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Test Code
HNK1
Test Name
HNK1 (CD57) Panel
CPT Codes
86356, 86357
Included Tests
  • % CD8-/CD57+ Lymphs
  • Abs.CD8-CD57+ Lymphs
  • WBC
  • RBC
  • Hemoglobin
  • Hematocrit
  • MCV
  • MCH
  • MCHC
  • RDW
  • Platelets
  • Neutrophils
  • Lymphs
  • Monocytes
  • Eos
  • Basos
  • Immature Cells
  • Neutrophils (Absolute)
  • Lymphs (Absolute)
  • Monocytes(Absolute)
  • Eos (Absolute)
  • Baso (Absolute)
  • Immature Granulocytes
  • Immature Grans (Abs)
  • NRBC

Reflexes

  • Bands
  • Metamyelocytes
  • Myelocytes
  • Promyelocytes
  • Blasts/blast like cells
  • Megakaryocytes
  • Other, Lineage Uncertain
Expected Turnaround Time
1 - 3 days
Clinical Utility

This test monitors the CD57 lymphocyte subset in patients with chronic Lyme Disease.
Specimen and Container Info

Specimen Type: Whole Blood

Collection Container: Pale Yellow Top (Solution A or B) AND Lavender Top (EDTA)

Desired Specimen Volume: 8 mL (Pale Yellow) AND 3 mL (Lavender)
Collection Instructions
  1. Collect a pale-yellow top (ACD Solution A or B) tube AND collect a lavender top (EDTA) tube via venipuncture
  2. Fill tubes to capacity.
  3. Invert tube 8 to 10 times immediately after collection.
Processing and Submission Instructions
  1. Transport 8 mL of whole blood in the pale-yellow top AND 3 mL of whole blood in the lavender top (EDTA).
  2. Label specimens with room temperature stickers.
  3. This is a short stability test. Samples must arrive at the lab by 16:00 on the same day of collection.
Transport Instructions

Transport to the laboratory at room temperature.
Stability Requirements

Room Temperature

Lavender EDTA: 24 hours

ACD Yellow: 48 hours
Methodology
Flow Cytometry
Reference Intervals

See patient report.
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Varies
Reflex Tests
IMCEL
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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