Correct Answer:
B. Infection
An increase in leucocytes, also known as white blood cells (WBCs), in the bloodstream is medically termed leukocytosis. This condition most commonly indicates an infection or inflammation within the body. Leucocytes are vital components of the immune system, and their primary role is to fight off invading pathogens, such as bacteria, viruses, fungi, or parasites, and to help in the inflammatory response. When the body detects an infection, it ramps up the production and release of these immune cells from the bone marrow to effectively combat the threat. Different types of leucocytes may increase depending on the specific nature of the infection, providing clues for diagnosis.
- Anaemia refers to a condition characterized by a deficiency of red blood cells or hemoglobin, which is distinct from an increase in white blood cells.
- While an increase in leucocytes does represent an increased defense, 'Infection' is the underlying reason or stimulus for that defense mechanism to be upregulated, making it a more direct and precise indication. The body's defense increases *because of* an infection.
- Non formation RBC (Red Blood Cells) describes a problem related to red blood cell production, which could lead to anaemia, but it is not directly indicated by an increase in white blood cells.