Sickle Cell Disease Edited Flashcards
Key Vaccines in SCD
Routine Childhood series 2
- H Flu Type B (Hib)
- Pneumo conjugated (PCV13 Prevnar)
Additional Vaccines Due to Functional Asplenia
4 speciifc timing
- Meningococcal conjugate series + routine boosters
- Meno Serogroup B (Bexsero, Trumenda) at age 10 and over
- Pneumo (PPSV23-Pneumovax) at age 2, booster 5 yeasr later AND at age 65 or over
- Pneumo (PCV13-Prevnar) x 1 in any pt >= 6 years of age if not given in childhood series
SCD most commonly effects what population?
African Americans
How long does it take for symptoms of SCD to develop and why?
2-3 months after birth and fetal Hgb (HgbF) blocks sickling of RBCs
What are the two types of Acute Sickle cell crisis and what is the cause?
Vasoocclusive crisis (acute pain crisis): caused by vascular occlusion preventing oxygen from reaching the tissues (sickle RBCs don’t transport oxygen effectively and stick together-blocking smaller blood vessels)
- most common in lower back, hips, legs, abdomen, and chest
- can last days or weeks
Acute chest syndrome: pain is in chest and evidence of pulmonary infection
- life-threatening
- leading cause of death in SCD
Common chronic complication of SCD?
- Pulmonary HTN
- chronic pain
- avascular necrosis (bone death)
- renal impairment
SCD causes what issue?
- Inherited RBC disorder resulting from genetic mutation in Hgb genes
- homozygous inherited sickle cell genes=RBCs with abnormal Hgb (HgbS)
- RBCs have concave “sickle” shape instead of doughnut shaped without the hole
- Sickled RBCs hemolyze after 10-20 days
- leads to anemia
- most common in african americans
Non drug treatment for SCD? 2
- Blood transfusion
- provides RBCs with HgbA (normal)
- protects against life-threatening complications of SCD
- stroke, acute chest syndrome, and severe anemia warrant transfusion
- goal Hgb no higher than 10 g/dL post infusion
- Bone marrow transplant
- only cure for SCD
- high risk and costly so not widely used
Drug tx for SCD? 6
- Immunizations reduce infection risk
- Abx reduce infection risk
- Analgesics for pain
- Hydroxyurea prevent/reduce acute & chronic complication
- L-Glutamine prevent/reduce acute & chronic complication
- Chelation therapy to reduce iron overload from tranfusion
Sepsis and mengingitis can occur in SCD due to what 3 main pathogens?
- S. Pneumo
- H. Influenzae
- N. Mengingitiis
and salmonella
Infections are major cause of death especially in children under 5
- sepsis & meningitis can occur
- risk of atypical infections is increased
- vaccines are essential to prevent infection
What should be used in children that screen + for SCD at birth
- prophylactic penicillin BID from birth-age 5
- to prevent risk of death from invasive pneumo infection
- if spleen is removed surgically or pt gets pneumo infection despite prophylaxis-penicillin should be continued indefinitely
Sickle Cell pain management
mild-moderate pain
- often managed @ home
- rest, fluids, warm compress to affected area
- NSAIDs or acetaminophen
severe pain or vascular occlusive crisis (VOC)
- guided by pt reported pain severity
- review patients outpatient analgesic use and initiate treatment plan within 30 minutes
- IV opioid or patient controlled analgesia (PCA) will be required
What is hydroxyurea and what does it do?
- Disease modifying agent that stimulates the production of HgbF
- reduces frequency of acute pain crises, acute chest syndrome, and need for blood transfusion
When is Hydroxyurea indicated? In SCD
- Adults who have 3 or more acute pain crisis in 1 year
- should be considered in all children over 9 months old regardless of disease severity
How is hydroxyurea taken?
Oral capsule
Hydroxyurea brand names
droxea
hydrea
siklos
Boxed warning for hydroxyurea?
Myelosuppression (decreased WBCs and platelets
malignancy (leukemia, skin cancer)
2 warnings for hydroxyurea?
- Fetal embryo toxicity
- Avoid live vaccines
How do you know if hydroxyurea is at toxic levels? 2 labs
ANC<2,000/mm3
Platelet <80,000/mm3
IF TOXICITY OCCURS, HOLD UNTIL BONE MARROW RECOVERS AND RESTART DOSE@ -5MG/KG/DAY
What should be monitored for hydroxyurea?
CBC WITH DIFFERENTIAL q2-4 wks until stable then 2-3 months
What is required for hydroxyurea?
Contraception during treatment and
female: 6 months after
male: 12 months after
!! Hazard agent-wear gloves when dispensing and wash hands before and after
What supplementation is used for hydroxyurea?
FOlic acid for macrocytosis
What type of agent is hydroxyurea?
Hazardous
Wear disposable gloves to limit exposure dont open the capsule
wash hands before and after handling
What drug interactions for hydroxyurea?
- Drugs that cause myelosuppression
- clozapine, deferiprone, leflunomide, natalizumab, tofacitinib
- -Limus
- pimecrolimus, tacrolimus (topical)
- Antiretrovials
- didanosine, stavudine
