Which CBC finding is least likely in a patient with infection?

Which CBC finding is least likely in a patient with infection?

• A. Neutrophilia
• B. Leukocytosis
• C. Narrow buffy coat
• D. A left shift

Answer: (C)

Infection typically triggers an increase in white blood cells as the body fights the invader. This shows up as leukocytosis and often neutrophilia, with a left shift indicating release of immature neutrophils. The buffy coat—the white cell and platelet layer after centrifugation—gets thicker when there are more white cells. So, you’d expect a wider buffy coat in infection. A narrow buffy coat suggests a low white blood cell count, which isn’t characteristic of most infectious processes (though certain infections or severe illness can sometimes cause leukopenia). Therefore, a narrow buffy coat is the least likely CBC finding in infection.

Infection typically triggers an increase in white blood cells as the body fights the invader. This shows up as leukocytosis and often neutrophilia, with a left shift indicating release of immature neutrophils. The buffy coat—the white cell and platelet layer after centrifugation—gets thicker when there are more white cells. So, you’d expect a wider buffy coat in infection. A narrow buffy coat suggests a low white blood cell count, which isn’t characteristic of most infectious processes (though certain infections or severe illness can sometimes cause leukopenia). Therefore, a narrow buffy coat is the least likely CBC finding in infection.