Exam 2, deck 2 Flashcards
Ratio of Sickle cell trait
1:12 Black Americans
1:150 Hispanic Americans
300,000 babies born each yr with Sickle cell disease globally
2,000 babies with SCD born in US
SCD has a problem on what chromosome. What happens?
Chromosome 11
Point mutation for Hemoglobin S
Substitutes Glutamine for Valine
SCD is autosomal _____
Recessive
must have 2 abnormal copies to result in disease
Hemoglobin Genotypes for SCD
AA: Normal hemoglobin
AS: Sickle cell trait
SS: Sick cell disease
Other beta globin Traits
C trait (AC)
B0 trait (AB0)
B+ trait (AB+)
You have a mom and dad who both have Sickle Cell trait what are your genetic possibilities?
Genetic possibilities for mom with Beta Thalassemia trait (AB) and dad with Sickle cell trait (AS)
Genetic possibilities for mom with hemoglobin C trait (AC) and dad with Sickle cell trait (AS)
labs that show intravascular and extravascular hemolysis in SCD
Increased LDH
Increased bilirubin
Sickle RBC lives how long vs normal
8-21 days vs 120 days
polymerization of hemoglobin S leading to membrane rigidity
SCD
What type of anemia is seen in SCD
Normocytic anemia
what type of anemia is seen in SB and SC
microcytic anemia
target cells on smear
Hemoglobin SC
general preventative care for SS and SB0
Penicillin by 6 weeks of age
(spleen is impacted and not as effective to prevent infection - functional asplenia)
<3 years - 125 mg BID
>=3 years - 250 mg BID
Transcranial Doppler Ultrasound (TCD) by age 2 and at least annually until unable to obtain values - looking at cerebral blood flow to see who is at high risk for stroke
All types of sickle cell genotypes preventative care
Fever precautions: 101 is a med emergency
pneumococcal and meningococcal vaccines
annual influenza vaccine
Annual retinopathy screening starts at 10 years
annual screening for proteinuria begins at age 10 yrs
Genetic counseling for parents and adolescents
Folic acid supplementation if live outside US
most common cause of death in children with SCD
infection
SCD is at higher risk for what infections
pneumonia
Osteomyelitis which can be difficult to discern from Vaso-occlusive pain (VOP) on imaging
most common complication in SCD
Vaso-occlusive pain crisis
Pain in a vaso-occlusive pain crisis is what type of pain
Ischemic due to tissue infarction
Vaso-occlusive pain crisis may be precipitated by
dehydration
temp extremes
A pulmonary emboli in SCD is from
bone marrow breaking off
Defined as a new lung infiltrate, chest pain or resp sx +/- fever
Acute chest syndrome
Any fever in sickle cell disease requires
blood cultures
antibiotics
+/- chest x ray
vascular flow out of spleen blocked due to occlusion. Spleen starts blowing up like a balloon
splenic sequestration