Red Cell Abnormalities and Hemoglobin Disorders

Question 1

Hemoglobin starts in the _____ stage?

Answer 1

Erythroblast

Question 2

Polycythemia

Answer 2

Too many red cells in the blood

Question 3

MCV

Answer 3

mean corpuscular volume = size of cells

Question 4

Average life span of a RBC?

Answer 4

120 days. Become fragile and are destroyed in the spleen.

Question 5

___% of the body’s RBC’s is produced every day

Answer 5

1%

Question 6

What is the fate of the porphyrin portion of hgb when it is destroyed?

Answer 6

Converted into the bile pigment, bilirubin, which is released into the blood and secreted through the liver with bile.

Question 7

Sickle cell anemia

Answer 7

Point mutation of valine for glutamic acid in the beta chain of a hemoglobin molecule.
Transmitted by recessive inheritance

Question 8

SIckle cell trait

Answer 8

Heterozygote with one sickle cell gene. 40 - 45% of hemoglobin is HbS. Not likely to sickle, generally asymptomatic

Question 9

Sickle cell disease

Answer 9

Homozygous recessive. 80 - 95% of hemoglobin in HbS. Concentration of HbS correlates with risk for sickling.

Question 10

SIckle Cell Epidemiology

Answer 10

Affects .1 - .2% of african americans (disease)

10% of african american have the trait

Question 11

Sickle cell pathophysiology

Answer 11

At low oxygen tension, HbS becomes sickled. SIckling occurs as a result of elongates crystals inside RBC’s.

• Makes it almost impossible for the cell to pass through capillaries.
• Crystals rupture RBC’s, leading to anemia

Question 12

What causes the sickling?

Answer 12

Anything that may reduce the affinity of hgb for oxygen.

- Hypoxia from altitude, cold, stress, exertion, acidosis

Question 13

SIckle cell manifestation

Answer 13

Pain and organ failure from occlusion
Severe hemolytic anemia
Chronic hyperbilirubinemia
Acute pain in any part of the body
Infarction can cause organ damage
Swelling of hands and feet
Acute chest syndrome

Question 14

Acute chest syndrome

Answer 14

Leading cause of death in sickle cell disease.
1. Red cell sickling and pulmonary capillary vessel occlusion.
2. Pulmonary infarction and atypical pneumonia
3. Pulmonary infiltrates, SOB, chest pain, cough
4, Resp. insufficiency with hypoxia, exacerbates sickling.

Question 15

Is prenatal screening available for sickle cell?

Answer 15

yes

Question 16

SIckle Cell Mgmt

Answer 16

NO known cure
Avoid situations that can precipitate sickling
Treatment aimed at reducing symptoms
- Pain control, hydration, infxn tx, blood transfusions

Question 17

Sickle cell prophylaxis

Answer 17

• Administration of penicillin from 2 months to 5 years of age.
• Full immunization
• Hydroxyurea (promotes fetal hgb)

Question 18

Alpha-Thalassemia

Answer 18

Most common is asians, blacks

Impaired production of alpha globin chains, which leads to a relative excess of beta globin chains.

Question 19

Beta-Thalassemia

Answer 19

Mediterranean anemia (italy and greece, blacks)
Impaired production of beta globin chains, which leads to a variable excess of alpha globin chains.

Question 20

How does thalassemia present?

Answer 20

Hypochromic microcytic anemia.
Normal RDW
Decreased RBC count
Normal ferritin

Question 21

What diagnoses Beta thalassemia?

Answer 21

Heinz bodies in bone marrow.

Question 22

What is the most prevelant thalassemia?

Answer 22

Beta thalassemia trait/minor

Question 23

Major targets of lead toxicity

Answer 23

RBC’s (microcytic, hypochromic anemia)
GI tract
Kidneys
Nervous system

Question 24

What will you see on a blood smear in lead poisoning?

Answer 24

Basophilic Stippling

Question 25

Other lead toxicity complications

Answer 25

Lead collic (abd pain)
Lead lines (metaphysis of bones on kids)
Low IQ, poor classroom performance
Kidney damage

Question 26

Lead toxicity tx

Answer 26

Remove the lead source

Chelation (for heavy metal poisoning)

Question 27

Acidosis causes….

Answer 27

Less affinity for oxygen. Oxygen is released from hgb.