Microcytic, Hypochromic Anemias

Question 1

Anemia Definition

What is it correlated with?

Answer 1

deficiency of oxygen delivery to the tissues / healthy red blood cells

Low RBC Count
Low hematocrit
Low Hemoglobin

Question 2

Anemia is classified by:

Answer 2

Physiology
- symptoms, bone marrow response

Morphology
- visual interpretation of peripheral smear
- RBC indices: MCV, MCHC, MCH

Question 3

Microcytic, hypochromic anemias definition

Answer 3

group of red cell disorders that involve a defect in hemoglobin synthesis and can produce RBCs that are:

Microcytic: < 6 um
(often MCV <80fL

Hypochromic = CAP >3 um
(often MCHC <32%)

Question 4

Deficiency of iron

Answer 4

IDA - iron deficiency anemia

• Majority
• Most common anemia

Question 5

Abnormal utilization of iron

Answer 5

• Anemia of chronic disease
• Sideroblastic Anemia

Question 6

Abnormal heme synthesis

Answer 6

Poryphyrias

Question 7

Abnormal globin chain synthesis

Answer 7

Thalassemia

Question 8

Iron (Fe)

Answer 8

Iron is essential for life
- makes hemoglobin
- essential mineral our body needs

Question 9

Iron can be classified in two categories

Answer 9

Heme iron

Non heme iron

Question 10

Heme iron

Answer 10

complexed into a porphyrin ring to form heme ring of hemoglobin

Question 11

non-heme iron

Answer 11

• Any iron outside of hemoglobin
• **Transfer and storage compounds **
• RBC inclusions

Question 12

Examples of non-heme iron; transfer and storage compounds

Answer 12

Transferrin

Ferritin

Hemosiderin

Question 13

Transferrin

Answer 13

CARRIER protein

• carrier protein for serum iron
• composed of beta globulin
• made in the liver

Question 14

Ferritin

Answer 14

STORAGE

• Water soluble
• Storage pools of bone marrow and liver
• Easily mobilized
• Serum Ferritin - proportional to iron stores in liver and BM

Question 15

Hemosiderin (harder to access)

Answer 15

STORAGE

• Water insoluble
• lysosomal membranes of macrophages (where they are stored)
• Precipitated aggregates of ferritin
• Long term-storage (last resort)

Question 16

Ferritin vs Hemosiderin

Answer 16

Hemosiderin has an extra phosphate

Question 17

Non heme iron in RBC

Answer 17

inclusions terminology
- Wright stained - pappenheimer bodies
- Prussian blue (iron stain) - siderotic granules

Cell terminology
- nulceated RBC - Sideroblasts
- Non-nucleated RBC - siderocytes

Question 18

wright stained RBC

Answer 18

pappenheimer bodies

Question 19

Prussian blue (iron stain)

Answer 19

Siderotic granules

Question 20

Nucleated RBC

Answer 20

sideroblasts

Question 21

non-Nucleated RBC

Answer 21

Siderocytes

Question 22

Iron absorption pathway

Answer 22

Iron in diet (Fe3+ and Fe2+)

Stomach (acidic pH)

Reduced to Fe2+

Intestines

Absorbed (Duodenum/Jejunum)

Blood (converted back to Fe3+)

Binds to Transferrin (carrier protein)

BM & Liver for storage (Ferritin)

Question 23

Iron is absorbed in

Answer 23

Duodenum/Jejunum which components of the small intestine

Question 24

Iron Sources

Answer 24

Meats (muscles)
Organ meats
Wheat Germ
Brewer’s yeast
Certain legumes
Milk/formula
Green veggies

Question 25

Green veggies (vitamin C and fructose)

Answer 25

enhance iron absorption

Question 26

Iron Minimal Daily Requirement (MDR)

Answer 26

Iron - loss of 1% of RBCs/day that must be replenished Most (95% in adults) iron comes from recycling senescent (old) RBCs. -- Remaining approx. 5% needs to come from diet Additional Loss of iron: Normal conditions - sweating, stool. menstruation

Question 27

Serum Iron (Analysis)

Answer 27

Transferrin - bound Iron Normal Range: 50-150 ug/dL

Question 28

TIBC - Total Iron Binding Capacity (analysis)

Answer 28

Availability of iron binding sites on Transferrin Normal Range: 250-450 ug/dL

Question 29

Transferrin % Saturation

Answer 29

Amount of iron bound in plasma/serum Normal Range: 20-50%

Question 30

Serum Ferritin

Answer 30

Proportional to amount of iron stored (Liver and BM - Acute phase reactant) Normal Range Male: 20-250 ug/dL Normal Range Female: 10-120 ug/dL

Question 31

IDA - Most common anemia

Answer 31

State in which body iron stores are depleted

Question 32

IDA causes

Answer 32

Blood loss (most common cause in western world) - Menstruation in females - GI bleed in Males Dietary insufficiency - Increased need - pregnancy /infants - lack in diet (3rd world) Absorption issue - Malabsorption - lack of gastric acids (gastrectomy, gastic bypass), or problem at absorption site (IBS, Celiac Disease) Many more

Question 33

IDA stage 1

Answer 33

Iron Depletion - Iron stores in the bone marrow are depleted (low ferritin) - our body compensated by increasing mucosal absorption of iron and producing more transferrin (increased TIBC) - CBC and RBC morphology = normal - Completely asymptomatic

Question 34

IDA stage 2

Answer 34

Iron Deficient Erythropoiesis - Plasma iron level drops (low serum iron) - CBC (Hgb and Hct) low -- more microcytic and hypochromic - RBC Morphology = slightly presentation of microcytic hypochromia

Question 35

IDA stage 3

Answer 35

Iron Deficiency Anemia - RBCs are severely deficient in iron - Hemoglobin formation is delayed - CBC (Hgb and Hct) marked Low - less O2 delivery to cells - EPO levels increase - Overt symptoms - RBC morphology = microcytic, hypochromic RBCs - possible to see reticulocytes, target cells and elliptocytes

Question 36

IDA clinical features Typical symptoms

Answer 36

Typical Symptoms: - Fatigue/Lethargy - Pallor - Vertigo - Dyspnea - Cold Intolerance

Question 37

IDA clinical features Miscellaneous Symptoms

Answer 37

Pica - Pagophagia - Geophagia Koilonychia

Question 38

Pica

Answer 38

abnormal cravings

Question 39

Pagophagia

Answer 39

craving for ice

Question 40

Geophagia

Answer 40

Craving for dirt, clay

Question 41

Koilonychia

Answer 41

spoon nails

Question 42

Answer 42

Microcytic, Hypochromic RBC

Question 43

IDA Lab Findings - Peripheral Smear

Answer 43

Microcytic, Hypochromic RBCs (large central pallor) Mild to moderate anisopokilocytosis (variation in size/shape) Additional Possibilities: - slight reticulocytosis (polychromasia) - accelerated erythropoiesis - target cells -Elliptocytes

Question 44

IDA Lab Findings - Iron Studies

Answer 44

Low serum ferritin (FOUND IN ALL IDA STAGES) High TIBC Low Serum Iron Low % Transferrin Saturation

Question 45

LOW serum ferritin

Answer 45

FOUND IN ALL IDA STAGES

Question 46

IDA lab findings - Bone Marrow

Answer 46

Usually not indicated for testing Mild to moderate erythroid hyperplasia. low M:E Poorly hemoglobinized pre-cursors with scanty cytoplasm Hemosiderin absent

Question 47

Answer 47

IDA bone marrow

Question 48

IDA treatment

Answer 48

Iron supplements - oral tables or drops (infants/children) - infusions (absorption issue) Severe cases ( significantly low hemoglobin) - transfusion