IFCC approved HPLC reference measurement procedure for the alcohol consumption biomarker carbohydrate-deficient transferrin (CDT): Its validation and use

Carbohydrate-deficient transferrin (CDT) is used as a biomarker of sustained high alcohol consumption. The currently available measurement procedures for CDT are based on various analytical techniques (HPLC, capillary electrophoresis, nephelometry), some differing in the definition of the analyte and using different reference intervals and cut-off values. The Working Group on Standardization of CDT (WG-CDT), initiated by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), has validated an HPLC candidate reference measurement procedure (cRMP) for CDT (% disialotransferrin to total transferrin based on peak areas), demonstrating that it is suitable as a reference measurement procedure (RMP) for CDT. Presented is a detailed description of the cRMP and its calibration. Practical aspects on how to treat genetic variant and so-called di-tri bridge samples are described. Results of method performance characteristics, as demanded by ISO 15189 and ISO 15193, are given, as well as the reference interval and measurement uncertainty and how to deal with that in routine use. The correlation of the cRMP with commercial CDT procedures and the performance of the cRMP in a network of laboratories are also presented. The performance of the CDT cRMP in combination with previously developed commutable calibrators allows for standardization of the currently available commercial measurement procedures for CDT. The cRMP has recently been approved by the IFCC and will be from now on be known as the IFCC-RMP for CDT, while CDT results standardized according to this RMP should be indicated as CDTIFCC. •Carbohydrate-deficient transferrin (CDT) is a serum transferrin glycoform profile seen in sustained high alcohol consumption•CDT has become an important clinical and forensic biomarker for detection and follow-up of chronic high alcohol use•A CDT reference measurement procedure (RMP) has been missing and field methods differ in results and reference intervals•To end this confusion, the IFCC founded a Working Group for standardization of CDT measurement (WG-CDT)•The WG-CDT defined the CDT measurand and selected an anion-exchange HPLC measurement procedure as candidate RMP (cRMP)•The WG-CDT has validated the cRMP according to ISO 15193 and established the measurement uncertainty and reference interval•Following IFCC approval of the validated cRMP and its description of use, the method will be known as the IFCC-RMP for CDT