Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

gen-path 2 > RBC disorders > Flashcards

RBC disorders Flashcards

1
Q

what are the 3 general categories of anemia?

A

1) RBC (blood) loss
2) Decreased RBC Survival
3) Decreased RBC Production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Young healthy subjects can tolerate rapid loss of _________ with few symptoms

A

500-1000 mL

up to 15-20% of total blood volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the symptoms of a blood loss of 1500-2000mL?

A
  • all patients are symptomatic
  • thirst
  • shortness of breath
  • loss of consciousness
  • sweating
  • rapid pulse, decreased blood pressure
  • clammy skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Rapid loss of _______ mL produces shock

A

2000-2500

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is anemia?

A
  • Chronic blood loss

- when the rate of loss exceeds the capacity for RBC regeneration or when iron reserves are depleted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

________________ due to ulcer or neoplasm, or ______________ are important causes of iron deficiency

A

1) Chronic GI hemorrhage

2) GYN hemorrhage (menorrhagia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Hemolytic anemias are characterized by what?

A

shortened red cell survival and retention of products of red cell destruction (iron)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is Intravascular hemolysis?

give examples:

A
  • destruction of RBC within the circulation
  • mechanical trauma (e.g., from a defective heart valve)
  • hemolytic transfusion reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what causes hemoglobinemia?

A

Hemoglobin released from RBC into circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Hemoglobin released from RBC into circulation is bound to ____________, a binding protein, and cleared from the circulation by the liver.

A

haptoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

A decrease in serum _____________ is a key feature of intravascular hemolysis

A

haptoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what happens when plasma hemoglobin levels exceed amount of available haptoglobin?

A

free hemoglobin is excreted in the urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the term for excreting free hemoglobin in the urine?

A

hemoglobinuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

iron that accumulates in __________ cells in the kidney as a breakdown product of hemoglobin is lost in the urine when these cells are shed

A

proximal tubular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is hemosiderinuria?

A
  • brown urine

- when proximal tubular cells of kidney die off and release iron from excreted hemoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Conversion of heme (derived from hemoglobin) to bilirubin leads to what 2 conditions?

A

hyperbilirubinemia and jaundice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The degree of jaundice during intravascular hemolysis is dependent on what?

A

the functional capacity of the liver and rate of hemolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

T/F: Levels of haptoglobin in cases of intravascular hemolysis are characteristically high

A

FALSE

they are low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is extravascular hemolysis?

A

destruction of RBC in reticuloendothelial system (spleen, liver)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are some examples of extravascular hemolysis

A

Hereditary spherocytosis

sickle cell anemia

erythroblastosis fetalis (antibody-mediated hemolytic disease of the newborn)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Damaged or abnormal RBC are removed in the _____, where hemoglobin is broken down intracellularly

A

spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what happens to free hemoglobin during extravascular hemolysis?

A

hemoglobin breakdown products are increased (hyperbilirubinemia) and jaundice may result

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Chronically elevated levels of bilirubin can promote formation of _________

A

gallstones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what 2 groups are hemolytic anemias classified into?

A

classified by the mechanism of red cell destruction

  • intrinsic defects (hemoglobin production, membrane abnormality)
  • extrinsic defects (antibody, mechanical trauma)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

which types of hemolytic anemias are usually inherited? which are caused by acquired abnormalities?

A

intrinsic = inherited

extrinsic = acquired

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are the 4 Intrinsic Defects that cause hemolytic anemia?

A

1) membrane defects
2) Abnormal hemoglobin
3) lack of globin chains
4) metabolic defects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

______________ is an intrinsic, extravascular hemolysis

A

hereditary spherocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is hereditary spherocytosis?

A
  • An inherited defect in the red cell membrane

- results in less deformability of RBC, so that they are sequestered and destroyed in the spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The specific defect of hereditary spherocytosis can be a qualitative or quantitative deficiency of ______, a structural protein of the cytoskeleton

A

spectrin

  • this means that the severity of the disease is variable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

in what pattern is hereditary spherocytosis inherited? At what age does it show?

A
  • Autosomal dominant inheritance in most cases

- Manifest in adult life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what are the pros/cons to removing the spleen in a patient with hereditary spherocytosis?

A
  • Removal of spleen results in normal red cell survival
  • but not normal red cell morphology
  • after surgery, production of spherocytes continues, but they do less damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

this disease is caused by abnormal hemoglobin, and leads to extravascular hemolysis:

A

sickle cell anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is sickle cell anemia?

A
  • An inherited defect (autosomal codominant) in the structure of globin chain
  • causes hemoglobin to gel upon deoxygenation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

The specific defect of SSA is a single base pair substitution in DNA that causes a single amino acid substitution of ___________ for _________

A

valine for glutamic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

in sickle cell anemia, where on the protein does the single base pair substitution take place?

A

at position 6 in the beta chain of globin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Under what conditions will the abnormal hemoglobin of SSA polymerizes, causing the RBC to assume a “sickle” shape.

A

low oxygen conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what are the characteristics of “sickle” shaped RBC’s? what problems can they cause?

A
  • cells are rigid and vulnerable to splenic sequestration (decreased survival)
  • can also block the microcirculation causing ischemia and/or infarction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Sickle cell disease occurs in homozygotes for ____

A

HbS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what are the clinical characteristics of sickle cell anemia?

A
  • severe anemia

- vaso-occlusive crises, including acute chest syndrome and stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

name the complications associated with SSA?

A

autosplenectomy
painful crises
leg ulcers
retinal and renal thromboses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

About __% of blacks in USA have sickle cell trait.

why are most people with the genetic abnormality asymptomatic?

A

8%

  • essentially asymptomatic because less than half of the hemoglobin is abnormal and the concentration of HbS within the RBC is insufficient to cause sickling
42
Q

what condition causes extravascular hemolysis due to Lack of globin chains?

A

thalassemia

43
Q

what is thalassemia?

A
  • An inherited defect (autosomal codominant)

- results in diminished or absent synthesis of either the alpha or beta globin chains of hemoglobin

44
Q

what types of genetic mutations cause thalassemia?

A

1) whole or partial gene deletion
2) mutations in the coding sequence or promotor region
3) mRNA instability

45
Q

The type of thalassemia is named for the ___________ produced in reduced amounts

A

globin chain

46
Q

what is the result of decreased globin chain production during thalassemia?

A

results in:
- decreased hemoglobin production

  • anemia is the principal clinical manifestation
47
Q

why does thalassemia cause RBC membrane damage and premature destruction of RBC precursors in the marrow and spleen?

A

due to precipitation of the relative excess of the other globin chain within RBC

(the 2 effects are also called ineffective erythropoiesis and extravascular hemolysis)

48
Q

what are the clinical manifestations of thalassemia?

A

vary from:
- severe transfusion-dependent anemia and iron overload (thalassemia major)

to

  • mild anemia (thalassemia minor)
49
Q

In almost all cases of thalassemia, there is a moderate to marked __________ with target cells and ___________ stippling of the red cells present on the blood smear

A

microcytosis (low MCV)

basophilic stippling

50
Q

in what groups is thalassemia common?

A

persons of Mediterranean, African, and Southeast Asian descent

*reduces effects of milaria

51
Q

Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is an example of a _________ defect that causes extravascular hemolysis

A

metabolic defect

52
Q

how is G6PD inherited? what groups are more likely to have it?

A

An inherited defect (X-linked) encountered primarily in blacks

53
Q

what are the pathological characteristics of a G6PD deficiency?

A

red cells are susceptible to oxidant injury by drugs or toxins (antimalarials, sulfonamides, etc.)

54
Q

in G6PD deficiency, The denaturation of ______________________ causes it to precipitate within the cell and attach to the RBC membrane

A

oxidized hemoglobin

55
Q

what are the effects on the RBC’s with a G6PD deficiency? when is the condition symptomatic or asymptomatic?

A

The RBC membrane’s flexibility is reduced, leading to extravascular hemolysis

The condition is asymptomatic in the absence of the oxidant.

56
Q

what are the 3 types of extrinsic defects that cause hemolytic anemia?

A

1) Immune destruction
2) Mechanical trauma
3) Infections

57
Q

“Bite” cells are the morphologic hallmark for ______________ (a condition) on cytologic exam

A

G6PD deficiency

58
Q

what are the 3 types of autoimmune (immune destruction) conditions that cause hemolytic anemia

A

1) Hemolytic disease of the newborn (erythroblastosis fetalis, immune hydrops)
2) Hemolytic transfusion reaction
3) Autoimmune hemolysis

59
Q

what causes Erythroblastosis fetalis (AKA “Hemolytic disease of newborn”)

A

caused by blood group incompatibility between the mother and fetus

60
Q

during Erythroblastosis fetalis, the mother’s immune system makes ____________ that cross the placenta and attach to the fetal RBC, resulting in extravascular hemolysis

A

antibodies (IgG)

61
Q

_____ and _____ antigens (especially anti-D) are most important in the erythroblastosis fetalis disorder

A

ABO and Rh antigens (especially anti-D)

62
Q

to prevent hemolytic disease of newborns, Rh-negative mothers are given __________ within 72 hours of delivery of an Rh-positive fetus

A

anti-D (Rhogam)

63
Q

anti-D binds to the _________ fetal cells and removes them from the maternal circulation before the mother can generate an antibody response and become sensitized

A

Rh-positive

64
Q

______________ disease occurs in group A and B infants born to group O mothers

A

ABO hemolytic

65
Q

what are the characteristics of Hemolytic transfusion reactions?

A
  • intravascular hemolysis
  • transfusion of incompatible red cells into a sensitized patient results in binding of antibody (in patient) to antigen (transfused RBC)
66
Q

what are the effects of hemolytic transfusion reactions?

A

Activation of coagulation cascade with bleeding, renal failure, shock, and death can occur

67
Q

what are the general characteristics of Autoimmune hemolysis ?

A
  • extravascular hemolysis

- Patient makes antibodies to his/her own RBCs

68
Q

what can happen during autoimmune hemolysis when antigen binds to RBC’s?

A
  • Antibody-coated cells can be lysed (complement activation)
    or
    removed by the reticuloendothelial system
  • Phagocytosis of antibody-coated RBC can lead to partial loss of red cell membrane (spherocytes).
69
Q

what causes Erythroblastosis fetalis (AKA “Hemolytic disease of newborn”)

A

caused by blood group incompatibility between the mother and fetus

70
Q

during Erythroblastosis fetalis, the mother’s immune system makes ____________ that cross the placenta and attach to the fetal RBC, resulting in extravascular hemolysis

A

antibodies (IgG)

71
Q

_____ and _____ antigens (especially anti-D) are most important in the erythroblastosis fetalis disorder

A

ABO and Rh antigens (especially anti-D)

72
Q

to prevent hemolytic disease of newborns, Rh-negative mothers are given __________ within 72 hours of delivery of an Rh-positive fetus

A

anti-D (Rhogam)

73
Q

anti-D binds to the _________ fetal cells and removes them from the maternal circulation before the mother can generate an antibody response and become sensitized

A

Rh-positive

74
Q

______________ disease occurs in group A and B infants born to group O mothers

A

ABO hemolytic

75
Q

what are the characteristics of Hemolytic transfusion reactions?

A
  • intravascular hemolysis
  • transfusion of incompatible red cells into a sensitized patient results in binding of antibody (in patient) to antigen (transfused RBC)
76
Q

what are the effects of hemolytic transfusion reactions?

A

Activation of coagulation cascade with bleeding, renal failure, shock, and death can occur

77
Q

what are the general characteristics of Autoimmune hemolysis ?

A
  • extravascular hemolysis

- Patient makes antibodies to his/her own RBCs

78
Q

________________ neutrophils may be seen secondary to the delay in mitotic division during megaloblastic anemia

A

Hypersegmented

79
Q

how does a Cardiac valve prosthesis cause hemolysis?

A
  • intravascular hemolysis
  • Red cells are disrupted by physical trauma as they pass through areas of turbulence and abnormal pressure related to abnormal valve function
80
Q

what happens during disseminated intravascular coagulation?

A
  • RBCs are lysed as they pass through fibrin clots/strands in the microcirculation.
  • Loss of large portion of membrane produces schistocytes.
81
Q

list the features of malaria:

A
  • intravascular hemolysis
  • Parasites infect RBC and cause lysis of RBC during maturation.
  • Varying degrees of intravascular hemolysis are experienced by individual patients.
82
Q

what RBC diseases result from nutritional deficiencies?

A
  • Iron Deficiency Anemia

- Vitamin B12 and Folate Deficiency

83
Q

_________ is the most common cause of anemia worldwide

A

Iron deficiency

84
Q

what happens to RBC’s when there is a shortage of iron?

A

Red blood cells become smaller (microcytic) and contain less hemoglobin (hypochromic) than usual

*note: these are the same characteristics as RBC’s during Thalassemia (both conditions= lack of funct Hemoglobin)

85
Q

describe the progression of anemia due to iron deficiency?

A

Anemia develops insidiously

remarkably low levels of hemoglobin can be tolerated with minimal symptoms

86
Q

what type of deficiency causes Megaloblastic anemia?

A

Vitamin B12 and folate

87
Q

Both B12 and folate are involved either directly or as cofactors in the synthesis of ________

A

thymidine

88
Q

________________ neutrophils may be seen secondary to the delay in mitotic division during megaloblastic anemia

A

Hypersegmented

89
Q

Patients with __________ anemia have autoantibodies directed against intrinsic factor

A

pernicious

90
Q

what 2 disorders are associated with decreased red blood cell production?

A

Aplastic anemia

Myelophthisic anemia

91
Q

name the characteristics of Aplastic anemia:

A

Production of all cellular elements of the blood (red cells, white cells, and platelets) is markedly decreased (pancytopenia)

92
Q

what causes aplastic anemia?

A

Over half of the cases have no known predisposing cause (idiopathic)

  • but viruses (hepatitis), drugs (chloramphenicol) and toxins (benzene, radiation) have been implicated
93
Q

Clinical problems of aplastic anemia result from what?

A

anemia (weakness, fatigue), leukopenia (infections), and decreased platelets (bleeding)

94
Q

The opposite of anemia is __________

A

polycythemia

95
Q

what causes Relative polycythemia?

A

occurs with hemoconcentration from dehydration, vomiting, diarrhea, or excessive use of diuretics

96
Q

Primary absolute polycythemia occurs when what occurs?

A

neoplastic proliferation of red cells (polycythemia vera)

97
Q

secondary absolute polycythemia occurs when what occurs?

A

increased erythropoietin production

  • Cyanotic heart disease, pulmonary disease, living at high altitudes, erythropoietin-producing tumors
98
Q

what causes Myelophthisic Anemia ?

A

Bone marrow replaced by tumor (metastasis or myeloma) or fibrosis

99
Q

what is the characteristic shape of RBC’s during Myelophthisis Anemia?

A

RBC’s seen as “teardrops” on blood smear

100
Q

Along with RBC count, what else is reduced during Myelophthisis Anemia?

A

Platelets are often also decreased

gen-path 2 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions