What laboratory finding distinguishes leukemoid reaction from CML?

Question

Quizplus · Accepted Answer

The main laboratory finding that distinguishes leukemoid reaction from CML is the level of leukocyte alkaline phosphatase (LAP). LAP is usually low in CML and increased in leukemoid reaction. Other differences between the two conditions include the presence of Philadelphia chromosome or BCR-ABL fusion gene, which is usually present in CML but absent in leukemoid reaction, and the presence of basophilia and eosinophilia, which are more common in CML. Platelet counts can be normal or abnormal in both conditions, and the presence of blasts or micromegakaryocytes is more suggestive of CML.

What Laboratory Finding Distinguishes Leukemoid Reaction from CML