NoFact Immunodepleted Plasmas

Assay Type

Factor Deficiencies

Description

Human plasma pools selectively depleted of single coagulation factors by immunoadsorption.

Intended Use

The NoFact Deficient Substrate Plasma is intended for the quantitative determination of that Factor in patients suspected of having a congenital or acquired deficiency of this coagulation protein.

Uses

NoFact factor deficient plasmas are used in Factor assays using the PT or APTT.

Ordering Information

Intrinsic Pathway factors tested with the APTT

Catalog #	Product	Kit Configuration	Regulatory Classification	Product Insert (PDF)
68-201	NoFact VIII	10 x 1 mL	510(k), CE	LL-4505_F NF8
69-201	NoFact IX	10 x 1 mL	510(k), CE	LL-4506_F NF9

Principle of the Test

Factor deficiencies are both congenital and acquired. Factor assays are convenient, functional clotting assays that provide a quantitative determination of activity. A dilution of the patient sample is added to the NoFact depleted plasma of the factor of interest and run in a PT (for the extrinsic and common pathway factors) or in an APTT (for the intrinsic factors). The NoFact factor deficient plasma provides the remaining clotting factors while the patient sample is the sole source of the factor of interest. Under these conditions the clot time is inversely proportional to the concentration of the active factor in the patient sample.

Factor activity assays are calibrated with a plasma of known concentration of the factor of interest. PlasmaRef ARN is one of a variety of commercially available calibrators or reference plasmas, including nationally and internationally recognized consensus standards, with defined factor activities.

Reporting Units

Factor activity assays are reported in % Activity, where 100% activity is the activity assumed to be present in pooled normal plasma.

Handbooks and Guidelines

Functional Assays for Factors VIII, IX, XI, XII, Prekallikrein, and HMWK, pages 206-210, and Functional Assays for Factors II, V, VII, and X, pages 210-212, in Lapasota et. al., The Clinical Hemostasis Handbook, Year Book Medical Publishers, 1989. This handbook is no longer in print, but many pathologists have a copy.
Rogers G, “Testing for Inherited Bleeding Disorders”, in Laboratory Hemostasis: A Practical Guide for Pathologists, Bennet S et. al. editors, Springer 2007.
Krishnan J, Chapter 6, “Coagulation Testing”, in An Algorithmic Approach to Hemostasis Testing, Kottke Marchant ed., CAP Press, 2008
Kitchen S and Preston F, Chapter 9 “Assays of factor VIII and other clotting factors”, in Quality in Laboratory Hemostasis and Thrombosis, Kitchen, Olson, and Preston ed., Wiley-Blackwell, 2009.
Clinical Laboratory Standards Institute, “Determination of Factor Coagulant Activities; Approved Guideline”, CLSI document H48-A, 1997.
Clinical Laboratory Standards Institute, “One-Stage Prothrombin Time (PT) Test and Activated Partial Thromboplastin Time (APTT) Test; Approved Guideline – Second Edition”, CLSI document H47-A2, 2008.