A laboratory professional notes single azurophilic needlelike inclusions in the cytoplasm of many of the circulating blasts while reviewing a blood smear of an AML patient. What is the most probable identification of the inclusion?

Question

Quizplus · Accepted Answer

The azurophilic needlelike inclusions in the cytoplasm of many of the circulating blasts in the blood smear of this AML patient are most likely Auer rods. Auer rods are characteristic of AML and are formed from fused primary granules. They can be seen in the cytoplasm of myeloblasts, promyelocytes, and occasionally other myeloid cells. Toxic granulation, Döhle bodies, and uric acid crystals can also be seen in the cytoplasm of white blood cells, but they do not appear as azurophilic needlelike inclusions. Toxic granulation is characterized by heavy staining of primary granules that may obscure the nucleus. Döhle bodies are small, blue-gray inclusions in the cytoplasm that are caused by rough endoplasmic reticulum swelling. Uric acid crystals can be seen in the cytoplasm of white blood cells in patients with hyperuricemia.

A Laboratory Professional Notes Single Azurophilic Needlelike Inclusions in the Cytoplasm