In patients with sickle cell disease, what is the typical level of Hemoglobin A?

• A. Increased
• B. Normal
• C. Decreased
• D. Variable

Answer: (C)

In patients with sickle cell disease, the typical level of Hemoglobin A is decreased. Sickle cell disease is a genetic disorder caused by a mutation in the gene that encodes the beta chain of hemoglobin, resulting in the production of Hemoglobin S (HbS) instead of the normal Hemoglobin A (HbA).

As a result, individuals with sickle cell disease primarily produce HbS, leading to a lower concentration of HbA. In these patients, the presence of HbA can vary based on factors such as the degree of co-inheritance of other hemoglobinopathies like hereditary persistence of fetal hemoglobin which can influence the overall hemoglobin profile. However, in the classical presentation of sickle cell disease, the level of Hemoglobin A is notably decreased, typically ranging from 0-20% depending on the individual's specific genetic makeup and any therapeutic interventions they might be receiving.