Which of the following indicates a low WBC count?

• A. Leukocytosis
• B. Leukopenia
• C. Thrombocytosis
• D. Neutrophilia

Answer: (B)

A low white blood cell (WBC) count is referred to as leukopenia. This condition signifies a decrease in the number of leukocytes present in the blood, which can lead to an increased risk of infections due to the body's compromised immune response.

In contrast, leukocytosis indicates an elevated WBC count, typically in response to infection, inflammation, or other conditions. Thrombocytosis refers to an increase in the number of platelets in the blood, which is unrelated to WBC counts. Neutrophilia represents an increase in neutrophils, a specific type of white blood cell, again highlighting a different condition than leukopenia. Thus, the term that specifically indicates a low WBC count is indeed leukopenia.