What condition can result in leukopenia?

Leukopenia refers to a reduced white blood cell (WBC) count, which can impair the body’s ability to fight infections and respond to inflammation. Bone marrow failure is a primary cause of leukopenia, as the bone marrow is responsible for producing blood cells, including leukocytes. Conditions that affect the bone marrow, such as aplastic anemia, certain cancers, or the effects of chemotherapy, can lead to a diminished production of white blood cells, resulting in leukopenia.

The other options do not contribute directly to a decrease in white blood cell count: infections may cause leukocytosis due to an increase in WBC in response to the infection, dehydration can cause hemoconcentration but typically does not affect the absolute number of white blood cells, and thrombocytosis relates to an increase in platelets, which does not directly influence leukocyte levels. Therefore, bone marrow failure is the most pertinent condition associated with leukopenia.