What is the characteristic cell type found in chronic lymphocytic leukemia (CLL)?

In chronic lymphocytic leukemia (CLL), the characteristic cell type is indeed smudge cells. Smudge cells are lymphocytes that have become fragmented during the process of blood smear preparation, and they are a hallmark feature seen under the microscope in patients with CLL. These cells result from the fragile nature of the neoplastic (cancerous) lymphocytes seen in CLL, making them easily break apart during the smear preparation.

The presence of smudge cells can help differentiate CLL from other blood disorders, as this phenomenon is less common in other types of leukemia. Although other cell types and markers may be associated with different leukemias or conditions, smudge cells specifically indicate the lymphocytic nature of CLL.

In contrast, Reed Sternberg cells are associated with Hodgkin lymphoma, Auer rods are indicative of acute myeloid leukemia (AML), and Bence Jones protein primarily relates to multiple myeloma. Each of these cell types corresponds to different hematological conditions and helps in making a correct diagnosis in their respective contexts.