Sickle Cell Anemia

Genetic Pattern
- Autosomal recessive
- Homozygote inheritance of Hemoglobin S (HbS)
- Predominantly seen in the African American population
Oxygenated HbS does not dissolve well and forms a gel that distorts the shape of the RBC into a sickle.
- This makes the cells “sticky” and less flexible leading to clogging of small blood vessels.
- These cells are also fragile and frequently injured during normal circulation
Symptoms are due to vasoocclusion and hemolysis
There is an increased risk of crisis associated with dehydration, acidosis and hypoxemia
- Any sickle cell crisis may be life threatening
Sickle cell patients are at an increased risk of
- Functional splenectomy
  - Leading to an increased risk of pneumococcal and salmonella infection.
- Non healing ulcers
- Strokes
- Retinopathies
- Osteomyelitis
Life expectancy is > 50 years
- Chronic multisystem disease with death from organ failure

Childhood on may present with vascular occlusion causing severe pain which lasts hours to days
Events secondary to infarct and ischemia
- Avascular necrosis of the femoral head
- Hematuria
Hepatosplenomegaly
Systolic ejection murmur may be heard
Cardiomegaly may be found
Skin ulcers may be present

CBC
- Elevated white count
- Decreased hemoglobin
- Possible thrombocytosis
- Elevated retic count
Peripheral smear
- Sickled cells
- Nucleated RBCs – extremely immature RBCs, only seen with severe anemia
- Howell-Jolly bodies
- Target cells
Elevated indirect bilirubin
DNA testing
Definitive diagnosis is made with electrophoresis.

Folic acid supplement
Pneumococcal vaccination
Early broad spectrum antibiotics to prevent serious bacterial infection
Acute painful episode
- Fluids
- Pain medication
- Oxygen
- Exchange transfusion

G6PD Deficiency Anemia

Mutation causing a defective glucose-6-phosphate dehydrogenase enzyme. The specific mutation dictates the severity of the disease.
G6PD enzyme is a key factor in the only pathway that creates reduced glutathione in an RBC. Reduced glutathione is responsible for cleaning up free radicals within an RBC.
During states of oxidative stress these patients are at an increased risk for hemolysis.
- Food – Fava Beans
- Medications
  - Antimalarial drugs
  - Sulfonamides
  - Methylene blue
  - Aspirin
- Stress from infection
  - Viral
  - Bacterial
X-linked recessive
- More common in men, but woman may be affected
Found in African, Medateranian, Asian and Middle Eastern populations
Most commonly affects black males

During an episode retic count and indirect bilirubin will be elevated
Peripheral smear
- Bite cells
  - As hemoglobin oxidizes and creates Heinz bodies the cell margins are deformed
- Heinz bodies
G6PD assay
- During an acute phase G6PD will not be low due to the increased retic count. This test may give a false negative until the acute phase has passed.

Prevention is key
Episodes are self limited so treatment is supportive
- Fluids
- Blood transfusion
- Dialysis