The Anemias And Polycythemias Part 2

Front 1

Etiology of Hereditary Spherocytosis

Back 1

Inherited. Usually autosomal dominant.

Front 2

Most common anemia of Caucasians

Back 2

Hereditary spherocytosis.

Front 3

What membrane proteins are deficient in hereditary spherocytosis?

Back 3

Spectrin and ankyrin.

Front 4

Cause of hereditary spherocytosis

Back 4

Defect in RBC membrane; cells become hyperpermeable to sodium; water enters cells until the cell eventually ruptures.

Front 5

What test is increased with hereditary spherocytosis?

Back 5

Osmotic fragility test.

Front 6

Other causes of hereditary spherocytosis

Back 6

Autoimmune hemolytic anemia, thermal damage, and normal senescene of RBCs (normal aging and dying).

Front 7

Cholelithiasis

Back 7

Extra bilirubin produced from breakdown of cells, gall stones. Perform splenectomy.

Front 8

How does severity of HS differ?

Back 8

Differs among families and even patients within the same family.

Front 9

25% of patients with HS have:

Back 9

Compensated hemolytic disease, no anemia, slight splenomegaly.

Front 10

What do most patients with HS develop?

Back 10

Compensated hemolytic disease.

Front 11

HS can be fatal for patients who are:

Back 11

Homozygous for the disease.

Front 12

What do untreated older patients with HS typically develop?

Back 12

Pigment bile stones from excess bilirubin.

Front 13

Osmotic fragility test

Back 13

Patient's RBCs are subjected to varying salt solutions ranging from isotonic to distilled water. Each tube is observed for the start of hemolysis and complete hemolysis. Complete hemolysis is reported on the patient's sample.

Front 14

Lab findings in HS

Back 14

Hemoglobin can be normal or decreased, retic count usually greater than 8%, and spherocytes are the only cells with increased MCHC.

Front 15

Etiology of hereditary elliptocytosis

Back 15

Inherited usually autosomal dominant. Defect of spectrin which leads to membrane instability. Also abnormally permeable to sodium.

Front 16

Clinical signs of HE

Back 16

Most individuals display no clinical symptoms.

Front 17

Clinical findings of HE

Back 17

RBC survival time can be decreased but most patients compensate well. Elliptocytes generally make up more than 25% of RBCs and sometimes more than 60. Patients often respond well to splenectomy.

Front 18

Another name for overhydrated stomatocytosis

Back 18

Hydrocytosis.

Front 19

Another name for dehydrated stomatocytosis

Back 19

Xeroxytosis.

Front 20

Cell morphology of overhydrated stomatocytosis and dehydrated stomatocytosis

Back 20

Stomatocytosis = stomatocytes

Xeroxytosis = Crenated cells, blister cells, and target cells.

Front 21

Etiology of overhydrated stomatocytosis and dehydrated stomatocytosis

Back 21

Inherited: autosomal dominant; exact defect unknown. Both are due to alterations in the permeability of the RBC membrane to cations (Sodium and potassium) in hydrocytosis, the cell gains too many sodium ions and therefore water. In xeroxytosis, the cell loses more potassium ions than sodium and loses water.

Front 22

Glucose 6 phosphate dehydrogenase deficiency etiology

Back 22

Inherited. Sex linked disorder seen in 10-15% of American black males. Homozygous females may also develop this disorder.

Front 23

Deficiency of glucose 6 phosphate dehydrogenase enzyme

Back 23

Leads to hemolysis only when the patient is exposed to redox compounds (antimalarial drugs) infections or during the newborn period.

Front 24

What may follow a hemolytic episode? (Glucose 6 phosphate dehydrogenase deficiency)

Back 24

Hemoglobinuria and jaundice.

Front 25

What does oxidative desaturation of hemoglobin lead to? What stain is used to visualize inclusions?

Back 25

Formation of methemoglobin which precipitates as Heinz bodies in RBCs. Crystal violet.

Front 26

3rd most prevalent hemoglobin variant in the world

Back 26

Hemoglobin C disease.

Front 27

Cell morphology of hemoglobin C

Back 27

Normochromic/normocytic, hemoglobin c crystals, target cells.

Front 28

Etiology of hemoglobin c

Back 28

Inherited (hemoglobinopathy). Due to an amino acid substitution of lysine for glutamic acid on the 6th position of the beta chain. Found primarily in blacks.

Front 29

What do the hgb c bars block? Where do they melt?

Back 29

Block the micro vascular system, but melt in the micro environment of the spleen.

Front 30

What is the RBC lifespan reduced to with hemoglobin c?

Back 30

30-55 days.

Front 31

Clinical and lab findings of hemoglobin c disease

Back 31

Usually asymptomatic, occasional joint and abdominal pain. Splenomegaly, hgb 8-12, hct 25-35, see hgb c crystals, target cells, and folded cells on smear.

Front 32

Hematological findings of hemoglobin sc disease

Back 32

Target cells, hemoglobin sc crystals.

Front 33

Etiology of hemoglobin sc disease

Back 33

Inherited (hemoglobinopathy). Found primarily in blacks, less severe than hgb ss disease, but more severe than hgb cc disease.

Front 34

What contributes to the pathophysiology of hgb sc disease? What can patients develop?

Back 34

Sickling and crystal formation can develop vaso-occlusive crises.

Front 35

Hgb and hct level of patients with hemoglobin sc

Back 35

Hgb 10-14, hct above 25%.

Front 36

Morphology of sickle cell anemia

Back 36

Sickle cells, target cells, NRBCs.

Front 37

Etiology of sickle cell anemia

Back 37

Inherited (hemoglobinopathy) due to an amino acid substitution of valine for glutamic acid found at the seventh position. Primarily in blacks.

Front 38

1. Homozygous hemoglobin SS = ____________

2. Heterozygous hemoglobin SA = ____________

Back 38

1. Sickle cell anemia

2. Sickle cell trait

Front 39

When do the first signs of sickle cell anemia usually appear?

Back 39

6 months of age.

Front 40

Clinical symptoms of sickle cell anemia

Back 40

Moderate to severe anemia, cholelithiasis, cholecystitis, cardiac overload, cardiac hypertrophy, CHF, leg ulcers, cardiac enlargement, joint and skeletal problems, and renal complications.

Front 41

Causes of sickling

Back 41

Oxygen deprivation, ph changes, dehydration, infections, fever, exposure to extreme cold, and emotional stress.

Front 42

Aplastic crisis

Back 42

Associated with infections; becomes overworked and eventually a temporary marrow aplasia develops.

Front 43

Hemolytic crisis

Back 43

Acute exacerbation of the anemia. H & H both decrease. Patient may become jaundiced. Autosplenectomy. (Gets multiple infarcts)

Front 44

Vaso-occlusive (painful) crisis

Back 44

Hallmark clinical sign of sickle cell anemia; severe pain, tissue damage including necrosis, precipitated by infections, fever, acidosis.

Front 45

Hematological findings of sickle cell anemia

Back 45

Normocytic/normochromic. Sickle cells, target cells, retic count 10-20%, hgb of 6-10 and hct 18-30.

Front 46

Diagnostic tests for sickle cell anemia

Back 46

Hemoglobin solubility test: screening test. Utilizes sodium metabisulfite.

Hemoglobin electrophoresis: definitive test.

Oxygen deprivation test.

Front 47

Therapy for sickle cell anemia

Back 47

Rehydration, antibiotics when indicated (bacteria can cause crisis), pain meds, transfusions, hydroxurea to increase hgb F, and bone marrow transplant.

Front 48

Second most prevalent hemoglobinopathy in the world

Back 48

Hemoglobin E. 50% of those in Thailand, 15-30% of Asian immigrants, and also found in blacks.

Front 49

What does hemoglobin E form as a result of?

Back 49

Forms as result of lysine for glutamic acid in the beta chains.

Front 50

Those that are homozygous for Hgb E

Back 50

Have a mild microcytic/hypochromic anemia with cl decreased RBC survival time. Hgb E trait doesn't demonstrate any disease.

Front 51

Another name for the thalassemias

Back 51

Cooley's anemia.

Front 52

Morphological classification of the Thalessemias

Back 52

Microcytic hypochromic.

Front 53

What is thalassemia caused by?

Back 53

Variant or missing genes. Almost 400 unique mutations.

Front 54

Alpha thalassemia

Back 54

Four genes are involved in making the globin part of hemoglobin, two from each parent. Occurs when one or more of these genes is variant or missing.

Front 55

People with only one gene are called _____________________ and have no signs of illness.

Back 55

Silent carriers.

Front 56

People with two genes affected are called ________________.

Back 56

Alpha thalassemia trait or alpha thalassemia minor. Have mild anemia and are considered carriers.

Front 57

People with 3 genes affected (thalassemia)

Back 57

Have a moderate to severe anemia or hemoglobin H disease.

Front 58

Babies with all 4 genes affected (thalassemia)

Back 58

Aka alpha thalassemia major or hydrops fetalis. Usually die before or shortly after birth.

Front 59

Beta thalassemia

Back 59

Two genes are involved in making the beta globin part of hemoglobin, one from each parent. Occurs when one or both of the two genes are variant.

Front 60

If one gene is affected, a person is a ____________ and has _____________. What is this condition called? (Beta thalassemia)

Back 60

Carrier, mild anemia. Called beta thalassemia trait or beta thalassemia minor.

Front 61

If both genes are variant, a person may have _____________ or ______________________. (Beta thalassemia)

Back 61

Moderate anemia (beta thalassemia intermedia or mild Cooley's anemia) or severe anemia (beta thalassemia major or Cooley's anemia).

Front 62

Another name for beta thalassemia major

Back 62

Cooley's anemia. Rare condition.

Front 63

What is a variant of beta thalassemia?

Back 63

Hereditary persistence of fetal hemoglobin.

Front 64

HDN

Back 64

Immune hemolytic disorder in which the RBCs of the fetus are destroyed by the maternal IgG antibodies. Usually maternal antibodies provide the fetus with immune protection because the fetus is unable to synthesize adequate immunoglobulin.

Front 65

How can a mother be sensitized? (HDN)

Back 65

Through previous pregnancy or blood transfusions.

Front 66

IgG that crosses placenta

Back 66

Can combine with the antigens on fetal RBCs resulting in destruction of fetal cells.

Front 67

4 conditions that must be met for HDN to occur

Back 67

1. Mother is exposed (sensitized) to an RBC antigen she lacks.

2. Fetus must possess the antigen to which the mother is sensitized.

3. Mother must produce antibodies to the foreign antigen.

4. Mother's antibody must be able to cross the placenta and enter the fetal circulation.

Front 68

What are most cases of HDN due to?

Back 68

Rh or ABO incompatibilities. ABO more common and milder than Rh incompatibilities.

Front 69

ABO incompatibilities are usually due to:

Back 69

Mother being type O and baby being born A, B, or AB.

Front 70

Rh incompatibilities are due to:

Back 70

Rh negative mother and delivering a positive set. Rate because of the use of Rh immune globulin.

Front 71

Frequency of ABO, Rh, and other (Duffy, Kell) HDN

Back 71

Abo: 65%

Rh: 33%

Other: 2%

Front 72

What group of people is paroxysmal cold hemoglobiniria found in historically? What group of patients is it found in now?

Back 72

Adults with congenital or tertiary syphilis. Children with viral diseases such as chicken pox, measles, mumps, and IM or bacterial infections with haemophilus influenzae or klebsiella pneumoniae.

Front 73

What type of disorder is paroxysmal cold hemoglobinuria?

Back 73

Transient. Manifests 3 days to 5 weeks after infection and after exposure to cold. Hemoglobinuria is one sign of the disease.

Front 74

Screening test for paroxysmal cold hemoglobinuria

Back 74

Donath landsteiner screening test.

Front 75

Interpretation of donath Landsteiner screening test

Back 75

Should be no hemolysis in control tube. If there is, it's inconclusive. Positive = hemolysis. Negative = no hemolysis.

Front 76

Paroxysmal Noctural Hemoglobinuria

Back 76

Acquired by hemolytic anemia of unknown etiology. RBCs have a membrane defect that makes them abnormally sensitive to lysis by complement.

Front 77

Classic symptom of PNH

Back 77

Hemoglobin in urine following sleep occurs most often in middle aged persons of either gender.

Front 78

What can PNH develop from or into?

Back 78

Aplastic anemia. 25%.

Front 79

Diagnostic tests for PNH

Back 79

Sugar water test (screening)

Acid serum/Hams test (confirmatory)

Flow cytometry

Front 80

What is polycythemia relative to?

Back 80

How much fluid is in the body.

Front 81

Relative polycythemia

Back 81

Due to a decrease in the plasma volume.

Front 82

Absolute polycythemia

Back 82

Primary: (polycythemia vera) etiology unknown.

Secondary: due to decrease of erythropoietin.

Front 83

Best diagnostic test for PNH

Back 83

Flow cytometry: counts cells and identifies them.

Front 84

5-10% of PNH patients develop:

Back 84

Myelogenous leukemia.

Front 85

What is relative polycythemia caused by?

Back 85

A relative decrease of the plasma. Number of cells not increased, only fluid volume is decreased.

Front 86

Relative polycythemia may be found in patients with:

Back 86

Acute dehydration, smokers, cardiovascular problems, hypertension, and patients on diuretic therapy.

Front 87

Absolute polycythemia: Primary polycythemia: cause and what is seen on smear?

Back 87

Aka polycythemia rubra vera. Myeloproliferative disorder causing all cells to be increased, especially RBCs. Cause is unknown and usually occurs in patients over 60. Slight male predominance. NRBCs may be seen on smear.

Front 88

Absolute polycythemia: secondary polycythemia

Back 88

Caused by an increase level of erythropoietin. Increased level may be seen in patients living in high altitudes, patients with COPD, CHF, and smokers.

Front 89

Treatment of polycythemia

Back 89

Regular phlebotomies. Important to stay hydrated.