Sickle cell disease

Question 1

Indications for transfusion in SCD

Answer 1

Severe, symptomatic anemia
Treatment of acute coronary syndrome
Prophylaxis of acute coronary syndrome (if patient has frequent life threatening ACS despie hydrea) 
Acute stroke
Acute multi organ failure
Preoperative transfusion

Question 2

Secondary CVA prevention in SCD

Answer 2

• chronic transfusions – Monthly simple or exchange transfusion
• ASA
• little evidence for statins or BP control
• NO role for anticoagulants

Question 3

acute chest syndrome presentation + clinical features

Answer 3

chest pain + fever/respiratory symptoms + SCD + new radiographic density on CXR + usually during vaso-occlusive episode

Question 4

Target Hgb S in red cell exchange (exchange transfusion)

Answer 4

Less than 30%

Question 5

Concept of red cell exchange

Answer 5

• Remove sickle cells and replace with healthy red blood cells

Question 6

Side effects of exchange transfusions

Answer 6

• Vasovagal reactions
• Allergic reactions

Question 7

Cause of flushing and hypotension in SCD patient getting exchange transfusion

Answer 7

ACE inhibitor reaction

Question 8

Management of priapism in SCD

Answer 8

First line = blood aspiration from the corpus cavernosum, followed by saline irrigation + epinephrine
*priapism is an emergency (irreversible ischemic changes may occur in the penile tissue if priapism is not corrected after 4 hours, resulting in fibrosis and erectile dysfunction)

Question 9

Newer sickle cell disease drugs

Answer 9

• oxbryta (voxelotor)

- crizanlizumab

Question 10

Voxelotor mechanism + formulation

Answer 10

• Increases the affinity between Hb and oxygen and inhibit sickling of red blood cells.
• oral

Question 11

crizanlizumab mechanism

Answer 11

Binds to P-selectin on the surface of platelets and endothelium in the blood vessels and has been shown to inhibit interactions between endothelial cells, platelets, red blood cells, sickled red blood cells, and leukocytes, causing a blockade and thereby preventing these cells from being

Question 12

hematuria in a patient with sickle cell disease think

Answer 12

renal papillary necrosis

Question 13

Greatest risk factor for mortality among SCD patients

Answer 13

pulmonary HTN (over 30% of adult SCD patients)

Question 14

Hydrea mechanism for SCD

Answer 14

• increases HbF

- produces nitric oxide, which helps with blood vessel relaxation

Question 15

leading cause of death among sickle cell disease patients

Answer 15

• acute chest syndrome

Question 16

Indications for exchange transfusion in SCD

Answer 16

• CVA
• respiratory failure
• multi-organ failure
• moderate to severe ACS

Question 17

Goal HbS level with exchange transfusion in SCD

Answer 17

below 30%

Question 18

Management of SCD patient with CVA after CVA

Answer 18

• Chronic transfusions to maintain HbS level of less than 30% (they are at significantly increased risk of recurrent CVA)

Question 19

Management of SCD patient undergoing surgery

Answer 19

• preoperative transfusion to maintain hgb above 10

Question 20

why meperidine has fallen out of favor

Answer 20

• increased seizure risk

Question 21

Management of sickle cell trait patient presenting with hematuria

Answer 21

• renal imaging to rule out stone, tumor, or infarction

- supportive care

Question 22

Goal HbF with hydroxyurea treatment

Answer 22

Greater than 20%

Question 23

Medications that have been shown to prevent CKD development in SCD patients

Answer 23

• hydrea

- ACE inhibitors

Question 24

Splenic sequestration crises clinical features

Answer 24

• acute drop in hgb + rapidly enlarging spleen
• spleen size commonly regresses after a blood transfusion (important feature because it differentiates splenic sequestration from hypersplenism)
• typically seen in infants or variant SCD syndromes because most SCD patients auto-infarct by adulthood
• medical emergency as large percentage of total blood volume can become sequestered in the spleen, leading to hypovolemic shock and death

Question 25

Management of splenic sequestration crises

Answer 25

• transfusion

- afterward need splenectomy to prevent recurrence

Question 26

crizanlizumab mechanism

Answer 26

binds to P-selectin and blocks its interaction with P-selectin glycoprotein ligand 1 (PSGL-1)

Question 27

Management of pulmonary HTN in SCD patients

Answer 27

• hydrea (reducing frequency of vaso-occlusive crises with hydrea can lead to a decrease in progression of pHTN)

Question 28

common cause of copper deficiency

Answer 28

high doses of OTC zinc (Competitive absorption)

Question 29

Endari generic name

Answer 29

L-glutamine

Question 30

endpoints for voxeletor

Answer 30

• decreased transfusions (prevents sickling and RBC destruction)
• increased hemoglobin response (1.0 g from baseline)

Question 31

Goal hgb S level with exchange transfusion

Answer 31

less than 30%

Question 32

Why is hgb A 0 in SCD?

Answer 32

Hgb A is composed of α2β2, and SCD is a point mutation in Beta, so electrophoresis doesn’t detect any hgb A

Question 33

W