Ordering Recommendation

Evaluate the cause of an isolated prolonged PTT in a patient who is not currently bleeding.

Mnemonic
PREKALL
Methodology

Electromagnetic Mechanical Clot Detection

Performed

Tue

Reported

1-8 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Lt. blue (sodium citrate). Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines.

Specimen Preparation

Transfer 2 mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 1 mL)

Storage/Transport Temperature

CRITICAL FROZEN. Separate samples must be submitted when multiple tests are ordered.

Unacceptable Conditions

Serum. EDTA plasma, clotted or hemolyzed specimens.

Remarks
Stability

Ambient: 4 hours; Refrigerated: Unacceptable; Frozen: 2 weeks

Reference Interval

55-207%

Interpretive Data



Compliance Category

Standard

Note
Hotline History
N/A
CPT Codes

85292

Components
Component Test Code* Component Chart Name LOINC
0099043 Prekallikrein (Fletcher) Assay 52759-8
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Fletcher Factor
Prekallikrein Factor, Activity