Leukocyte Alkaline Phosphatase Stain (LAP)
Optimizing Laboratory Testing for Hematologic
The LAP assay is clearly a subjective test based on an inexact science. The procedure involves counting 100 neutrophils including lobed and band forms but excluding other left-shifted granulocytes, eosinophils, and basophils. The reaction is scored from 0 to 4 depending on the number of stained granules and the intensity of the stain. The number of cells is multiplied by the score and added up with a normal range being from 40 to 100.
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- Optimizing Laboratory Testing for Hematologic Disorders Series
- The Big Picture: We Need to Focus On...
- LAP: A Test That Time Has Passed By
- LAP: Assay History
- LAP: Original Clinical Utility
- LAP Procedure—an Inexact Science!
- Typical Staining Type Reaction
- Subjective Nature of the Scoring Process
- LAP Scoring Example
- LAP Discontinued at Mayo Clinic
- Low LAP Scores* Not Specific for CML: A Mayo 1-Year Experience
- Low LAP Scores* Do Not Indicate Myeloid Malignancy: A Mayo 1-Year Experience
- High LAP Scores* Not Specific for PV: A Mayo 1-Year Experience
- High LAP Scores* Do Not Indicate Myeloid Malignancy: A Mayo 1-Year Experience
- LAP: A Test Whose Time Has Passed
- Consequences of an Abnormal LAP
- Alternatives to LAP
- Alternatives to LAP: BCR/ABL
- Alternatives to LAP: JAK2