Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Heme Midterm 1 > Hemoglobin Disorders > Flashcards

Hemoglobin Disorders Flashcards

(62 cards)

Start Studying
1
Q

Thalassemia definition

A

genetically heterogeneous conditions resulting from imbalance between amounts of alpha and beta globin chains

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

What type of mutations occur with alpha chains?

A

full deletions

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

What type of mutations occur with beta chains?

A

point mutations

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

Beta0 versus Beta+ thalassemias

A

0 means no beta chains produced and + means some produced still

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

Beta Thalassemia Major name and genotype

A

Cooleys anemia B0/B0

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

symptoms of beta thalassemia major

A

splenomegaly (can be massive), bone deformities, anemia, and iron overload

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

How to diagnose beta thalassemia major?

A

all a4 tetramers

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

what do alpha 4 tetramers in beta thalassemis major cause?

A

ineffective erythropoiesis or intramedullary hemolysis, and destruction of produced RBCs

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

intramedullary hemolysis

A

destruction of RBC precursors in bone marrow

seen in beta thalassemia major

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

why splenomegaly in beta thalassemis major?

A

sequesteration of RBCs that are not functional due to a4 tetramer Hb

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

why iron overload in beta thalassemia major?

A

transfusions required and give some iron

iron hyper absorbed in gut too

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

how to treat beta thalassemia major?

A

transfusions and chelation of iron

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

beta thalassemia minor characteristics

A

heterozygous state with a normal and problematic allele

usually asymptomatic with microcytic RBCs and elevated RBC count

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

how to spot beta thalassemia minor?

A

best way is to look for delta or HbA2 in electrophoresis because lack of beta will upregulate production of the delta chain for Hb

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

cis and trans two gene deletions for alpha thalassemia

which population has which one?

A

cis is –/aa common in asians

trans is a-/a- common in AA

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

one gene alpha thalassemia characteristics

A

asymptomatic, not anemic, normal

very prevalent though

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

two gene alpha thalassemia characteristics

A

microcytosis, mild anemia

electrophoresis of adult is normal

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

Hemoglobin Barts

A

gamma4 Hb…due to hypoxic enviro and with two alpha thalassemia will make these tetramers

will see on electrophoresis for newborn

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

Hemoglobin H disease Thalassemia characteristics

A

a-/–

known to be beta4 tetramers

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

CBC characteristics of hemglobin H disease

A

MCV low, Hb low, MCH low, high RDW

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

What happens to hemoglobin H?

A

as it ages it turns into heinz body cause it is unstable and it is eaten…bite cell formation….splenomegaly common in hemoglobin H

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

Hydrops fetalis thalassemia characteristics

A

a is –/–…so make gamma4 tetramers or hemoglobin Barts
in utero still birth death at 25 weeks

treated by bone marrow transplant or transfusions

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

hemoglobin C mutation change

A

6th AA in beta chain changed from glutamate to lysine

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

hemoglobin C smear findings

A

target cells and hemoglobin C crystals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Gardos Ion channel in sickle cell disease?
abnormal Hb/membrane interactions activate the channel and lead to cellular dehydration in sickle cell
26
do sickle cells adhere to endothelial cells regularly? if not what is the risk?
no...creates risk of downstreak ischemia
27
What is SC sickle disease?
this is when you have a sickle trait and a hemoglobin C trait...heme C causes worse dehydration of cells and leads to worse sickling
28
Sickle-B0 thalassemia
sickle and B0 thalassemia combined...cannot distinguis from regular SS sickle
29
Sickle-B+ thalassemia
sickle and B+ thalassemia so a bit milder since you have some normal Hb being made
30
what happens to sickle cell patient spleen?
it is typically inactive and has infarcted by adulthood
31
What may be cause of Hb count dropping below sickle cell patients normal anemic level?
parvovirus B19 | splenic or hepatic sequestration, acute chest syndrome
32
why do sickle cell patients have leukocytosis and thromobocytosis?
spleen not there to take them out
33
thrombocytosis leads to what risk in sickle cell patients?
more venous clots
34
Splenic sequestration crisis in sickle cell kids
outflow vessels of spleen are blocked with sickle cells and the spleen blows up with blood have severe anemia and splenomegaly treat with small transfusion
35
aplastic crisis in sickle cell patient
parvovirus B19 prevents marrow from production so have rapid anemia
36
painful crisis in sickle cell patients
vaso occlusion of flow to bones..leads to bone and joint pain
37
trigger of painful crisis in sickle cell patients
exercise, dehydration, infection, cold, stress, menstruation, surgery, pregnancy
38
common infections in sickle cell
encapsulated organisms cause of splenectomy
39
in iron chelation therapy of sickle cell patient, what two organisms can cause problems?
yersinia and vibrio
40
what organism commonly causes osteomyelitis and septic arthritis in sickle cell?
salmonella
41
acute chest syndrome in sickle cell definition
hypoxemia, new infiltrate on chest Xray, new fever and chets pain, acute worsening anemia
42
what two organisms lead to infection commonly causing acute chest syndrome in the sickle cell?
chlamydia and mycoplasma
43
how can a fat embolism lead to acute chest syndrome in sickle cell?
necrotic bone marrow leads to fat deposits in the lungs...
44
how to treat acute chest syndrome in sickle cell patient?
need early detection antibiotics and oxygen transfusion to lower HbS
45
pulmonary hypertension in sickle cell patient characteristics
very common, mechanism is unknown, leads to death in 2 years by dyspnea chest pain and hypoxia, no good treatment besides prevention
46
what is the reason for Stroke in sickle cell patients? what is age of onset?
not artherosclerosis but is due to disordered blood vessels usually around age 5
47
how to treat stroke in sickle cell patient?
acutely use exchange transfusions and chronically use regular transfusions to prevent further strokes
48
how can we prevent strokes in young patients with sickle cell?
doppler of the head will show narrowing of vessels in cranium and can tell doc to give chronic regular transfusions to prevent stroke
49
simple transfusion
give red blood cells
50
exchange transfusion in sickle cell
give red blood cells and remove red blood cells to titrte to certain percent of HbS
51
rule about transfusions in sickle cell
do not let hemoglobin get above 10....one unit raises it by 1 high Hb raises viscosity of blood and increases risk of stroke in sickle cell
52
what type of transfusion for stroke, acute chest, and pre surgery?
stroke is exchange and others are simple
53
What are two complications of transfusions in SCD?
iron overload and allo-immunization
54
what does iron overload cause after a transfusion in SCD? how do you treat it?
organ failure..heart liver and endocrine chelation
55
allo-immunization in transfusion for SCD?
african americans have less RBC antigens, so need to give blood without C, E and Kell red cell groups so they do not react
56
Isothenuria in SCD
cannot concentrate urine because of renal papillary necrosis (no oxygen)
57
Avascular necrosis in SCD
affects heads of femurs and humeri, shoulder and hip pain
58
priapism in SCD
occludes outflow of penis...long erections
59
Hydroxyurea mechanism for SCD treatment
causes switch from beta chain to gamma chain so patient makes more fetal hemoglobin
60
effects of hydroxyurea on SCD
``` increases Hb reduces sickle cell pain crises reduces acute chest syndrome prevent pulmonary hypertension reduces mortality ```
61
should you give hydroxyurea to pregnant?
NO
62
side effect of hydroxyurea
bone marrow suppression so need to watch white cell count

Heme Midterm 1 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions