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Faculty of Medicine Dr. Tariq Aladily Faculty of Medicine Dr. Tariq Aladily THE UNIVERSITY OF JORDAN FACULTY OF MEDICINE DEPARTMENT OF PATHOLOGY INTRODUCTION TO ANEMIA Third year medical students First semester 2018/2019 Dr. Tariq Aladily

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Faculty of Medicine Dr. Tariq Aladily

Faculty of Medicine Dr. Tariq Aladily

THE UNIVERSITY OF JORDAN

FACULTY OF MEDICINE

DEPARTMENT OF PATHOLOGY

INTRODUCTION TO ANEMIA

Third year medical students

First semester

2018/2019

Dr. Tariq Aladily

Faculty of Medicine Dr. Tariq Aladily

RBC DISORDERS

• Lecturer: Dr. Tariq Al-Adaily

• Email: [email protected]

• Office: JUH- outpatient building

• 3rd floor, Hematology Lab

• Office hours: Wed 12-1

• Reference: Robbins Basic Pathology, 10th edition

Faculty of Medicine Dr. Tariq Aladily

Definition

• Reduction of oxygen transport capacity of blood, secondary to decrease in RBC mass to below average levels

• Leads to tissue hypoxia

• Practically, measure by Hemoglobin concentration, and Hematocrit (ratio of packed RBCs to total blood volume)

Faculty of Medicine Dr. Tariq Aladily

Adaptive changes

Generalized tissue hypoxia leads to

• Increased cardiac output

• Increased respiratory rate

• Increased red cell 2,3-diphosphoglycerate (DPG)

• Increased erythropoietin level (except in renal failure, anemia of chronic disease)

Faculty of Medicine Dr. Tariq Aladily

General Symptoms

• Pallor

• Dizziness

• Headache

• Fatigue

• Hypotension

• Tachypnea

• Tachycardia

Faculty of Medicine Dr. Tariq Aladily

Symptoms in special types

• Jaundice (hemolytic anemias)

• Pigmented gall bladder stones

• Growth retardation

• Skeletal deformity

• Secondary hemosiderosis, causing heart, renal & endocrine failure

Faculty of Medicine Dr. Tariq Aladily

Classification according to cause

1) Blood loss

2) Diminished RBC production

• Iron deficiency anemia

• Megaloblastic anemia

• Aplastic anemia

• Pure red cell aplasia

• Myelophthisic anemia

• Myelodysplastic syndrome

3) Increased destruction

(hemolytic anemia)

• Extrinsic factors (infection, antibody, mechanical)

• Intrinsic RBC abnormalities:

1) Hereditary (membrane, enzyme, Hg abnormalities)

2) Acquired (Paroxysmal nocturnal hematuria)

Faculty of Medicine Dr. Tariq Aladily

Classification according to morphology Blood film

• Size: normo, micro, macrocytic

• Color: normo, hypochromic

• Shape: anisopoikelocytosis (spherocytes, sickle, schistiocytes)

• Hypochromic microcytic anemia usually reflects impaired Hg synthesis

• Macrocytic anemia reflects stem cell disease and maturation

Faculty of Medicine Dr. Tariq Aladily

RBC indices

• Slight variation is present between labs, geographic areas

• Sex, age, race status have effect

• Red cell distribution width (RDW): the coefficient of variation in red cell volume

Faculty of Medicine Dr. Tariq Aladily

Anemia of acute blood loss • Symptoms are related to decreased intravascular volume,

might cause Hypovlemic Shock and death

• Body responds by shifting fluid from interstitial to intravascular space, causing dilutional anemia and hypoxia

• Erythropoietin secretion is stimulated, activating BM erythropoiesis

• Mature RBCs & Reticulocytes appear in blood after 5 days

• In internal hemorrhage, iron is restored from extravasated RBCs and used again in erythropoiesis, while in external hemorrhage, iron is lost

• The anemia is normochromic normocytic, with reticulocytosis

• Leukocytosis (secondary to stress)

Faculty of Medicine Dr. Tariq Aladily

Anemia of chronic blood loss

• Occurs when the rate of RBC loss exceeds regeneration

• Commonly seen in GI diseases (hemorrhoids, peptic ulcer, colon cancer) & gynecologic diseases (menorrhagea)

• Mostly associated with iron deficiency

• Appears as normochromic normocytic, or hypochromic microcytic

Faculty of Medicine Dr. Tariq Aladily

Hemolytic Anemia

• Normally, RBCs age is around 120 days, aged RBCs are engulfed by macrophages in spleen, liver and BM

• In Hemolytic anemia; premature destruction of RBCs, internal or external factors

• Extravascular hemolysis: results in increased phagocytic activity

• Intravascular hemolysis: occurs inside blood vessels

• Accumulation of Hg degradation products

• Increased: erythropoietin, serum lacate dehydrogenase (LDH), Retic count

• Secondary increased erythropoiesis

Faculty of Medicine Dr. Tariq Aladily

Extravascular Hemolysis

• Generally caused when the RBC has abnormal shape (less deformable) or coated with antibodies

• This prevents its normal movement in splenic sinusoids

• Prolonged time of RBCs passage attracts histiocytes to engulf them

• Free Hg from destructed RBCs binds Haptoglobin in serum, causing decreased level

• Hg within phagocytes is converted to bilirubin

• The triad of extravascular HA is: Anemia, splenomegaly and jaundice

Faculty of Medicine Dr. Tariq Aladily

Intravascular Hemolysis

• Less common • Caused by mechanical damage, microorganism,

exogenous toxins • Due to large amount of free Hg, haptoglobin is

cleared from the serum • free Hg in serum is oxidized to Methemoglobin

(metHg) • Excess free Hg and met Hg are excreted in urine

(hemoglobinuria) causing dark urine • Renal hemosiderosis may occur

Faculty of Medicine Dr. Tariq Aladily

THE END