencies,
Membrane disorder
Acquired RBC
Defects
Megaloblastic
anemia, Vitamin E
deficiency in
newborns
Immunohemolytic
anemias
Autoimmune, Drug
induced, Some
transfusion reactions
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67. INHERITED HEMOLYTIC ANEMIAS
1. Membrane-cytoskeleton complex;
INHERITED vs ACQUIRED HEMOLYTIC ANEMIAS
The lipid layer
Proteins
Cytoskeleton
2.Hemoglobinopathies: disorders
affecting the structure, function, or production
of hemoglobin.
3. Enzymes is defective; Decrease ATP
production or failure to prevent oxidative damage
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68. 1- Abnormalities of RBC interior
a. Enzyme defects
b. Hemoglobinopathies & Thalassemia Maj
2-RBC membrane abnormalities
a. Hereditary spherocytosis, elliptocytosis etc
b. Paroxysmal nocturnal hemoglobinuria
c. Spur cell anemia
3- Extrinsic factors
a. Hypersplenism
b. Antibody : immune hemolysis
c. Traumatic & Microangiopathic hemolysis
d. Infections , toxins , etc
Hereditary
Acquired
Intracorpuscular Vs Extracorpuscular
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69. Hereditary spherocytosis (HS) Spherocyte
 Defective spectrin molecule
 Autosomal dominant or most severe
forms autosomal recessive
 Extra vascular hemolysis
 Jaundice, spleneomegally ,Gallstones
 Elevated MCHC suspect HS
 Osmotic fragility: RBC usceptible
to lysis in hypotonic media.
 Treatment :
 Delay splenectomy until puberty in
moderate cases or until 4–6 years of
age in severe cases.
 Cholecystectom: when clinically
indicated.
INHERITED HEMOLYTIC ANEMIAS
(Membrane-cytoskeleton complex )
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70. Glucose 6-phosphate dehydrogenase
(G6PD) deficiency
 In red cells it is the only source of NADPH
 NADPH glutathione (GSH)
defends these cells against oxidative
stress.
 The G6PD gene is X-linked
 400 million people have a G6PD deficiency
 Relative resistance to P. falciparum malaria
 Clinical manifestations:
 Neonatal jaundice
 AIHA as a result of triggers: fava beans,
infections, and drugs (Primaquine,
Cotrimoxazole, Ciprofloxacin)
 Tx: Regular folic acid supplements and avoid
the offending agent
INHERITED HEMOLYTIC ANEMIAS
(Enzymes is defective)
bite cells
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71. Thalassemias
 Genetic defect in hemoglobin
synthesis
  synthesis of one of the 2 globin
chains ( or )
 Imbalance of globin chain
synthesis leads to depression of
hemoglobin production and
precipitation of excess globin
(toxic)
 “Ineffective erythropoiesis”
 Ranges in severity from
asymptomatic to incompatible
with life (hydrops fetalis)
 Found in people of African, Asian,
and Mediterranean heritage
 Dx:
 Smear:
microcytic/hypochromic,
misshapen RBCs
 -thal will have an abnormal
Hgb electrophoresis (HbA2,
HbF)
 The more severe -thal
syndromes can have HbH
inclusions in RBCs
 Fe stores are usually elevated
 Tx:
 Mild: None
 Severe: RBC transfusions + Fe
chelation, Stem cell
transplants
INHERITED HEMOLYTIC ANEMIAS
(Hemoglobinopathies)
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72. Acquired Haemolytic Disorders
The acquired haemolytic disorders can be
sub-classified according to the nature of the
defect:
1. Haemolysis secondary to immune mechanisms.
2. Haemolysis secondary to infection.
3. Haemolysis secondary to physical damage.
4. Miscellaneous disorders
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73. Acquired Haemolytic Disorders
(IMMUNE HEMOLYTIC ANEMIA)
 If all of complement cascade is fixed to red cell, intravascular cell lysis
occurs.
 If complement is only partially fixed, macrophages recognize Fc receptor of Ig of
complement & phagocytize RBC, causing extravascular RBC destruction.
Clasfications:
1. Drug-Related Hemolysis
 Immune Complex Mechanism
 Quinidine, Quinine, Isoniazid
 “Haptenic” Immune Mechanism
 Penicillins, Cephalosporins
 True Autoimmune Mechanism
 Methyldopa, L-DOPA, Procaineamide, Ibuprofen
2. Alloimmune Hemolysis
 Hemolytic Transfusion Reaction
 Hemolytic Disease of the Newborn
3. Autoimmune Hemolysis
 Warm autoimmune hemolysis
 Cold autoimmune hemolysis
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74. Direct Antiglobulin Test Indirect Antiglobulin Test
 Looks for immunoglobulin &/or
complement of surface of red
blood cell (normally neither
found on RBC surface)
 Coombs reagent - combination of
anti-human immunoglobulin &
anti-human complement
 Mixed with patient’s red cells; if
immunoglobulin or complement
are on surface, Coombs reagent
will link cells together and cause
agglutination of RBCs
 Looks for anti-red blood cell
antibodies in the patient’s serum,
using a panel of red cells with
known surface antigens.
 Combine patient’s serum with
cells from a panel of RBC’s with
known antigens.
 Add Coombs’ reagent to this
mixture.
 If anti-RBC antigens are in
serum, agglutination occurs
Acquired Haemolytic Disorders
(IMMUNE HEMOLYTIC ANEMIA)
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75. IMMUNE HEMOLYTIC ANEMIA
(ALLOIMUNE HEMOLYSIS)
Hemolytic Transfusion Reaction
Caused by recognition of foreign antigens on
transfused blood cells
Several types
 Immediate Intravascular Hemolysis (Minutes) - Due to
preformed antibodies; life-threatening
 Slow extravascular hemolysis (Days) - Usually due to
repeat exposure to a foreign antigen to which there was a
previous exposure; usually only mild symptoms
 Delayed sensitization - (Weeks) - Usually due to 1st
exposure to foreign antigen; asymptomatic
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76. IMMUNE HEMOLYTIC ANEMIA
(AUTOIMMUNE HEMOLYSIS)
Due to formation of autoantibodies that attack
patient’s own RBC’s.
Further subdivided according to their maximum
binding temperature.
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77. Warm Type Cold Type
 Usually IgG antibodies
 Fix complement only to level
of C3.
 Immunoglobulin binding occurs
at all temperature ( body T)
 Fc receptors recognized by
macrophages.
 Hemolysis primarily
extravascular
 70% associated with other
illnesses
 Responsive to
steroids/splenectomy
 Rituximab together with
prednisone will become a first-
line standard.
 Most commonly IgM mediated
 Antibodies bind best at 0-4º c
 Fix entire complement
cascade
 Leads to formation of
membrane attack complex,
which leads to RBC lysis in
vasculature
 90% associated with other
illnesses
 Poorly responsive to steroids,
splenectomy; responsive to
plasmapheresis
IMMUNE HEMOLYTIC ANEMIA
(AUTOIMMUNE HEMOLYSIS)
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78. Diagnostic Approach to Hemolytic Anemias
Increased RBC Production
Increased RBC Destruction
COOMBS
(DAT) test
Immune
Hemolytic
Anemias
Peripheral blood smear
RBC Morphology
Lab
Investigation
Definitive
Diagnosis
Peripheral smear
Spherocytes
Fragmented RBC
Acanthocytes (spur cell)
Teardrop cell
Blister or “ bite” cells
RBC inclusions
Parasites
Inta Vs Extra Vascular
Increased LDH
Increased In.Bilirubin
Hemoglobinemia
Hemoglobinuria
Decreased haptoglobin
Hg electrophoresis
Genetic study
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