Final answer:
Leukopenia is the correct diagnosis for a blood sample with a decreased number of normal WBCs. It indicates a below-normal production of leukocytes, which could lead to an increased risk of infection. Leukocytosis, Neutropenia, and Lymphocytosis are related conditions but do not describe a decrease in normal WBCs.
Step-by-step explanation:
If a blood sample has a decreased number of normal white blood cells (WBCs), the correct diagnosis is B) Leukopenia. Leukopenia is the condition characterized by the below-normal production of leukocytes (white blood cells), and it can be a critical condition because it may render an individual unable to effectively ward off diseases. Leukocytosis, on the other hand, refers to excessive leukocyte proliferation, which can also be problematic as the leukocytes may be nonfunctional and leave the individual vulnerable to infections. Neutropenia is a form of leukopenia that specifically relates to a decrease in neutrophils, which are a type of white blood cell that fights infection. Lymphocytosis is an increase in lymphocyte counts, which might be due to viral infections or some cancers.
For example, a patient undergoing chemotherapy might have their white blood cells, specifically neutrophils, destroyed by the treatment, leading to neutropenia. Neutrophils are a type of granular leukocyte important in fighting bacterial infections. Therefore, healthcare providers monitor blood cell counts closely before proceeding with such treatments.