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Contact Factor Evaluation Profile (Esoterix)

CPT 85270; 85280; 85292; 85293

Test Details

Methodology

See individual tests.

Result Turnaround Time

3 - 7 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Related Documents

For more information, please view the literature below.

Procedures for Hemostasis and Thrombosis: A Clinical Test Compendium

Test Includes

Factor XI activity; factor XII activity; high molecular weight kininogen (Fitzgerald factor); prekallikrein (Fletcher factor)

Footnotes

1. Adcock DM, Kressin DC, Marlar RA. Effect of 3.2% vs 3.8% sodium citrate concentration on routine coagulation testing. Am J Clin Pathol. 1997 Jan; 107(1):105-110. 8980376
2. Reneke J, Etzell J, Leslie S, Ng VL, Gottfried EL. Prolonged prothrombin time and activated partial thromboplastin time due to underfilled specimen tubes with 109 mmol/L (3.2%) citrate anticoagulant. Am J Clin Pathol. 1998 Jun; 109(6):754-757. 9620035
3. National Committee for Clinical Laboratory Standardization. Collection, Transport, and Processing of Blood Specimens for Coagulation Testing and General Performance of Coagulation Assays; Approved Guideline. 5th ed. Villanova, Pa: NCCLS; 2008. Document H21-A5:28(5).
4. Gottfried EL, Adachi MM. Prothrombin time and activated partial thromboplastin time can be performed on the first tube. Am J Clin Pathol. 1997 Jun; 107(6):681-683. 9169665
5. McGlasson DL, More L, Best HA, Norris WL, Doe RH, Ray H. Drawing specimens for coagulation testing: Is a second tube necessary? Clin Lab Sci. 1999 May-Jun; 12(3):137-139. 10539100

Specimen Requirements

Specimen

Plasma, frozen

Volume

4 mL (2 mL in each of two tubes)

Container

Blue-top (sodium citrate) tube

Collection Instructions

Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.1 Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio.2,3 The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples, except when using a winged blood collection device (ie, "butterfly"), in which case a discard tube should be used.4,5 When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternate anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes. Centrifuge and carefully remove the plasma using a plastic transfer pipette, being careful not to disturb the cells. Transfer the plasma into a Labcorp PP transpak frozen purple tube with screw cap (Labcorp No. 49482). Freeze immediately and maintain frozen until tested. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.

Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume.

Storage Instructions

Freeze.

Patient Preparation

Do not draw from an arm with a heparin lock or heparinized catheter.

Causes for Rejection

Severe hemolysis; improper labeling; clotted specimen; specimen diluted with IV fluids; samples thawed in transit; improper sample type; sample out of stability.

LOINC® Map

Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
500436 Contact Factor Evaluation 500674 Factor XI Activity % 3226-8
500436 Contact Factor Evaluation 500367 Factor XII Activity % 3232-6
500436 Contact Factor Evaluation 500195 Prekallikrein Assay % 52759-8
500436 Contact Factor Evaluation 500461 Kininogen Activity % 52754-9
Order Code500436
Order Code NameContact Factor Evaluation
Order Loinc
Result Code500674
Result Code NameFactor XI Activity
UofM%
Result LOINC3226-8
Order Code500436
Order Code NameContact Factor Evaluation
Order Loinc
Result Code500367
Result Code NameFactor XII Activity
UofM%
Result LOINC3232-6
Order Code500436
Order Code NameContact Factor Evaluation
Order Loinc
Result Code500195
Result Code NamePrekallikrein Assay
UofM%
Result LOINC52759-8
Order Code500436
Order Code NameContact Factor Evaluation
Order Loinc
Result Code500461
Result Code NameKininogen Activity
UofM%
Result LOINC52754-9