Leukocyte Alkaline Phosphatase.




Test Mnemonic

LAPSN

CPT Codes

  • 85540 - QTY (1)

Aliases

  • LAP Stain

Performing Laboratory

ARUP


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
5 mLWhole bloodSodium or Lithium heparin (Green) AmbientProtect both smears and whole blood from light. Package carefully to avoid breakage. Collect 5 mL whole blood and make 6 unfixed, well-prepared smears. Send both whole blood and 6 smears. Collect Monday - Wednesday only. Whole blood must be received within 24 hours of collection; smears must be made within 24 hours of collection and received within 7 days of collection. Deliver to Cleveland Clinic Laboratories ASAP on the same day of collection.

Minimum Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
1 mL    Whole blood
Six    Smears

Stability

Environmental Condition Description
AmbientBlood: 24 hours; Unfixed smears: 1 week
RefrigeratedBlood: Unacceptable; Unfixed smears: Unacceptable
FrozenBlood: Unacceptable; Unfixed smears: Unacceptable

Days Performed

Mon - Fri

Turnaround Time

2 - 6 days

Methodology

Name Description
Stain 

Reference Range

Special Info

Specimens collected in EDTA or specimens that have been spun will be rejected. Poorly prepared smears (e.g., too thick or no feather edge), broken or fixed smears are unacceptable. Smears made from anything other than heparin, smears made from blood older than 24 hours, and smears not protected from light are unacceptable. Whole blood not protected from light will be rejected. This test is New York DOH approved.

Clinical Info

Aids in differential diagnosis of neutrophilia, including chronic myeloid leukemia (CML) and leukemoid reaction.