Reactive monocytosis can be seen in which condition?

Reactive monocytosis can be seen in which condition?

• A. rheumatoid arthritis
• B. tuberculosis
• C. infectious mononucleosis
• D. SLE

Answer: (B)

Reactive monocytosis reflects an increase in circulating monocytes in response to chronic inflammation or granulomatous infection. Tuberculosis drives a macrophage-dominated response with granuloma formation, so monocytes are mobilized and can rise in the blood as part of this process. In infectious mononucleosis, the hallmark is lymphocytosis with atypical lymphocytes, not monocytes. Autoimmune diseases like rheumatoid arthritis and SLE can cause various hematologic changes, but monocytosis is not a defining feature. Therefore, tuberculosis is the best fit for reactive monocytosis.

Reactive monocytosis reflects an increase in circulating monocytes in response to chronic inflammation or granulomatous infection. Tuberculosis drives a macrophage-dominated response with granuloma formation, so monocytes are mobilized and can rise in the blood as part of this process. In infectious mononucleosis, the hallmark is lymphocytosis with atypical lymphocytes, not monocytes. Autoimmune diseases like rheumatoid arthritis and SLE can cause various hematologic changes, but monocytosis is not a defining feature. Therefore, tuberculosis is the best fit for reactive monocytosis.