Sickle Cell

Question 1

Comprehensive Clinics

Answer 1

Nurses, NPs, doctors, social workers, counselors

Question 2

Sickle Cell Disease Pathophys

Answer 2

substitution of valine for glutamic acid at 6th AA position on hemoglobin

• formation of polymers when hemoglobin becomes deoxygenated
• deformed (sickled) RBCs –> block blood flow in microvasculature –> local tissue hypoxia, pain, tissue damage
• hemolysis –> chronic anemia

Question 3

Sickle cell traits

Answer 3

FA - normal
FS - both alleles are S –> sickle cell disease
FSC - one allele S, one allele C –> sickle cell disease
FAS - carrier of sickle cell
FSA - beta-thalassemia

Question 4

Common procedures for SCD kids

Answer 4

1. Tonsillectomy - lymphoidal tissue hypertrophy –> obstructive sleep apnea
2. Cholecystectomy - bilirubin gallstones from hemolytic anemia

Question 5

Risk of sepsis in kids with SCD

Answer 5

infants and kids with SCD at greater risk of sepsis

• decreased splenic function -> encapsulated organisms (s. pneumo, Hib, N. meningitidis)
• prophylactic penicillin greatly decreases risk (stop around 5-6 y.o)

Question 6

Goals for comprehensive SCD appointment

Answer 6

1. How is family doing/dealing with disease?
2. Frequency of painful/vaso-occlusive episodes?
3. Frequency of fevers?
4. Access to healthcare?

Question 7

Expected complications of SCD

Answer 7

1. Jaundice - hemolysis of RBCs
2. Anemia - can be result of recent infection, hypersplenism
3. Stroke - increased risk (evaluate with doppler)
4. Respiratory problems - lungs frequent site for sickling, vaso-occlusion of lung parenchyma –> acute chest syndrome (EMERGENCY = oxygen supplementation and transfusion)

Question 8

Immunizations for SCD patients

Answer 8

Hib vaccine
Pneumococcal vaccine
Meningococcal vaccine
Influenza vaccine

Question 9

Inheritance of SCD

Answer 9

Autosomal recessive - each parent must have 1 allele

- knowing newborn screen is important to know whether or not to start prophylactic penicillin

Question 10

Prenatal testing for SCD

Answer 10

Can do it, some testing in development

• samples of blood obtained in utero
• extracting DNA from chorionic villi

Question 11

Effects of chronic illness on growth and development

Answer 11

• can affect academic progress

- socialization and self-esteem

Question 12

Growth in SCD

Answer 12

• impairment of growth in SCD is common
• chronic anemia
• poor nutrition
• painful crises
• endorine dysfunction

Question 13

Important PE for SCD

Answer 13

1. Splenic Enlargement - common in first 2 years of life (make sure it isn’t massive)
2. Sclera - jaundice from RBC hemolysis
3. Neuro exam - evaluate for potential stroke

Question 14

Baseline CBC in SCD

Answer 14

common to have baseline Hgb from 6-9 range

- lower the baseline = lower threshold for acute changes

Question 15

When to seek care with SCD

Answer 15

FEVER - emergency
Splenic enlargement 
Slurred Speech - stroke
Chest pain - EMERGENCY
Rapid breathing - EMERGENCY
Pallor and jaundice
Priapism - permanent damage possible

Question 16

Aplastic crisis

Answer 16

temporary inhibition of erythroid production caused by viral illness (parvovirus)

Question 17

Acute Chest Syndrome

Answer 17

child with SCD presenting with fever, cough, difficulty breathing, low sats, chest pain
- PNA, fat embolism, intrapulmonary sickling

Question 18

DDx for chest pain, tachypnea and fever in SCD

Answer 18

1. Acute Chest Syndrome
2. Pericarditis
3. CHF
4. Rib infarction - vaso-occlusive crisis
5. Sepsis

Question 19

Acute Chest Syndrome CXR

Answer 19

bilateral lung infiltrates
atelectasis - pain can exacerbate this by not taking good breaths
cardiomegaly - from baseline in SCD
possible effusions

Question 20

CBC findings is stress response in SCD

Answer 20

SCD patients frequently show exaggerated leukocytosis and thrombocytosis
- don’t definitively help diagnose sepsis or ACS

Question 21

Treatment for pain crises

Answer 21

IV fluids (vigorously rehydrate as it can contribute to sickling), NSAIDs, narcotics (remember they are a respiratory depressant --> further exacerbate atelectasis)
- possible PCA

Question 22

Atelectasis

Answer 22

partially collapsed lung due to obstruction

• serious risk for kids with ACS
• critical to do deep breathing and assist devices (incentive spirometer)

Question 23

RBC transfusion for ACS

Answer 23

only way to directly reduce # of sickling RBCs
*exchange transfusion - best wat
Use if: fall in Hgb below baseline, increased RR, worsening chest symptoms, declining O2 sats, infiltrates on CXR

Question 24

ABx in acute chest syndrome

Answer 24

Broad IV Abx started
- Viruses, Chlamydia, Mycoplasma, Bacteria
3rd generation ceph + macrolide