Hypochromic/Microcytic Anemia

Question 1

Microcytic Anemia

Answer 1

Abnormal iron metabolism: Sideroblastic anemia, Iron deficiency anemia Anemia of chronic disease: Abnormal globin production, Thalassemia

Question 2

Microcytic Anemia Characteristics

Answer 2

Microcytic erythrocytes are indicated by MCV

Question 3

Iron Metabolism

Answer 3

Ferritin: a protein that stores and controls the release of iron Transferrin: an iron transport protein Total iron binding capacity: a measurement that shows the amount of iron that can be bound by transferrin Iron: important for cell growth and O2 transport Most of the iron in the body comes from recycled heme (85% iron)

Question 4

Iron Absorption

Answer 4

Nutritional supplementation is important Iron metabolism may be impaired: Chronic blood loss, Increased iron utilization When iron is consumed: Any Fe3+ is reduced to Fe2+, Absorbed by intestinal cells, Transported (transferrin) to marrow or stored in the liver (ferritin), Ferritin releases iron as needed

Question 5

Cause of Microcytosis

Answer 5

The size of a developing RBC is dependent upon hemoglobin production- Iron deficiency leads to poor hgb production

Question 6

Iron Deficiency Anemia

Answer 6

The most common anemia Causes: Dietary deficiency, Blood loss, Slow GI bleeding, Menstrual cycles, Hookworms, Dialysis, Intestinal malabsorption Increased needs: Pregnancy, Normal childhood growth

Question 7

Iron Deficiency Anemia Stages

Answer 7

1) Iron depletion: Ferritin iron stores are exhausted 2) Iron deficient erythropoiesis: Hgb is poorly formed in the absence of iron 3) Iron deficiency anemia: Development of microcytic, hypochromic anemia Associated lab tests: Decreased ferritin, Increased transferrin, Increased TIBC, Decreased serum iron, Elevated RDW

Question 8

Iron Deficiency Anemia Clinical Presentation

Answer 8

Spoon shaped nails Pica – craving non-food (Dirt, Ice, Paper)

Question 9

Iron Deficiency Anemia Treatment

Answer 9

Iron supplementation Monitor erythropoietic activity: An increased retic count is a good thing, Increased HGB, MCH, MCHC, MCV, RDW increases before it gets better

Question 10

Iron Deficiency Anemia CBC

Answer 10

Microcytic, iron deficient RBCs Sometimes resist lysis (show up in the “junk” region) May skew the WBC count (R flag)

Question 11

Anemia from Chronic Disease

Answer 11

Iron deficiency due to infection (Many bacteria are iron dependent and deplete iron stores), Poor erythropoiesis, Chronic inflammation, Malignancy, Severe trauma, Multiple organ failure May cause: BM failure, Decreased EPO production

Question 12

Sideroblastic Anemia

Answer 12

Pathophysiology: Iron is available but it cannot be incorporated into hgb, Abnormal/partial heme synthesis Production of sideroblasts: Abnormal iron containing nRBCs, Iron granules form a ring around the nucleus, Seen in the BM Causes: Hereditary (an enzyme defect), Toxins, Myelodysplastic syndrome (A precursor to acute leukemia)

Question 13

Sideroblastic Anemia Lab Findings

Answer 13

Pappenheimer bodies, Increased RDW, Increased ferritin, Normal or decreased TIBC

Question 14

Thalassemia

Answer 14

A quantitative hgb disorder- One or more of the globin chains in under-produced Two major types: α and β Origin: The Mediterranean Rule of 3 may not work here, High RBC count, low Hgb level, Hct near normal

Question 15

Thalassemia Pathophysiology

Answer 15

Severity depends on specific gene mutation: Anemia, Ineffective erythropoiesis due to poor globin synthesis, BM hyperplasia (Bone deformities) Abnormal erythrocytes: Excessive extravascular hemolysis (Jaundice, Leads to gallstones), Spleen overload (hyposplenism) (Hepatosplenomegaly, Poor secondary lymphoid function, Susceptibility to recurrent infections)

Question 16

Transfusion Dependency- Thalassemia

Answer 16

Development of hemochromatosis: Iron overload from repeated blood transfusions, Iron toxicity (Liver cirrhosis, Heart disease, Diabetes, Endocrine defects)

Question 17

Thalassemia Lab Findings

Answer 17

Anisopoikilocytosis: Microcytic/hypochromic RBCs (RDW is often NORMAL), Teardrop and target cells, nRBCs Inclusions: Howell Jolly bodies, Basophilic stippling Increased bilirubin: Intravascular and extravascular hemolysis, Decreased haptoglobin

Question 18

α-Thalassemia

Answer 18

A group of 4 disorders- Progressively severe 2 α genes are inherited from each parent (4 total) α-Thalassemia develops when 1 or more is deleted, The quantity of production of α-globin chains are increasingly affected Too many β chains are produced and precipitate, damaging the membrane

Question 19

(-α/αα)

Answer 19

Silent carrier, Asymptomatic

Question 20

(–/αα)

Answer 20

α-thalassemia minor, Mild anemia

Question 21

(–/-α)

Answer 21

Hgb H disease, Severe anemia

Question 22

(–/–)

Answer 22

α-thalassemia major, Development of hydrops fetalis, Massive fluid accumulation, Lethal at birth

Question 23

β-Thalassemia

Answer 23

Only 2 β-globin genes Disease is the result of a genetic mutation Reduction in β chain synthesis affects the production of Hgb A as α chains are over produced, precipitate and damage the cell membrane Body compensates by producing non-β hgb’s: Hgb F, Hgb A2 Reduces O2 carrying capacity

Question 24

β-Thalassemia Genetic Combinations

Answer 24

( β+ / β ), (β0 / β) - β-thalassemia minor ( β+ / β+ ), ( β+ / β0), (β0 / β) - β-thalassemia intermedia ( β+ / β+ ), ( β+ / β0), (β0 / β0) - β-thalassemia major

Question 25

β+

Answer 25

a partial block in β chain synthesis

Question 26

β0

Answer 26

a complete absence of β chain synthesis