Days Set Up
Tuesday and Friday, one run per day
Analytic Time

1 hour

MiChart Code
Chromogenic Factor 8
Soft Order Code
CHF8

Test Updated:

Synonyms

CHF8
Factor 8 Chromogenic Activity
Factor 8 Chromogenic
Factor 8 Activity, Chromogenic
Chromogenic Factor VIII Activity
Factor 8 Chromogenic
Chromogenic Factor 8 Activity

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Test Overview

Test Methodology

Chromogenic Substrate Assay

Test Usage

Monitoring Factor 8 replacement therapy in patients with Hemophilia A. Because this assay utilizes bovine reagents, this test cannot be used to assay emicizumab.

Reference Range

50 - 150%

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

Specimen Requirements

Collection Instructions

Collect specimen in 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, and aliquot plasma into a polypropylene 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 5mL of saline and the first 5mL of blood or six dead space volumes of the VAD discarded.

Blue Top Tube
Normal Volume
Full 2.7 mL tube or 1 mL plasma aliquot
Minimum Volume
Full 1.8 mL tube or 1 mL plasma aliquot

Billing Information

CPT Code
85240
Pro Fee Code
 
Insurance Auth Info
 
LOINC
3210-2

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.