Test Overview
Test Methodology

Photo-optical clot determination with Factor VII deficient substrate.

Test Usage

Detection of specific coagulation factor VII deficiency.

Reference Range *

50-150%

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Increased in patients taking oral contraceptives. Interpretation of results may be limited if patient is receiving anticoagulant therapy.

Test Details
Days Set Up
Monday - Friday, one run per day
Analytic Time

1 hour

Soft Order Code
F7
MiChart Code
Factor 7 Assay
Synonyms
  • Factor VII Assay
  • Factor VII:C Assay
  • F7
  • Factor 7 Activity
  • Factor 7 Assay
Laboratory
Hematopathology
Section
Coagulation
Specimen Requirements
Collection Instructions

Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a plastic vial, and freeze the specimen within 4 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.

Rejection Criteria
Specimens will be rejected if not properly filled, clotted, grossly hemolyzed,contaminated with heparin,or refrigerated.
Blue Top Tube
Normal Volume
Full 2.7mL tube or 1mL plasma aliquot
Minimum Volume
Full 1.8mL tube or 1mL plasma aliquot
Storage Temperature
Room temperature for whole blood or frozen aliquot of citrated plasma.
Additional Information

Factor VII may be increased in patients with nephrotic syndrome and in burn patients and decreased in patients with vitamin K deficiency, factor VII deficiency, liver disease, warfarin therapy, and occasionally in patients with chronic renal failure. Normal levels of factor VII may be present in patients with congenital dysfibrinogenemia.

Billing
CPT Code
85230
Fee Code
31125
LOINC
3198-9
Resources