Review Question - QID 104651

Patients with sickle cell anemia are often treated with hydroxyurea. This has the effect of increasing the HgbF in circulation.

Hydroxyurea increases the amount of HgbF in circulation while raising the amount of total hemoglobin in the body. The result is that HgbS has less of a chance of pairing with each other and resulting in a sickled red blood cell leading to a sickle cell crisis. Hydroxyurea is often used to reduce the length and number of sickle cell crises in patients with severe disease. It should be noted that hydroxyurea has no role in the management of an acute sickle cell crisis episode, but is often continued during acute crises given its role in chronic management.

Mehta et al. discusses the management of patients with sickle cell anemia. They state that hydroxyurea can be used to decrease the frequency of painful episodes and associated comorbidities.

Mulaku et al. performed a literature review attempting to better understand the efficacy of using hydroxyurea to treat pediatric patients with sickle cell anemia. They found that evidence is currently lacking to determine whether hydroxyurea improves survival in young children. They do, however, advocate for its use in situations where patients can be monitored appropriately.

Illustration A: This is a blood smear of a patient with sickle cell anemia. Note the sickled red blood cells.

Incorrect Answers:
Answer 1,2: Hydroxyurea does not directly effect the oxygen carrying capacity of native hemoglobin.
Answer 4: Hydroxyurea does not affect the levels of HgbS.
Answer 5: Hydroxyurea increases the concentration of fetal hemoglobin.