An increased number of bands in the peripheral blood indicate:

• A. Leukemia
• B. Left shift
• C. Neutropenia
• D. Autoimmune hemolytic anemia

Answer: (B)

An increased number of bands signals a left shift, which means the bone marrow is releasing immature neutrophils (band neutrophils) into the bloodstream to meet a surge in demand, usually from acute infection or inflammation. When the body detects trouble, cytokines stimulate granulopoiesis and push neutrophils out faster, so you see more bands alongside mature neutrophils. This is a sign the immune system is actively responding, particularly to bacteria or significant tissue injury.

Leukemia would involve abnormal white cell proliferation with blasts or other atypical cells, not just more bands. Neutropenia is a low neutrophil count, which is the opposite of what a left shift shows. Autoimmune hemolytic anemia involves destruction of red blood cells, not changes in neutrophil maturation.