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Flashcards in RBC/WBC Deck (86):
1

2

Where is EPO made?

Interstitial Fibroblast Cells of the Kidney near peritubular capillaries

3

Hypoxia shifts the O2 dissociation curve

LEFT

4

Anemia shifts the O2 dissociation curve

LEFT

5

Polycythemia vera has what effect on EPO production? O2 binding curve?

Decreases EPO due to high oxygen environment; Shifts O2 curve Right

6

Altitude has what effect on EPO production?

Increases it

7

Low O2 conditions will cause a _________ in EPO production and shift the O2 curve ______

INCREASE; LEFT

8

What 2 types of cancer may result in EPO production?

Renal Cell Carcinoma and to a lesser extent HCC

9

Clinical Features of Iron Deficiency Anemia

Microcytic Anemia, Koilonychia, Pica

10

Koilonychia

spoon-shaped finger-nails

11

Polycythemia vera is characterized by

bone marrow disease that results in an abnormal increased # of RBCs

12

Normal Reticulocyte count is

1-3%

13

High Reticulocyte count is

~10% "Reticulocytosis"

14

Koilonychia is pathognomonic of

Iron deficient Anemia

15

4 Types of Microcytic Anemia

Iron deficiency, Anemia of Chronic Disease, Sideroblastic, and Thalassemia

16

Microcytic Anemia is a MCV value of

17

The following are features of iron deficiency anemia: _________ Serum Ferritin _________ TIBC _________ Serum Iron _________ % Saturation _________ FEP

1. Decreased serum ferritin (stored Fe)

18

Reticulocyte counts should be corrected for

ANEMIA

19

Corrected Reticulocyte Count Equation =

HCT/45 X reticulocyte count (45=normal HCT)

20

1st Sign of increased EPO

Reticulocyte response/release from BM

21

How long before immature reticulocytes become mature?

~24hrs

22

An inadequate reticulocyte response implies the marrow is

not working well, dysplastic, or aplastic

23

The following are features of Anemia of Chronic Disease: _________ Serum Ferritin _________ TIBC _________ Serum Iron _________ % Saturation _________ FEP

Increased Serum Ferritin > 30 Decreased TIBC Decreased Serum Iron Decreased % Saturation

24

The following are features of Sideroblastic Anemia: _________ Serum Ferritin _________ TIBC _________ Serum Iron _________ % Saturation

Increased Serum Ferritin Decreased TIBC Increased Serum Iron Increased % Saturation

25

The following are features of Thalassemia: _________ Serum Ferritin _________ TIBC _________ Serum Iron _________ % Saturation

Increased Serum Ferritin Decreased TIBC Increased Serum Iron Increased % Saturation

26

Prussian Blue Stain is used to stain ______; It is diagnostic for __________ type of Anemia

Iron; Sideroblastic Anemia - Ringed Sideroblasts

27

Causes of Iron Deficient Anemia

Malnutrition, Malabsorption (Crohn's), Blood Loss (PUD, carcinoma, hookworms), Pregnancy, Menorrhagia, Gastrectomy

28

4 Stages of Iron Deficient Anemia

1. Iron Stores Depleted 2. Serum Iron Depleted 3. Normocytic Anemia 4. Microcytic Anemia

29

TIBC is a measure of

Transferrin in blood

30

% Saturation is a measure of

% of Iron-bound Transferrin molecules in blood

31

Serum Ferritin is a measure of

stored iron w/in bone marrow macrophages and liver

32

Treatment for Iron Deficient Anemia

Ferrous Sulfate, Address any underlying conditions

33

What is PLUMMER-VINSON SYNDROME?

a condition characterized by Iron Deficient Anemia + Esophageal webbing + Atrophic glossitis (anemia, dysphagia, beefy-red tongue)

34

Describe the mechanism involved in Anemia of Chronic Disease

Chronic Disease/Cancer -> chronic inflammation -> acute phase reactants - Hepcidin

35

What is Hepcidin's role?

sequesters Iron into BM macrophages and histiocytes of liver and prevents its transport out; also suppresses EPO (thought to help eliminate a bacterial infection)

36

Stages of Anemia of Chronic Disease

Begins as Normocytic Anemia and progresses to Microcytic Anemia

37

Treatment for Anemia of Chronic Disease

Address underlying cause of inflammation; Exogenous EPO for subset of cancer patients

38

Describe the mechanism involved in Sideroblastic Anemia

Decreased protoporphyrin synthesis -> reduced heme production -> reduced Hb

39

Describe the rate-limiting step of protoporphyrin synthesis

1st step: converts Succinyl-CoA to Aminolevulinic Acid (ALA); catalyzed by ALA synthase + required Cofactor Vitamin B6

40

ALA is converted to ____________ by __________

porphobilinogen by ALA Dehydrogenase

41

Final Step in protoporphyrin synthesis

Ferrochelatase links protoporphyrin and Iron to form HEME

42

Final Step in protoporphyrin synthesis occurs

erythroid precursor MITOCHONDRIA (surrounding nucleus)

43

What else is occurring during protoporphyrin synthesis

Iron transport to erythroid precursor MITOCHONDRIA

44

In Sideroblastic anemia where there is decreased protoporphyrin synthesis, what occurs in the erythroid precursor cell?

Iron accumulates in the mitochondria creating an iron-laden ring around the nucleus --> eventually the toxic effects of iron cause cell death and Iron leaks into marrow (taken up by macrophages) and blood

45

The Iron-laden ring around the nucleus of erythroid precursors are characteristic of __________ cells

Ringed Sideroblasts

46

The most common congenital cause of Sideroblastic anemia is:

ALA S enzyme defect

47

Common causes of acquired Sideroblastic anemia are:

Alcoholism, Lead Poisoning, Vitamin B6 deficiency

48

How can Alcoholism lead to Sideroblastic anemia?

Direct Mitochondrial Poison

49

How can Lead Poisoning lead to Sideroblastic anemia?

Denatures the enzymes: ALA D and Ferrochelatase

50

How can Vitamin B6 deficiency lead to Sideroblastic anemia?

Necessary Cofactor for ALA S, inhibits the RATE-LIMITING Step of protoporphyrin synthesis

51

What Drug Therapy has been linked to Sideroblastic anemia due to its effect on Vitamin B6 depletion?

Isoniazid for TB Tx

52

Describe the mechanism involved in Thalassemia

Decreased production of globin chains

53

Anemia of Chronic Disease is common, occurring in ____% of Microcytic anemias

30%; usually accompanied by little to no morphological changes on peripheral smear

54

Anemia of Chronic Disease lasts

longer than 1-2 months

55

Causes of Anemia of Chronic Disease

Infection, Non-infectious inflammation, Malignancy

56

Hepcidin sequesters Iron and ALSO

suppresses EPO

57

In 25% of cases, the only chronic diseases present in a patient w/ Anemia of Chronic Disease

Diseases such as: congestive heart failure and diabetes mellitus

58

In Anemia of Chronic Disease, anemia is usually

mild-moderate w/ HCT > 25; mainly due to EPO repression by Hepcidin

59

CBC includes:

Hb, HCT, WBC count, Platelet count, RBC count Calculate: MCV, MCH, RDW (NOT LAP)

60

Hemoglobin F shifts the O2 binding curve

LEFT - driving EPO production and Hb synthesis

61

Most common anemia in babies?

Iron deficiency since breast milk lacks Iron

62

HbF tetramer is composed of

2-alpha and 2-gamma

63

Extramedullary Hematopoiesis occurs where in fetuses and premature infants

yolk sac -> liver -> BM

64

What anemic condition results in Extramedullary Hematopoiesis in liver, spleen, face, and skull?

Beta-thalassemia Major

65

HbF is replaced by _____ ~ ____%

HbA ~97%; HbF may persist at ~1%

66

HbA2 may present at ~____%

~3%

67

HbF is broken down in the months following birth by

Splenic histiocytes thus “physiologic jaundice”

68

Explain how HbF/Fetal RBC breakdown may result in "physiologic jaundice"

RBC/HbF is broken down by splenic histiocytes. Hb is broken into heme (Fe and protoporphyrin) and globin. Protoporphyrin is then broken down into bilirubin, unconjugated bilirubin is fat-soluble (+serum albumin), enters the blood & is delivered to the liver for conjugation. If the concentration of unconjugated bilirubin exceeds the liver's ability to conjugate --> a build up of unconjugated bilirubin in blood results in "physiologic anemia"

69

Reticulocyte response to anemia would result in a CRC of > ___%

> 3%

70

In anemia, a CRC

dysplastic or aplastic BM or failure to produce EPO

71

How can alcohol lead to macrocytic anemia?

DIRECT toxic effects causing macrocytic anemia

72

Haptoglobins function

binds free Hb in blood and returns it to to the liver (saves a small amount of Hb)

73

Hemosiderinuria

Hb taken up by renal tubular cells, destroys Hb and binds as Hemosiderin in cell. Sloughing of renal tubular cells results in Hemosiderinuria

74

Hemosiderinuria is a common lab finding in

Intravascular Hemolytic Normocytic Anemia - PNH, G6PD def.,

75

HbA tetramer is composed of

alpha2, beta2 (97%)

76

HbA2 tetramer is composed of

alpha2, delta2 (~3%)

77

Children usually have lower Hb levels because they typically have higher _______ and ______

Phosphorus levels and 2,3-BPG

78

2,3-BPG shifts the O2 dissociation curve to the

RIGHT

79

Parvovirus B19 infects

erythroid precursors

80

Risk of aplastic crisis from a Parvovirus B19 infection occurs in

beta-thalassemia Major, Hereditary Spherocytosis, Sickle Cell Anemia

81

Howell-Jolly bodies

DNA fragments in RBCs - indicative of splenic dysfunction

82

What condition is likely to have Howell-Jolly bodies appear following Treatment?

Hereditary Spherocytosis

83

The mechanism of Hereditary Spherocytosis is

defective RBC cytoskeletal proteins resulting in cell shape changes (biconcave to sphere) and membrane blebs that are cleaved by splenic histiocytes

84

Which hormone drives EPO production?

Testosterone

85

In what condition would you see a large number of nucleated RBCs?

beta-thalassemia Major - due to extra medullary erythropoiesis

86

What inherited genetic mutations may be selected for by their ability to protect against Plasmodium falciparum Malaria ?

Sickle Cell Anemia, Thalassemia, G6PD deficiency