Anemia and Thalassemia Study Guide- Hematology
| Question | Answer |
| Reticulocyte range | 0.5 - 1.5% |
| Corrected retic count calculation | (Patient Hct)/Normal Hct (45%) X Uncorrected Retic count |
| RDW | Red cell Distribution Width; indication of size (anisocytosis) |
| RDW range | 11.5-13.5% - greater than this indicates anisocytosis |
| Serum Iron range | 50-150micrograms/dL |
| Total Iron Binding Capacity range | 250-450 mcg/dl |
| Transferrin | iron transport protein; transfers in the 2+ state (ferrous) |
| % Saturation range | 20-50% |
| % Saturation calculation | Iron/TIBC X 100 = % |
| Top three procedures to measure iron | 1) serum iron 2) TIBC 3) % Saturation |
| Increased TIBC equals what? | increased transferrin |
| Reasons for decreased serum Iron | IDA; Acute or chronic inflammatory disorders; treatment of other anemias (iron gets used up making more cells); hemorrhage or menstruation |
| Reasons for normal serum iron (in an anemic state) | Thalassemia (Iron levels are critical for determining if this is the cause of anemia) |
| Reasons for increased serum iron | hemachromatosis; acute hepatitis; hemolytic anemias; sideroblastic anemia; thalassemia major |
| Reasons for normal changes in serum iron | 1) age 2) diurnal variation |
| Reasons for increased TIBC | 1) IDA 2) hepatitis |
| Disease states with decreased or normal TIBC | Anemia of chronic disease; hemolytic anemia; chronic liver disease; hemochromatosis; nephrosis |
| Ferritin | Apoferritin (the protein) + iron |
| Ferritin increased in . . . | any condition that leads to increased protein: hepatic necrosis; acute-phase reaction; sideroblastic anemia; hemochromatosis |
| Ferritin decreased in . . . | only in iron deficiency leading to IDA |
| ZPP | zinc protoporphyrin; used as a screening test for lead poisoning; elevated in iron deficient conditions (most porphyrin chelates with zinc ion and makes ZPP) |
| Free Erythrocyte Porphyrin | pretty much the same thing as ZPP, except instead of measuring porphyrin attached to zinc, you extract the free porphyrins from erythrocytes |
| Ferrous iron | 2+ state |
| Ferric iron | 3+ state |
| Iron is eaten mostly as . . . | Ferrous (2+) |
| Iron is bound to apoferritin or transferrin as . . . | Ferric (3+) |
| Infant IDA can result from . . . | Just drinking milk |
| Adult male IDA can result from . . . | GI bleeds |
| Women IDA can result from . . . | Menstruation |
| Patients with gastric resection can have IDA from . . . | impaired absorption |
| First stage of IDA (first of three) | Iron depletion - ferritin is low |
| Second stage of IDA (of three) | Iron-deficient erythropoiesis - increased TIBC |
| Third Stage of IDA (of three) | Full on IDA - microcytic, hypochromic RBCs; increased ZPP and FEP |
| IDA MCV and MCHC | <80 and="" hypochromic="" microcytic=""> |
| IDA serum Fe, TIBC, % saturation | Decreased; increased; decreased (less than 15%) |
| IDA ferritin, ZPP, TfR (transferrin receptor) | decreased, increased, increased (because no iron is being carried, so there are more available transferrin receptors) |
| Anemia of Chronic Disease differences from IDA | can be normocytic/normochromic (or micro/hypo); normal to increased hemosiderin in bone marrow (it's there, just isn't released); normal to decreased TIBC; % saturation is >15% (this is key); normal to increased serum ferritin |
| Anemia of Chronic Disease same as IDA | decreased serum iron |
| Two common causes of macrocytic anemia | Vit B12 deficiency; folic acid deficiency |
| MCV of macrocytic anemia | MCV >99 |
| Vit. B12 aka . . . | cobalamine |
| Needed to absorb Vit. B12 | intrinsic factor |
| Vit B12 absorbed where? | Ileum |
| Common causes of Vit B12 Pernicious anemia | Dietary lack of B12 (not common in U.S.); antibodies against intrinsic factor |
| Features of a macrocytic anemia blood smear | marcrocytic/normochromic RBCs (ovalocytes); hypersegmented neutrophils; |
| Macrocytic bone marrow | hypercellular - M:E of 1:1; (if megaloblastic anemia, shows megaloblastic lagging in nuclei of cells) |
| Macrocytic anemia LD, haptoglobin, and Iron levels | increased (they look yellow); decreased; increased (can't carry iron) |
| Schilling's Test | Drink radioactive B12 and measure what percentage is recovered in the urine in 24hrs; if <5 7="" factor="" intrinsic="" or="" repeat="" than="" with=""> |
| Clinical features of B12 macrocytic anemia | 1) neurological problems 2) smooth tongue 3) yellow appearance |
| Folic acid is absorbed in the . . . | jejunum |
| Folic acid can be stored for ____; B12 can be stored for ___ | weeks; years |
| Sideroblastic anemia aka | iron loading anemia |
| Sideroblastic vs IDA | both are micro/hypo; sideroblastic usually has a dimorphic blood picture and papenheimer bodies; sideroblastic has ringed sideroblasts in bone marrow (stained with Prussian blue); |
| Bone marrow in sideroblastic anemia has . . . | increased hemosiderin; ringed sideroblasts; |
| Sideroblastic serum iron, TIBC, increased % sat, ferritin | increased serum Fe; normal to decreased TIBC; increased %; increased serum ferritin (very important) |
| Hemochromatosis aka | bronze diabetes |
| Basophilic stippling can indicate | lead poisoning; congenital dyserythropoetic anemia; thalassemia alpha and beta (among others) |
| Ham's test aka . . . | Acidified serum test |
| Ham's test tests for what and how does it do it? | Tests for complement mediated hemolysis; Patient serum is mixed with patient RBCs, but without an ABs. If complement is the cause of the hemolysis, it will occur in acidified serum, but not in heated serum (which destroys complement) |
| Ham's test if for which diseases? | Paroxysmal nocturnal hemoglobinuria (PNH); also can be positive for HEMPAS |
| PNH can be tested for with which tests? | Ham's Test; sugar water test |
| What type of hemoglobin causes sickle cell? | HbS |
| What is the amino acid switch that causes sickle cell? | Beta chain, 6th position, Glu --> Val |
| What is the osmotic fragility test for? | Shows the presence of spherocytes; hereditary spherocytosis, and hemolytic anemias are more fragile (also increased in old blood) |
| How is the RBC osmotic fragility test set up? | set up a serial dilution of distilled water and NaCl buffer; first tubes have all 1% NaCl, last tubes have no NaCl; spherocytes will lyse at a higher concentration (in about tube 4) while normally they lyse at about tube 5 or 6 |
| What are some associated signs of hemolytic anemias? | jaundice; dark/red urine; anemia; splenomegaly; hemoglobinuria (this is an important one) |
| What are some examples of intravascular hemolytic anemias? | PNH; MAHA; DIC; Drug reaction in G6PD; transfusion reaction; Hereditary spherocytosis; H. eliptocytosis; H. pyropoikilocytosis; H. stomatocytosis |
| Horizontal defects of RBCs | HE (spectrin form tetramers and protein 4.1 defect) and HPP (alpha spectrin + spectrin dimers) |
| Vertical defects of RBCs | HS (spectrin interaction) |
| Why spherocytes are more easily destroyed? | They aren't as flexible- get caught in spleen where there is too much Na; they run out of energy to pump out excess Na and they are destroyed by macrophages |
| Clinical values of HS hgb, MCV, MCHC) | hgb is decreased; MCV is slightly decreased; MCHC is increased |
| Problems associated with hereditary elliptocytosis | Mostly there are none (90% benign) |
| Describe HPP | Hereditary Pyropoikilocytosis; inherited; horizontal defect; PB shows budding, torn, strange shapes of RBCs |
| Clinical problems associated with HPP | hyperbilirubinemia; anemia |
| Treatment of inherited hemolytic anemias | Often splenectomy is best course; may need exchange transfusions |
| Rh Null disease is associated with . . . | Hereditary stomatocytosis is associated with . . . |
| What is a thalassemia? | A qualitative disorder in one of the chains of hemoglobin |
| What is a hemoglobinopathy? | A quantitative disorder of a hemoglobin chain (too much of one) |
| What is the RBC count, the indices and the typical RBC morphology of thalassemia? | increased RBC (erythroid hyperplasia); micro/hypo; target cells, basophilic stippling |
| What is the cause of siderocytes/sideroblasts? | Sideroblastic anemia; there is a disturbed or missing enzyme in the heme synthesis pathway; this leads to iron accumulation within mitochondria, which eventually rupture and deposit the iron into the cell |
| What causes PA, tropical sprue, and blind loop syndrome? | Malabsorption |
| What does the bone marrow in megaloblastic anemia look like? | hypercellular with an increase in erythroid precursors and a decreased M:E ratio; cells show nuclear lagging (megaloblastic changes) "nuclear-cytoplasmic asyncrhony" - metamyelocytes and bands with loose chromatin; increased intercellular destruction |
| % saturation of iron in IDA vs. anemia of chronic disease | IDA is <15 chronic="" disease="">%15 |
| What does a long-term hookworm infection do to the blood? | causes anemia - looks like IDA (micro/hypo, elliptocytes); also increased eosinophils |
| What is myelophthisic anemia? | destruction of blood precursor cells and tissues caused by invasion from an non-hematopoetic cell like (like a tumor or cancer); dacryocytes and bizzare platelets are common (like MMM, which is also fibrotic) |
| What does the blood smear of a burn victim look like? | budding, fracturing of RBCs (looks like Herditary Pyropoikilocytosis) |
| What does the bone marrow of IDA look like? | decreased M:E ratio, increased cellularity |
| What does the bone marrow of pernicious anemia look like? | decreased M:E ratio; increased cellularity; macrocytic changes (lagging nucleus) |
| What does the bone marrow of hereditary elliptocytosis look like? | some increased cellularity (enough to compensate the benign condition of HE) |
| What condition causes increased Heinz bodies? | Glucose 6 Phosphate deficiency (G6PD) |
| What are Heinz bodies made of? | denatured hemoglobin |
| What is basophilic stippling composed of? | RNA and ribosomes |
| What does Prussian blue stain? | Iron deposits |
| What is anemia in sickle cell caused by? | extravascular hemolysis (cells taken out by spleen) |
| What are some complications caused by sickle cell anemia? | sickled cells stick in narrow capillaries and can cause a vaso-oclusive crisis |
| What causes a vaso-oclusive crisis? | sickle cells |
| What happens to the blood in chronic renal failure? | a toxic environment (from increased BUN) and that leads to the formation of ecchinocytes |
| What happens to the blood in alcoholism? | can cause stomatocytes and/or ecchinocytes |
| What happens to the blood in chronic liver disease? | typically causes macrocytic anemia; can cause codocytes and/or ecchinocytes |
| What are four states that can lead to target cells? | thalassemia; liver disease; hemoglobin C disorders; splenectomy |
| What drugs and chemicals can cause aplastic anemia? | drug - chloramphenicol (and sulfa and penicillin);chemcial - benzene (and arsenic and insecticides) |
| Congenital red cell aplasia is called . . . | Diamond Blackfan |
| Congenital aplastic anemia is called . . . | Fanconi's anemia |
| What does bone marrow in aplastic anemia look like? | <25 cells="">70% fat |
| What drugs can cause hemolysis of blood cells? | penicillin, quinidine, aldomet, |
| What is the hemolytic mechanism of penicillin | drug adsorption to the membrane (which then activates IgG and complement) |
| What is the hemolytic mechanism of aldomet? | unknown, but it causes Abs to attack RBCs |
| What is G6PD? | glucose 6 phosphate dehydrogenase deficiencty; the most common erythorcyte enzyme disorder |
| Why is G6PD deficiency toxic to cells? | helps reduce oxidized glutathione; when it can't the cells burst due to oxidative stress |
| What are some drugs that increase the hemolytic activity in G6PD deficiency? | antimalrials (primaquine, pamaquine) |
| Hemolytic uremia syndrome can cause what complication? | acute or chronic renal failure |
| How is HUS caused? | bacterial infection releases toxins into blood stream; toxins cause release of PLTs which attach to glomeruli and tear up passing RBCs |
| Which age group is most affected by HUS? | children |
| Which age group is most affected by TTP? | adults |
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