Which of the following results indicates effective therapy with filgrastim?

Filgrastim is a medication that stimulates the production of neutrophils, a type of white blood cell that plays a critical role in the immune response. It is primarily used in patients who are at risk for neutropenia, particularly those undergoing chemotherapy or those with certain bone marrow disorders. Effective therapy with filgrastim would be indicated by an increased neutrophil count, as this demonstrates that the drug is functioning as intended to boost the immune system's ability to fight infections.

While increased platelet counts and hemoglobin levels are important in assessing overall blood health, they are not directly influenced by filgrastim since its primary effect is on the neutrophil lineage of the blood cells. Similarly, increased erythropoietin levels are related to red blood cell production and not directly affected by filgrastim. Therefore, the increase in neutrophils specifically indicates that the therapy with filgrastim is effective in addressing the target condition.