Medical Laboratory Scientist (MLS) ASCP Practice Exam

Howell-Jolly bodies are small, round, purple-staining inclusions found within red blood cells, which are remnants of nuclear material. Their presence is typically associated with the condition of splenectomy, which is the surgical removal of the spleen. The spleen plays an essential role in filtering blood and removing abnormal cells and cellular debris, including damaged red blood cells that may contain residual nuclear material.

In individuals who have undergone splenectomy, the lack of splenic function results in the accumulation of these unfiltered red blood cells, leading to an increased prevalence of Howell-Jolly bodies in the bloodstream. This indicates that the body is unable to properly clear out these remnants without the action of a functioning spleen.

In conditions such as thalassemia, iron deficiency anemia, and myelodysplastic syndrome, although abnormalities in red blood cells may occur, Howell-Jolly bodies are not characteristic findings. These conditions may feature other types of inclusions or changes in red blood cell morphology, but they do not directly relate to the lack of removal of nuclear remnants as seen in splenectomy. Therefore, the observation of Howell-Jolly bodies serves as an important diagnostic clue pointing to a history of splenic removal or dysfunction.