Which laboratory finding is suggestive of splenic dysfunction?

Howell-Jolly bodies are remnants of nuclear material that are normally removed from red blood cells by the spleen during the process of erythrocyte maturation and clearance. When there is splenic dysfunction or when the spleen is absent, these nuclear fragments are not effectively removed, leading to their presence in the circulation. Therefore, the detection of Howell-Jolly bodies in a blood smear is indicative of impaired splenic function, often seen in conditions such as splenectomy, sickle cell disease, or other disorders affecting splenic health and activity.

In contrast, target cells are associated with conditions like liver disease or hemoglobinopathies but do not specifically indicate splenic dysfunction. Microcytic and macrocytic red blood cells suggest other types of anemia and deficiencies, such as iron deficiency anemia or vitamin B12 deficiency respectively, but they do not correlate specifically with splenic activity. Thus, Howell-Jolly bodies serve as a classic marker for identifying issues related to the spleen's ability to filter and clear abnormal red blood cells.