Ordering Recommendation

Evaluate the cause of an isolated prolonged partial thromboplastin time (PTT) in a patient who is not currently bleeding.

Mnemonic

F12

Methodology

Electromagnetic Mechanical Clot Detection

Performed

Mon-Sat

Reported

1-3 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 specimens 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

58-166%

Interpretive Data



Compliance Category

Standard

Note

Hotline History

N/A

CPT Codes

85280

Components

Component Test Code* Component Chart Name LOINC
0030115 Factor XII, Activity 3232-6
* 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

  • Coagulation Factor XII Activity Assay, Plasma
  • Factor X11a
  • Hageman factor
  • Hageman Factor (Contact Factor)
  • Intrinsic Factor Proteins
  • Intrinsic Factors
  • Surface Factor
Factor XII, Activity