Hematopathology- Schoenwald Flashcards

1
Q

RBC disorders: Describe the very basic pathology of anemia.

A

A decrease in RBCs

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

RBC disorders: What are the three mechanisms of anemia?

A
  • Blood loss (acute or chronic)
  • Decreased production of RBC
  • Increased destruction of RBC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

RBC disorders: Describe hemolysis

A

Destruction of RBCs

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

RBC disorders: How do you evaluate for anemia?

A

Size and hemoglobin concentration (MCV and MCHC)

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

Classification of anemias: In blood loss (acute) what will you see on evaluation of the RBCs? (initially and later).

A
  • Initially: normocytic normochromic

- Later: Hypochromic, reticulocytosis

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

Ex’s of blood loss (acute) that can cause anemia? (list 3)

A
  • Acute volume depletion.
  • RBC reduction due to fluid influx
  • Rapid RBC regeneration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

classification of anemias: RBCs of blood loss (chronic)?

A

Hypochromic (means the RBC’s have less Hgb than normal)

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

Classification of anemias: Characteristics of blood loss (chronic)?

A

Reduced Iron stores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

lassification of anemias: What types of anemia are under the category of increased destruction?

A
  • Hemolytic anemias
  • Immunologic
  • Mechanical
  • Hereditary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Classification of anemias: Characteristics of hemolytic anemias?

A
  • Features of hemolysis

- Splenomegaly

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

Classification of anemias: Characteristics of immunologic anemias?

A
  • Autoantibodies against RBC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lab finding (pertaining to cells) associated with immunologic anemias?

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

Classification of anemias: RBCs of Mechanical anemias?

A

Shistocytes

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

classification of anemias: examples of mechanical anemias?

A
  • HUS (hemolytic uremic syndrome)
  • TTP (thrombocytopenic purpura)
  • Trauma-valve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Classification of anemias: RBC (types) of hereditary anemias? (list 5)

A
  • Spherocytosis
  • Elliptocytosis
  • Sickle cell
  • Hypochromic
  • Microcytic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Classification of anemias: Characteristics of hereditary anemia?

A
  • RBC membrane and cytoskeleton deficiency
  • Hemoglobinopathies: sickle cell, thalassemia
  • Enzyme deficiencies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Classification of anemias: What types of anemia are categorized as deficient erythropoiesis?

A
  • “Stem cell” defect

- Maturation defect

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

Classification of anemias: RBCs of “stem cell” defect anemia?

A
  • Normocytic, normochromic

- Normocytic, mildly macrocytic

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

Classification of anemias: Examples of “stem cell” defect anemias (list 2)

A
  • Aplastic anemia

- Pure red cell aplasia

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

Classification of anemias: RBCs of maturation defect anemia?

A
  • Megaloblastic
  • Anisocytic
  • Hypochromic
  • Poikilocytic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Classification of anemias: Characteristic of maturation defect anemia?

A
  • Pernicious anemia
  • Folate deficiency
  • Iron deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Mechanisms of anemia: Examples of blood loss that cause anemia?

A
  • Acute: trauma

- Chronic: GI, malignancy, menstrual bleeding

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

What are schistocytes?

A

fragmented RBCs

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

Mechanisms of anemia: Examples of external factors that could increase destruction of RBCs?

A
  • Ab mediated transfusion Rx
  • Erythroblastosis fetalis
  • Autoimmune
  • Trauma to RBC
  • Infection
  • Sequestration in spleen.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Mechanisms of anemia: Examples of hereditary internal factors that could increase destruction of RBCs?
- Cytoskeleton defect (hereditary spherocytosis) - Structurally abnormal Hgb (sickle cell, thalassemia) - Enzyme deficiency (G6PD)
26
Mechanisms of anemia: Other than external and hereditary internal factors, what are other sources of increased destruction of RBCs?
- Acquired defect - Paroxysmal nocturnal hemoglobinuria (= an acquired, life-threatening disease in which hemolysis, thrombosis, and anemia occur)
27
Describe paroxysmal nocturnal hemoglobinuria - Etiology? - characterized by which 3 things?
Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired, life-threatening disease of the blood. The disease is characterized by destruction of red blood cells (hemolytic anemia), blood clots (thrombosis), and impaired bone marrow function (not making enough of the three blood components).
28
Paroxysmal nocturnal hemoglobinuria: Red cells are more prone to lysis by what mechanism?
Complement
29
Paroxysmal nocturnal hemoglobinuria: Condition results in what venous condition?
venous thrombosis
30
Paroxysmal nocturnal hemoglobinuria: CLinical signs?
- Episodic hemoglobinuria, 1st morning urine.
31
Paroxysmal nocturnal hemoglobinuria: How does venous thrombosis manifest?
- Hepatic - Portal - Mesenteric - Cerebral veins. (Harry potter makes cake)
32
Mechanisms of anemia: How can decreased production of RBCs occur?
- Disturbance of stem cells - Defective heme production - Defective DNA production - Destruction of bone marrow
33
Mechanisms of anemia: What is a condition that can cause a disturbance of stem cells?
aplastic anemia
34
Mechanisms of anemia: What are conditions that can cause a defective heme production? (list 2 ex's)
- IDA | - thalassemia
35
Mechanisms of anemia: What is a condition that would lead to defective DNA production?
- Vitamin B12 deficiencies | - Folic acid deficiencies
36
Mechanisms of anemia: What is a condition that could lead to a destruction of bone marrow?
metastatic tumor
37
Sites of removal of RBC from circulation: Extravascular site(s)?
- Phagocytic systems of spleen and liver
38
Sites of removal of RBC from circulation: Complications?
- Hemosiderin deposition in organs | - Jaundice and gallstones
39
Sites of removal of RBC from circulation: Why could jaundice and gallstones occur as a complication?
Results from elevated unconjugated bilirubin associated with hemolysis
40
Sites of removal of RBC from circulation: Intravascular source?
- Destruction of RBC in the vessel
41
Sites of removal of RBC from circulation: Intravascular complications?
- Acute tubular necrosis | - Jaundice and gallstones --> can occur due to increased unconjugated bilirubin
42
Why could acute tubular necrosis occur as a complication of intravascular removal of RBCs?
Due to hemoglobinemia
43
Lab findings in hemolysis of RBCs: Hgb/Hct?
Hgb decreased, Hct decreased
44
Lab findings in hemolysis of RBCs: Haptoglobin?
- Initially: increase | - Over time (net): Decreased
45
Lab findings in hemolysis of RBCs: Wy does haptoglobin decrease over time?
Because it keeps binding to that free heme circulating.
46
Lab findings in hemolysis of RBCs: LDH?
Increased lactate dehydrogenase (LDH) (it’s a liver enzyme and its inside RBCs) -and increased unconjugated bilirubin
47
Lab findings in hemolysis of RBCs: K+?
Increased potassium (since cells are breaking down and releasing potassium)
48
What conditions might you see spherocytes with?
- Hereditary spherocytosis | - Immune hemolysis
49
What conditions might you see schistocytes with?
- TTP | - HUS
50
What conditions might you see target cells with?
hemaglobinopathies
51
What conditions might you see teardrops with?
Myelofibrosis
52
What conditions might you see sickle cells with?
- Sickle cell | - Thalassemia minor with sickle cell
53
What conditions might you see Rouleaux with?
Rouleaux= "stacking of coins"--> - due to Increased globins or decreased albumin (multiple myeloma)
54
Clinical presentation of anemia?
- Pale skin - Fatigue - Shortness of breath - Chest pain - Syncope and dizziness
55
Lab values associated with an initial anemia assessment?
- MCV | - Reticulocyte count
56
What does an increased reticulocyte count imply?
- Bone marrow intact and able to produce RBC | - Acute blood loss or hemolysis
57
What does a decreased reticulocyte count imply?
- Primary bone marrow disorder OR - Deficiency in building blocks (iron, B12, folate)
58
MCV values: What are the categories of MCV?
- Microcytic - Normocytic - Macrocytic
59
MCV values: Microcytic? | Normocytic? Macrocytic?
Micro- < 80 fl Normo- 80-100 fl Macro- >100 fl
60
What are the microcytic anemias?
- Iron Deficiency - Thalassemia - Late stage anemia of chronic disease
61
Iron deficiency anemia: MCC in US? (list MC cause of blood loss in the US vs outside the US)
- GI blood loss or menstrual blood loss | - -Outside of US- due to poor nutrition
62
Iron deficiency anemia: Additional causes of IDA?
- Malabsorption | - Increased demand (pregnancy)
63
IDA labs: What would you look at?
- Ferritin - Serum iron - Iron stores in bone marrow - TIBC - RDW - Transferrin saturation
64
IDA Labs: Results
- Decreased ferritin (less than 30 is diagnostic of IDA))** - Decreased serum Iron - Decreased iron stores in bone marrow - Decreased transferrin saturation(ratio of serum iron to TIBC - Increased TIBC - Increased RDW
65
IDA labs: What is normal transferrin saturation?
>20%
66
IDA labs: What would the transferrin saturation look like in IDA?
<10%
67
Thalassemia--> is characterized by a deficient production of Hgb due to ______
--> mutation or complete loss of globin chain -There are 4 copies of the alpha globulin chain and 2 copies of beta globulin.
68
Alpha Thalassemia: Due to the complete loss of ____?
--->1 or more of the 4 copies of the alpha globulin chain gene
69
Alpha thalassemia: | -Loss of 1 copy of the gene= ?
silent (carrier)
70
Alpha thalassemia: loss of 2 copies=
alpha thalassemia trait (asymptomatic but MCV low)
71
Alpha thalassemia: loss of 3 copies=
``` HbH disease (marked anemia) **these pts have Sx ```
72
Alpha thalassemia: loss of 4 copies=
hydrops fetalis (stillborn)
73
Alpha thalassemia: | -demographic?
Prevalent in Africans and Asians
74
T/F: alpha thalassemia usually requires blood transfusions
False!! usually does not require blood transfusion
75
Describe Beta Thalassemia
Malfunction of gene due to mutation which result in **complete loss of the Hgb protein **Alpha chains are insoluble and result in intravascular hemolysis and ineffective erythropoiesis
76
Demographic: Beta thalassemia
Mediterranean descent
77
Beta thalassemia: Major - describe this condition? - requires ? - Onset?
=Skeletal abnormalities due to bone marrow expansion - -Usually onset after 6 months of age due to loss of Hgb F and transition to Hgb A - Tx: Requires life-long blood transfusions due to severe anemia
78
Beta Thalassemia: Minor - Describe this condition? (hgb and MCV values)? - Requires?
Hgb and MCV disproportionate-hgb 10/MCV 55 -Usually does not require transfusions
79
Beta Thalassemia: Labs?
- Decreased MCV (microcytic!!!! less than 80 fl) - Decreased hgb - Anisocytosis (change in size) - Poikilocytosis(change in shape)
80
Beta Thalassemia: Poikilocytosis shows?
-microcytes, target cells
81
Anemia of Chronic disease: anemia that occurs in the background of ______
chronic disease (ie Lung carcinoma, Hodgkin lymphoma, rheumatoid arthritis, infection-TB)
82
Anemia of chronic disease: Labs- initially? Late stage?
Initially, normocytic, | -late stage can be microcytic
83
Anemia of Chronic Disease: Labs (elevated lab values and decreased)
Elevated: levels of storage iron, **increased Ferritin Decreased: serum iron & decreased TIBC
84
Describe Anemia of chronic disease: - what happens with iron? - EPO?
- ->Cannot transfer iron from phagocytic cells to erythroid precursors - Through TNF and interferons erythropoietin is decreased
85
In a Pt with anemia of chronic disease, what protein is stimulated?
**Hepcidin is stimulated Hepcidin= protein that is key regulator of the entry of iron into circulation -->**impairs release of iron from storage
86
IDA: lab values
Elevated: TIBC Decreased: **Ferritin, Iron, Transferrin saturation
87
Thalassemia: lab values
All normal | **thalassemia is NOT an iron issue, it's a Hgb issue
88
Anemia of chronic disease: lab values
Elevated: Ferritin, transferrin saturation Decreased: Iron, TIBC
89
Macrocytic Anemia: describe this condition - Vitamin ___ deficiency? - MCV? - describe what happens to DNA - DNA shows ______
**Vitamin B12 deficiency -MCV >100 =Impaired DNA synthesis involving all bone marrow precursors, not just RBC -Impairment of DNA slows nuclear maturation but NOT cytoplasmic
90
Vit. B12 is needed for?
(cyanocobalamin) =for regeneration of tetrahydrofolate--> giving folate will correct a B12 anemia but does not treat the neurologic findings
91
A Pt presents with MCV >100. what labs should you check?
for macrocytic anemia work up you must check B12 levels, homocysteine and MMA levels
92
vit. B12 deficiency causes elevated levels of?
**homocysteine and methyl-malonic acid (MMA)
93
Complications of B12 deficiency
- Anemia, thrombocytopenia and leukopenia - Ineffective erythropoiesis - Neurologic deficiencies
94
Describe why B12 deficiency causes ineffective eythropoiesis
Adequate number of RBC precursors but many of them undergo apoptosis in bone marrow due to impaired nuclear maturation
95
List specific neurologic deficiencies that stem from B12 deficiency
=Peripheral neuropathy and spinal cord pathology | **note: this is NOT seen in Folate deficiency
96
Causes of B12 deficiency
- **Pernicious anemia - Nutrition (rarely) - Gastrectomy - Ileal disease - Diphyllobathrium latum infection –fish tapeworm
97
What is Pernicious Anemia
=Condition is due to antibodies against parietal cells or blocking antibodies or antibody against B12-IF(intrinsic factor) complex -Autoimmune gastritis, loss of parietal cells that causes loss of intrinsic factor (Parietal cells are in the stomach (so if they are attached, you don’t have as much B12 absorption In the stomach)
98
Clinical presentation of B12 deficiency
- **Pancytopenia (Defect is not just limited to RBC, you will see a decrease in all cells growing rapidly) - Loss of intestinal cells--> diarrhea and malabsorption - Peripheral neuropathy
99
B12 deficiency: KEY Lab findings
-Hypersegmented neutrophils on CBC (due to DNA impairment)
100
Folate deficiency: important differences from B12 deficiency
aka vitamin B9 deficiency--> megaloblastic anemia - Folate deficiency does NOT cause neurologic deficits - **Often due to dietary deficiency(US) - ->**alcoholism - Folate deficiency is NOT associated with pernicious anemia
101
Aplastic Anemia: describe this condition
=Decreased Production of cells, -it’s not associated with MCV - Anemia is due to absence of RBC in bone marrow - Also involves other hematopoietic cells - Likely due to suppression of stem cell function
102
T/F: splenomegaly is not seen with aplastic anemia
True, there is NO splenomegaly
103
What is a big problem associated with aplastic anemia?
Can convert to leukemia
104
Aplastic anemia: causes
-Idiopathic (50%) - Secondary to drug therapy: - Alkylating agents- ie chemotherapy - Chloramphenicol-antibiotic (old) - Benzene - Infections: parvovirus B19 (slpa cheek appearance), Epstein Barr Virus, HIV - Radiation - Genetic
105
Hemolytic Anemias ALL have:
- Increased RBC destruction(intravascular or extravascular - Increased erythropoiesis - Increased iron deposition in tissues-spleen and liver - Some cases have pigment gallstones (from increase in bilirubin
106
Hemolytic Anemias: Intravascular Hemolysis--> Key lab findings
-Decreased haptoglobin - Increased unconjugated(indirect) bilirubin - Increased LDH-markedly - **Positive urine hemosiderin and urine hemoglobin (brown urine)
107
Hemolytic Anemias: Extravascular Hemolysis--> Key lab findings
- Normal to slightly decreased haptoglobin (not as marked as with intravascular) - Increased unconjugated (indirect)bilirubin-usually more than intravascular - Normal to slightly increased LDH - **Negative urine hemosiderin and urine hemoglobin
108
What is the mechanism of increased unconjugated bilirubin in hemolysis?
Macrophages phagocytize RBCs--> inside the macrophage the RBC is degraded in lysosomes (heme + globin--> AA’s) Heme--> Fe and Porphyrin. Porphyrin--> unconjugated bilirubin--> exits macrophage and combines with albumin--> goes to hepatocyte--> unconjugated bilirubin--> is converted to conjugated bilirubin---> exits into biliary system(= gallbladder and bile ducts inside and outside the liver) -these Pts have discoloration of stool and urine Unconjugated and conjugated= total bilirubin
109
haptoglobins = _______ produced by the liver
Glycoproteins produced by liver
110
Haptoglobin: fx
Powerful free hemoglobin binding proteins
111
What happens to haptoglobin in hemolytic anemias?
- In hemolytic anemia, large release of free Hgb by breakdown of RBC, haptoglobin quickly binds to free hgb, and is rapidly broken down - ->***Results in decrease in haptoglobin as liver is unable to rapidly compensate to make more haptoglobin
112
Mechanism of Hemolytic anemia: Congenital?
- Enzyme deficiency (G6PD) - Defects of cytoskeleton (sperocytosis) - hemoglobinopathies (sicke cell and thalassemia)
113
Mechanism of Hemolytic anemia: Acquired?
- Antibody induced | - mechanical
114
Coombs Testing: Direct Coombs
aka direct antiglobulin test - Antibodies causing hemolysis are on the surface of the RBC - In lab, add antibody against IgG(on RBC)=agglutination of cells
115
Difference b/w direct coombs and indirect coombs test
- Direct coombs tests the Pts RBCs looking for hemolytic anemia, while Indirect coombs checks the Pts plasma, checking for antibodies that will react with transfusions - Direct coombs is more important for hemolytic anemias (the test will be Positive--- indicating there are antibodies causing hemolysis on the surface of the RBC) How to perform a direct coombs: in a lab, add antibody against IgG (onto RBCs)- if there is agglutination of the cells= + test
116
Describe and Indirect Coombs Test
-aka indirect antiglobulin test - Antibodies causing hemolysis are in the plasma but not on the RBC surface - In lab, serum tested with known RBC ag that antibody reacts to then antibody added=agglutination -Indirect coombs: antibodies causing hemolysis are in the PLASMA--> these tests are checking antibodies in the Pts plasma that could react with a transfusion (blood transfusion)
117
Antibody mediated destruction of RBCs: Isohemagglutinin
isohemagglutinin= what happens in RBC transfusion reactions (ie ABO or other type incompatibility, Rh positive - RBC transfusion reactions-ABO or other blood type incompatibility - Ertyhroblastosis fetalis--> RH incompatibility
118
Antibody mediated destruction of RBCs: Autoimmune (list 2 examples of anemias)
- Warm autoimmune anemia | - Cold autoimmune anemia
119
ABO transfusion reaction: antibody type is ____ mediated
IgM
120
An ABO transfusion reaction indicates an _____ _____
Intravascular hemolysis
121
ABO transfusion reaction leads to: (list complications)
- Intravascular hemolysis - Hemoglobinemia--> leading to acute renal failure & HIGH mortality rate (all the Hgb that was released, and decreased heme carrying ability leads to acute renal failure and high mortality)
122
ABO transfusion reaction: which antibodies are naturally occuring?
Anti A and Anti B IgM naturally occurring
123
Review Slide 43
on ABO typing
124
Non ABO transfusion reaction: antibody type? | -is usually which type of hemolysis?
- usually IgG - **Extravascular hemolysis--> antibody binds to RBC then complex is removed by spleen - Usually requires previous exposure to non ABO antigen (example Rh factor)
125
What Sx is associated with Non ABO transfusion reaction?
Jaundice (my notes: Non ABO transfusion reactions= usually not as lethal as ABO transfusion reactions BUT you do see a lot of jaundice)
126
Erythroblastosis Fetalis: describe this condition
=Maternal antibody against a fetal red -blood cell antigen Rh factor (made up of DCE ag) D potential for most potent reaction - Mom Rh factor(D) negative, 1st child D+=exposure, 1st child is okay - **Second child D+=erythroblastosis fetalis due to IgG present in mom, able to cross placenta and bind to fetal RBC=hemolysis
127
Erythroblastosis fetalis: clinical presentation
``` **=fetal hemolytic anemia Sx: -Hydrops fetalis -**Positive direct coombs -Unconjugated hyperbiliribinemia (severe) -Kernicterus ```
128
Kernicterus=
is a very rare type of brain damage that occurs in a newborn with severe jaundice. --> **causes mental retardation and DEATH
129
Hydrops fetalis=
SEVERE fetal edema
130
Erythroblastosis fetalis: Prevention
- Rh (D-) mothers are given RhD(anti D antibody) =Rhogam, during pregnancy - When fetal rbc cross into maternal circulation, Rhogam binds to them, masks the D ag from mom and prevents forming ab to it.
131
Warm Autoimmune Anemia=
=IgG vs self antigen reaction at 37⁰ C acts as opsonin - RBC removed by phagocytosis - Extravascular hemolysis
132
Warm Autoimmune Anemia: Sx
Present with anemia, jaundice,+/-splenomegaly
133
Warm Autoimmune Anemia: Labs
- Direct Coombs test positive, | - elevated retic count
134
Warm Autoimmune Anemia: etiology (primary and secondary)
- Primary-60% idiopathic | - Secondary: drugs (Penicillin, methyldopa, immune complex formation with drugs), B-cell neoplasm, lupus
135
Cold Autoimmune Hemolytic Anemia: describe this condition
-IgM binds to RBC at 30⁰ with complement, at 37⁰ IgM releases, cleaves C3b>opsonin
136
DIFFERENCE b/w warm and cold autoimmune anemia ?
-***Direct coombs is NEGATIVE in cold autoimmune hemolytic anemia & spherocytes are present
137
Cold Autoimmune Hemolytic Anemia: Causes--> Acute-self limited?
Mycoplasma pneumonia, EBV
138
Cold Autoimmune Hemolytic Anemia: Causes- Chronic?
- Idiopathic | - B cell neoplasms
139
Other causes of Hemolytic Anemia
- Mechanical valves - ITP, TTP, DIC - Malaria - Babesia
140
Babesia=
=an intracellular parasite that is endemic to the midwestern US (usually transmitted by a tick bite)
141
Hereditary causes of destruction of RBC: Categories (list 3)
- defect in cytoskeleton - structurally abnormal hemoglobins - enzyme deficiency
142
Hereditary Spherocytosis: describe this condition
=Defect in cytoskeleton of RBC - Mutation of gene of one of the proteins responsible for cytoskeleton matrix - RBC not as flexible and becomes trapped in spleen
143
Hereditary Spherocytosis: Sx
Jaundice and splenomegaly
144
Hereditary Spherocytosis: Labs
-direct coombs negative, increased osmotic fragility test(cell cannot swell in hypotonic solution),increased unconjugated bilirubin
145
Hereditary Spherocytosis: definitive tx?
Splenectomy resolves anemia
146
Structurally abnormal hemoglobin: Sickle Cell anemia Homozygous vs Heterozygous?
HbS= sickle cell disease (when they have all HgS)= Homozygous Sickle cell trait (NOT sickle cell dz)= Heterozygous--> 50% HbS
147
Sickle cell MC demographic
Africans 8% have trait(malaria protection) | -0.2% have disease(anemia)
148
AA substitution in Sickle Cell anemia (KNOW**)
“sticky” hemoglobin due to valine substitution for glutamic acid in Beta globin chain!!!!
149
What environments or conditions promote sickling in sickle cell anemia?
Dehydration and altitude promote sickling
150
Complications of Sickle Cell:
- anemia - Microvascular obstruction=ischemia and infarction - Increased erythropoiesis - Renal and pulmonary failure
151
Complications of sickle cell disease associated with Microvascular obstruction=ischemia and infarction
- Painful vaso-occlusive crisis caused by necrosis in bone marrow - Necrotic bone marrow can embolize to the lung= acute chest syndrome - Autosplenectomy (in some Pts spleen becomes non functioning)-increased risk of infection with encapsulated organisms - Priapism (a prolonged erection of the penis), cerebral infarcts
152
G6PD deficiency-Enzyme: describe this condition
=X linked recessive - Most common enzyme deficiency to cause hemolysis - **RBC unable to regenerate glutathione-normally helps to reduce oxidized substances
153
G6PD deficiency-Enzyme: demographic
Prevalent in Middle East and African descent
154
G6PD deficiency-Enzyme: Sources of oxidants (that can trigger an anemic episode in Pts)
-Antimalarial (primiquine), sulfonamides, aspirin, nitrofurantoin, viral hepatitis and fava beans
155
G6PD deficiency-Enzyme: key lab findings
-Heinz bodies and Bite cells (**Think Heinz ketchup (glucose 6-d) and bite cells
156
Polycythemia: describe this condtion
- Increased number of RBCs | - **hgb>60%**
157
Polycythemia: sx
red faces, headaches,
158
Polycythemia: Relative
hemoconcentration
159
Polycythemia: Primary
Polycythmia rubra vera=proliferation of RBC
160
Polycythemia: secondary
(ie occurring 2/2) Lung dx, cyanotic heart dx, erythropoietin producing tumors