Diseases of RBCs Flashcards
(88 cards)
1
Q
Characteristics of Pathologic Cold Agglutinins.
A
- Broad thermal range
- Spontaneous autoagglutination at RT
- Titer >1,000 at 4 degrees
2
Q
Cryoglobulinemia:
-Blood smears
A
Pale purple, cloudy aggregates of protein
3
Q
Stomatcoytic type of HE (SAO) facts (2).
A
- Band 3 protein defect
- Protection against P. vivax malaria
4
Q
At what % of total Hi does cyanosis occur?
A
10% of total Hb (or 1.5 G/dL)
5
Q
Thalassemic indices: RDW
A
Normal to slight increase
*Markedly INCREASED in IDA
6
Q
What is the % HbF at 6 months; 1 year?
A
- <10%
- <5%
7
Q
What causes PCH?
A
-IgG biphasic hemolysin (Donath-Lansteiner Ab)
8
Q
Hereditary persistence of HbF (HPFH) is caused by what?
A
Delayed switch from gamma (y) to beta or delta chains
9
Q
What and where are Type I Cryoglobulins found?
A
- Monoclonal Immunoglobulins
- MM or Waldenstrom
10
Q
MC etiology in Hereditary Stomatocytosis.
A
Abnormal Na+/K+ permeability
*Ass w/ Rh null phenotype
11
Q
Hereditary Spherocytosis (HS) gene mutation.
A
ANK1 (ankyrin)
Autosomal Dominant
12
Q
T/F: Single gene deletions are asymptomatic with a normal CBC and normal electrophoresis.
A
True
13
Q
Lab findings in G6PD.
A
- Poikilocytosis, bite cells, blister cells
- Heinz bodies (w/ supravital dyes)
- Extravascular hemolysis (Jaundice, Increased LD)
14
Q
Explain the Donath-Landsteiner Test.
A
2 Vials of blood
- Vial 1 at 37; Vial 2 at 4 for 30 minutes
- both at 37 for 30 minutes
- Positive test - Hemolysis in Vial 2
15
Q
What are the findings in Hb Bart?
A
- Severe Hemolytic anemia
- Hb Bart on electrophoresis
16
Q
Secondary CAIHA is a transient condition associated with infection. Which organisms is associated with:
- IgM anti-I
- IgM anti-i
A
Mycoplasma pneumonia (anti-I) EBV (anti-i)
17
Q
What are Type II Cryoglobulins made up of?
A
Mixture of 2 polyclonal Igs
18
Q
Thalassemic indices: P. Smear
A
- Microcytosis
- Target cells
- Basophilic stippling
19
Q
The Donath-Landsteiner Ab has specificity for what?
A
Anti-P
20
Q
HbC disease (homozygous CC) Hb ratios
A
HbC - 90%
HbF - 7%
HbA2 - 3%
HbA - 0%
21
Q
Hemoglobin Lepore runs with what on alkaline gel?
A
HbS, usually only 15% of total Hb
*Actual HbS is rarely present at this quantity, so suspect Lepore in this scenario
22
Q
3 alpha gene deletions result in ___ disease.
A
HbH
23
Q
How many gene deletions are result in alpha-thalasemia TRAIT; and what are the findings?
A
- 2 gene deletions
FINDINGS:
-thalassemic indices
-Normal HbA2 percentage
24
Q
4 alpha gene deletions result in ___ disease.
A
Hb Bart
25
T/F: HbF exerts an inhibitory effect on HbS polymerizaiton.
True
26
What causes Cold Autoagglutinin disease (CAD)/CAIHA?
-IgM antibodies to anti-I (most commonly)
27
Average lifespan of HbSS RBC
17 days
28
HbG and HbD run with what on alkaline gel?
HbS (do sickle cell screen or citrate gel)
29
What are causes of secondary WAIHA? (70% of cases)
- Hematolymphoid (CLL/SLL)
- Inherited immunodeficiencies (CVID,IgA,etc.)
- Collagen vascular disease
- Thymoma
30
The membrane defects in PNH is caused by what?
Decreased Glycosyl Phosphatidyl Inositol (GPI) anchors
31
Cryoglobulinemia is a systemic immune complex disease characterized by a distinctive clinical syndrome, what are the symptoms? (7)
- Palpable purpura (leukocytoclastic vasculitis)
- Arthralgia
- Hepatosplenomegaly
- Lymphadenopathy
- Anemia
- Sensorineural deficits
- Glomerulonephritis
32
Beta-Thalasemia trait (Heterozygotes) has what changes in Hb ratios? (what if also Iron Deficient)
HbA2 - >3.5%
HbF - Normal to INcreased
*If iron deficient the HbA2 may be normal
33
alpha or beta Thalassemia??
Manifestations are present at birth.
- Alpha
| * Beta become evident >6 months
34
What causes a warm autoimmune hemolytic anemia (WAIHA)?
warm reacting IgG autoantibody
35
3 types of Hereditary Elliptocytosis
- Common type (HPP; African Americans)
- Spherocytic type
- Stomatocytic type (Southeast Asian Ovalocytosis)
36
Sickle Cell Disease (genotype SS) Hb ratios.
HbS - >80%
HbA - 0%
HbA2 - 1-4%
HbF - 1-20%
37
Positive or Negative:
What is the DAT in WAIHA?
Positive (nearly ALL cases)
*usually polyspecific and anti IgG reagents
38
What is the presentation of PCH?
Paroxysmal episodes of hemoglobinuria associated with COLD Exposure
39
Which type of Cryoglobunimia is most commonly seen?
Type 2
40
HbSC disease Hb ratios
HbS - 50%
| HbC - 50%
41
Beta-Thalasemia
There is a total of _#_ copy of the __- gene on each chromosome __, for a total of __ productive genes.
1, Beta, 11, 2
*There i a total of on copy of the B gene (HBB) on chromosome 11, for a total of 2 productive genes.
42
G6PD inheritance
X-linked recessive
43
Sickle Cell Trait (genotype SA) Hb ratios.
HbS - 30-45%
HbA - 50-65%
HbA2 - <3%
44
Homozygotes (Beta-Thal) hs what Hb ratios?
HbF - 50-85%
HbA - little to NONE
HbA2 - Normal to INcreased
45
Hereditary Elliptocytosis/Ovalocytosis gene mutation.
Spectrin a-chain
Autosomal Dominant
46
Mutation in Hemoblobin Constant Spring
mutation in the alpha globin STOP codon; producing abnrmally long transcript
47
Which population is is most common in Paraxysmal Cold Hemoglobinuria (PCH) and what is it associated with?
- Children
- Post-Viral (Measles, Mumps, VZV, Mono)
*originally described in syphilis
48
Abnormality in Methemoglobin (Hi, hemiglobin)
Iron is in the Oxidized ferric (Fe3+) state instead of usual ferrous (Fe2+) state.
Incapable of combining with Oxygen
49
HbSC disease manifestations
Between SS and SA
50
In alpha-thalassemia 1 (a0 thalassemia), chromosome 16 has __ deleted alpha genes. What race is this prevalent in?
- 2
| - Asians
51
What are Type II Cryoglobulin made up of?
Mixture of Monoclonal IgM and Polyclonal IgG
52
alpha-thalasemia:
There are __ copies of the __ gene on each chromosome __, for a total of __ genes.
2, a, 16, 4
*There are 2 copies of the alpha gene on each chromosome 16, for a total of 4 genes.
53
What characteristic finding of PCH may be seen on P. smear?
Intraneutrophilic hemophagocytosis
54
What clinical condition is the MCC of Type II cryoglobinemia?
HCV
55
What is seen in renal biopsies of cryoglobulinemia?
- Membranoproliferative Glomerulonephritis (MPGN)
| * Deposits may produce the appearance of thrombotic microangiopathy
56
How are Beta-Thal Major and Intermedia distinguished ?
Transfusion dependence (MAJOR)
57
Characteristics of Nonpathologic Cold Agglutinins.
- React most strongly at 4, up to 22 degrees
| - Titer <64 at 4 degrees
58
Thalassemic indices: MCV/RBC count ratio
<13 favors thalassemia
*>15 favors IDA
59
What antigens does the pathogenic antibody in WAIHA usually have broad reactivity with?
Rh Antigens
60
HbC disease manifestations.
- Mild hemolytic anemia
- Splenomegaly
- Target cells (numerous)
- Hexagonal or Rod-shaped CRYSTALS
61
What is the abnormality in Hb Lepore?
fusion between Delta and Beta genes
62
Intravascular or Extravascular Hemolysis in WAIHA?
Extravascular
63
Hemoglobin S alteration.
B6 glu->val
64
HbG is a defect in what chain?
Alpha
65
What are the findings in HbH?
- Hemolytic anemia
| - Fast moving HbH on electrophoresis
66
Thalassemic indices: RBC count
Normal to Increased RBC count
67
What is the % of HbF at term?
30-40%
68
Most alleles with thalassemic phenotype result from what type of a mutation?
Point
69
HbD is a defect in what chain?
Beta
70
T/F: Paroxysmal Nocturnal Hemoglobinuria (PNH) is an acquired clonal red cell disorder.
True
71
Incidence of Sickle Cell Trait in AA.
10%
72
What is the mutation/gene associated with PNH?
-PIG-A on X chromosome
73
What is the 2nd MC abnormal Hemoglobin worldwide (after S)?
HbE (B26 glu->lys)
| *Southeast Asia common
74
What is the treatment for Methemoglobin?
Methylene blue, reduces Hi to Hb
75
The leukocyte alkaline phosphatase (LAP) score is (increased/decreased) in PHN.
Decreased
76
Pyruvate Kinase (PK) deficiency findings & Inheritance
- Chronic hemolysis (varied severity)
- Echinocytes (dessicocytes)
- Extravascular Hemolysis
- Audosomal Recessive
77
What is the % of HbF in Combine HbSS/HPFH and what are symptoms?
- 25%
| - MILD symptoms (No anemia or vasoocclusive episodes)
78
HS lab values.
- MCHC Increased
- Reticulocyte count Increased
- MCV & MCH normal
79
Fluorescent aerolysin (FLAER), obtained from what, binds specifically to GPI?
Aeromonas hydrophila
80
Flow cytometry markers for PNH:
- RBCs
- Granulocytes/monocytes
- CD55,59
| - CD14,15,16,33
81
Combined Sickle cell (HbSS) and HPFH is found in what percentage of homozygous HbSS?
1 percent (~1 in 100)
82
Definition of cryoglobulins.
Immunoglobulins that precipitate reversibly at Low Temperatures
83
How do you detect cyroglobulins?
- Blood drawn at 37 and kept till clotted
- Centrifuge at 37
- Serum stored at 4 for >3 days
- Centrifuge at 4
- Any precipitate that forms is cryoprecipitate
- Electrophoresis for characterization
84
In alpha-thalassemia 2 (a+ thalassemia), chromosome 16 has __ normal and __ deleted alpha gene. It is the most common genotype in what race?
- 1, 1
| - African Americans
85
After age 2 what is the normal % of HbF?
<1%
86
In all tissues, what is the basic pathologic lesion in cryoglobulinemia?
-what is seen on EM?
Vasculitis
*EM - Subendothelial immune complex deposits with a fibrillary or tubular structure in a fingerprint like pattern
87
MOA of hydroxyurea in SS.
Increase HbF and lessen severity of SS.
88
PNH may evolve into what?
- Aplastic Anemia (and or)
| - AML
