Harlequin cells are a type of dysplastic eosinophil, which are white blood cells that contain both eosinophilic and basophilic granules in their cytoplasm. They are often called "hybrid eosinophilic basophilic precursors" due to their unique characteristic of harboring both types of granules.
These cells are commonly observed in acute myeloid leukemia (AML) with inv(16) and are often referred to as "harlequin cells" due to their distinctive appearance.
Here are some key characteristics of Harlequin cells:
- Dysplastic eosinophils: These are eosinophils that have abnormal characteristics, including the presence of both eosinophilic and basophilic granules.
- Metachromatic granules: These granules are stained by dyes in a different color than expected, often appearing purple-violet.
- Commonly observed in AML with inv(16): Harlequin cells are often found in patients with a specific type of acute myeloid leukemia that involves an inversion on chromosome 16.
The presence of Harlequin cells can be a valuable diagnostic tool for hematologists, helping them identify specific types of leukemia and guide treatment strategies.
