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Test Details

Mnemonic

PT18Q

Ordering Code

3401179

CPT-4 Code(s)

84393

Specimen Information

Patient Preparation

Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.

Collect

Lavender EDTA

Specimen Preparation

Centrifuge, separate plasma from cells and send 1.0 mL plasma in a screw capped plastic vial.

Minimum Volume

0.5 mL

Transport Temperature

Refrigerated

Rejection Criteria

Hemolysis

Stability

Room temperature: 14 days
Refrigerated: 22 days
Frozen: 22 days

Methodology

Electrochemiluminescence (ECLIA)
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Reference Range

≤0.72 pg/mL
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Performing Laboratory

Quest
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New York DOH Approval Status

Yes
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