Sickle Cell Disease Flashcards

1
Q

What is the lifespan of RBCs?

A
  • 90-120 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is sickle cell disease?

A
  • Group of inherited RBC disorders resulting from a genetic mutation in the genes that encode hemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is hemoglobin S?

A
  • RBCs that contain abnormal hemoglbin is called hemoglobin S or sicke hemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does hemoglobin S causes and what happens after?

A
  • It causes RBCs to be rigid with a concave “sickle” shape
  • Sickled RBCs burst (hemolyze) after 10-20 days, which causes anemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which population is mostly affected by SCD?

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

When does symptoms of SCD develop? Why?

A
  • 2-3 months after birth
  • A fetus or young infants have RBCs with fetal hemoglobin (HgbF), which blocks the sickling of RBCs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is vascular occlusion and its complications?

A
  • Vascular occlusion prevents oxygen from reaching the tissues, causing them to become ischemic
  • This can lead to different types of sickle cell crises. The mos common is vaso-occlusive crises (VOC), or acute pain crisis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

If the pain is in the chest and there is evidence of a pulmonary infection, it is called ___.

Fill in the blank

A
  • Acute chest syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are chronic complications of SCD?

A
  • Pulmonary HTN
  • Renal impairment
  • Chronic pain
  • Avascular necrosis (bone death)
  • Leg ulcers
  • Gallstones
  • Pregnancy complications
  • Retinopathy
  • Recurrent priapism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are acute complications of SCD?

A
  • Vaso-occlusive crisis (acute pain crisis)
  • Acute chest syndrome
  • Anemia
  • Cholecystitis
  • Infection
  • Multiorgan failure
  • Priapism
  • Spleen sequestration
  • Stroke
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which encapsulated organisms is an healthy spleen particularly responsible to clear?

A
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Neisseria meningitidis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens to the spleen in SCD?

A
  • It becomes fibrotic and shrinks in size due to repetitive sickling and infarctions
  • This causes functional asplenia (decreased or absent spleen fx)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Patients with functional asplenia are at an increased risk of ___ ; they require ___ and ___.

Fill in the blanks

A
  • Serious infections
  • Immunizations
  • Prophylactic antibiotics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the non-drug treatment for SCD?

A
  • Blood transfusions
  • Bone marrow transplantation (the only cure)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the goal Hgb level when administering chronic blood transfusions?

A
  • Should be no higher than 10 g/dL post-infusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

T/F: One of the risks of blood transfusions is iron overload and chelation therapy can be administered to remove excess iron

A

TRUE

17
Q

What are drug treatments for SCD?

A
  • Immunizations
  • Antibiotics
  • Analgesics
  • Hydroxyurea (prevent/reduce complications)
  • Chelation therapy (manage iron overload)
18
Q

__ and __ due to S.pneumoniae, H. influenzae, N. meningitidis can occur.

A
  • Sepsis
  • Meningitis
19
Q

What reduces the risk of death from invasive pneumococcal infections in young children?

A
  • Prophylactic penicillin
20
Q

What is the treatment for infants who screen positive for SCD at birth?

A
  • Twice daily penicillin and treated until age 5 years
21
Q

What are routine childhood vaccine series for SCD?

A
  • Haemophilus influenzae type B (Hib)
  • Pneumococcal conjugate (PCV13, Prevnar)
22
Q

List additional vaccines for functional asplenia

A
  • Meningococcal conjugate series plus routine boosters
  • Meningococcal serogroup B (Bexsero, Trumenba) (at age >=10 years)
  • Pneumococcal polysaccharide (PPSV23, Pneumovax 23) (at age >=2 years, booster 5 years later and at age >=65 years)
  • Pneumococcal conjugate (PCV13, Prevnar) x1 in any patient >=6 years of age, if never received as a part of routine childhood series
23
Q

Patients with severe pain and VOC will require ___ administration of ___ or patient-controlled analgesia (PCA)

Fill in the blanks

A
  • IV
  • Opioids
24
Q

What is hydroxurea? What is it used for?

A
  • Hydroxyurea is a disease-modifying drug that stimulates production of HgbF
  • Long term use reduces the frequency of acute pain crises, episodes of acute chest syndrome and the need for blood transfusions
  • It is indicated for adults with >=3 moderate-to-severe pain crises in one year
25
Q

Hydroxyurea - BWs, warnings, monitoring

A

Boxed Warnings
* Myelosuppression

Warnings
* Fetal toxicity

  • Contraception required during treatment and after discontinuation
  • Hazardous drug: wear gloves when dispensing and wash hands before and after after contact
  • Folic acid supplementation is recommended to prevent macrocytosis
  • Avoid live vaccinations

Monitoring
* CBC with differential

  • Round doses up to the nearest capsule size
26
Q

Hydroxyurea - DDIs

A
  • Do not use hydroxyurea with pimecrolimus, tacrolimus and other drugs that cause myelosuppression (e.g., clozapine, deferiprone, leflunomide, natalizumab, tofacitinib)
27
Q

Other drugs that are used for SCD

A
  • L-Glutamine
  • Voxelotor - inhibits HgbS polymerization
  • Crizanluzumab
28
Q

Iron chelation treatment drugs

A
  • Deferoxamine - not in PO formulation
  • Deferasirox
  • Deferiprone