Test Catalog

Test Id : CHF8

Chromogenic Factor VIII Activity Assay, Plasma

Useful For
Suggests clinical disorders or settings where the test may be helpful

Monitoring coagulation factor replacement therapy of selected extended half-life coagulation factor replacements

 

Aiding in the diagnosis of hemophilia A using a 2-stage assay, especially when the 1-stage assay was normal

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This assay is indicated in situations where there is a clinical suspicion of hemophilia A diagnosis, but the 1-stage Factor VIII (FVIII) assay is normal. However, recent guidelines also recommend this assay be performed in addition to the 1-stage assay in the initial workup of hemophilia A.

 

Testing for autoantibodies to FVIII in the presence of a low FVIII activity may be clinically indicated. For adding on FVIII inhibitor, call 800-533-1710 within 7 days to assess if adequate plasma sample is available.

 

See Hemophilia Testing Algorithm in Special Instructions.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Name
A short description of the method used to perform the test

Chromogenic

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Chromogenic FVIII, P

Aliases
Lists additional common names for a test, as an aid in searching

Adynovate (octogog alfa pegol)

Afstyla (rFVIII-SC)

Antihemophilic Factor (Recombinant)

Antihemophilic Factor (Recombinant), Fc Fusion Protein

Antihemophilic Factor (Recombinant), PEGylated

Antihemophilic Factor (Recombinant), Single Chain

Chromogenic

Eloctate (rFVIII-Fc)

Extend Half-life

Factor 8

Factor VIII

Kovaltry Antihemophilic Factor (Recombinant)

Long Acting glycoPEGylated

Nuwiq (simoctocog alfa)

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This assay is indicated in situations where there is a clinical suspicion of hemophilia A diagnosis, but the 1-stage Factor VIII (FVIII) assay is normal. However, recent guidelines also recommend this assay be performed in addition to the 1-stage assay in the initial workup of hemophilia A.

 

Testing for autoantibodies to FVIII in the presence of a low FVIII activity may be clinically indicated. For adding on FVIII inhibitor, call 800-533-1710 within 7 days to assess if adequate plasma sample is available.

 

See Hemophilia Testing Algorithm in Special Instructions.

Specimen Type
Describes the specimen type validated for testing

Plasma Na Cit

Ordering Guidance

Coagulation testing is highly complex, often requiring the performance of multiple assays and correlation with clinical information. For that reason, a coagulation consultation is recommended.

Necessary Information

If a priority specimen, mark request form, give reason, and request a call-back.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Specimen Type: Platelet-poor plasma

Collection Container/Tube: Light-blue top (3.2% sodium citrate)

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions:

1. Specimen must be collected prior to factor replacement therapy.

2. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing in Special Instructions.

3. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.

4. Aliquot plasma into plastic vial leaving 0.25 mL in the bottom of centrifuged vial.

5. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C or, ideally, < or =-40 degrees C.

Additional Information:

1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.

2. Each coagulation assay requested should have its own vial.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis OK
Gross lipemia OK
Gross icterus OK
IV heparin contamination Reject

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Plasma Na Cit Frozen (preferred) 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Monitoring coagulation factor replacement therapy of selected extended half-life coagulation factor replacements

 

Aiding in the diagnosis of hemophilia A using a 2-stage assay, especially when the 1-stage assay was normal

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This assay is indicated in situations where there is a clinical suspicion of hemophilia A diagnosis, but the 1-stage Factor VIII (FVIII) assay is normal. However, recent guidelines also recommend this assay be performed in addition to the 1-stage assay in the initial workup of hemophilia A.

 

Testing for autoantibodies to FVIII in the presence of a low FVIII activity may be clinically indicated. For adding on FVIII inhibitor, call 800-533-1710 within 7 days to assess if adequate plasma sample is available.

 

See Hemophilia Testing Algorithm in Special Instructions.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Factor VIII (FVIII) is synthesized in the endothelial cells of the liver and, perhaps, in other tissues. It is a coagulation cofactor that circulates bound to von Willebrand factor and is part of the intrinsic coagulation pathway. The biological half-life is 9 to 18 hours (average is 12 hours).

 

Congenital FVIII deficiency is inherited in a recessive X-linked manner and results in hemophilia A, which has an incidence of 1 in 10,000 live male births. Patients with severe deficiency (<1%) experience spontaneous bleeding episodes (eg, hemarthrosis, deep-tissue bleeding, etc), whereas patients with moderate or mild deficiency (>1%) typically experience post-trauma or surgical bleeding.

 

FVIII activity assays (FVIII:C) are performed to diagnose hemophilia A and to monitor FVIII replacement therapy. FVIII:C assays are typically 1-stage clotting assays. However, there is a subset of patients with mild hemophilia A who have shown discrepantly low results when measured with the 2-stage (chromogenic) assay, indicating that testing patients with a mild bleeding history with both a 1- and 2-stage assay would aid in diagnosis. In addition, there are new treatment options using long-acting glycoPEGylated products. Pharmacokinetic studies are showing that ideal monitoring of patients should be performed by the 2-stage chromogenic assay.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

55.0-200.0%

 

Chromogenic Factor VIII activity generally correlates with the one-stage FVIII activity. In full term/premature neonates, infants, children, and adolescents the one-stage FVIII activity* is similar to adults. However, no similar data for chromogenic FVIII activity are available.(Appel JTH 2012;10:2254)

 

*See Pediatric Hemostasis References section in Coagulation Guidelines for Specimen Handling and Processing in Special Instructions.

Interpretation
Provides information to assist in interpretation of the test results

Factor VIII deficiency may be seen in congenital hemophilia A, acquired (autoimmune) hemophilia A, or von Willebrand disease (congenital and acquired). Laboratory artifacts that may result in artificially reduced factor VIII include samples collected in EDTA, instead of citrate, or heparin contamination of the plasma sample.

 

Elevated factor VIII may be seen in acute or chronic inflammatory states or excess factor VIII replacement therapy.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Excess heparin and dilution contamination due to improper specimen collection through an intravenous access device may result in artifactually decreased results.

 

The 1-stage and chromogenic factor VIII (FVIII) assay results should correlate in the normal population but may be discordant in the hemophilia population and when measuring FVIII replacement.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Rodgers SE, Duncan EM, Sobieraj-Teague M, Lloyd JV: Evaluation of three automated chromogenic FVIII kits for the diagnosis of mild discrepant haemophilia A. Int J Lab Hematol. 2009 Apr;31(2):180-188

2. Kitchen S, Beckman H, Katterle Y, et al: BAY 81-8973, a full-length recombinant factor VIII: results from an International comparative laboratory field study. Haemophilia. 2016 May;22(3):e192-199. doi: 10.1111/hae.12925

3. Peyvandi F, Oldenburg J, Friedman KD: A critical appraisal of one-stage and chromogenic assays of factor VIII activity. J Thromb Haemost. 2016 Feb;14(2):248-261

4. Dodt J, Hubbard AR, Wicks SJ, et al: Potency determination of factor VIII and factor IX for new product labelling and postinfusion testing: challenges for caregivers and regulators. Haemophilia. 2015 Jul;21(4):543-549

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Description
Describes how the test is performed and provides a method-specific reference

The Chromogenic Factor VIII assay is performed on the Instrumentation Laboratory ACL TOP 700 using the CRYOcheck Chromogenic Factor VIII kit. In this 2-stage assay, patient plasma is diluted and combined with reagents containing bovine factor X, human factors IXa and IIa, calcium chloride, and phospholipids. The factor VIII in the patient's plasma aids in the activation of factor X to factor Xa. After a specified incubation period, chromogenic substrate is added at which time, the factor Xa, present from the previous step, hydrolyzes the substrate into peptide and p-nitroaniline (pNA). The color produced by the release of pNA is measured photometrically at 405 nm and is proportional to the factor VIII in the sample.(Package insert: CRYOcheck Chromogenic Factor VIII. Precision BioLogic Inc; Rev V04 06/2020)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 3 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

85130

LOINC® Information

Test Id Test Order Name Order LOINC Value
CHF8 Chromogenic FVIII, P 49865-9
Result Id Test Result Name Result LOINC Value
Result LOINC Value Tooltip
CHF8 Chromogenic FVIII, P 49865-9

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports