Which of the following statements is true regarding aplastic crisis and its cause in sickle cell disease?

Aplastic crisis in sickle cell disease is characterized by a significant drop in hemoglobin levels and a decrease in the reticulocyte count due to the bone marrow's inability to produce new red blood cells. The true statement regarding aplastic crisis is that it is commonly caused by parvovirus B19 infection.

Parvovirus B19 specifically infects and destroys erythroid progenitor cells in the bone marrow, which are responsible for red blood cell production. This is particularly problematic in individuals with sickle cell disease, who already have compromised erythropoiesis due to their underlying condition. When the infection occurs, it can lead to a rapid decline in hemoglobin levels, resulting in the clinical presentation of aplastic crisis.

Other potential causes mentioned, like splenic sequestration and genetic predisposition, do not directly relate to the mechanism of an aplastic crisis specifically triggered by parvovirus B19. Sickle cell disease can lead to splenic sequestration, but this is a different complication characterized by splenic enlargement and acute anemia due to trapped sickled cells, not a pure aplastic crisis. Similarly, while sickle cell disease has a genetic basis, it does not directly cause an aplastic crisis, which is more about the acute