Carbohydrate-deficient Transferrin CDT

Alcohol consumption is very difficult to assess. There is widespread belief that individuals underreport their intake and there are no reliable laboratory tests available for definitive diagnosis of alcohol abuse. A combination of abnormalities in the plasma activity of gamma-glutamyl transferase (GGT or yGT), AST and reduction in erythrocyte mean cell volume (MCV) maybe useful and all are routine lab. tests. A potential marker of interest is carbohydrate-deficient transferrin (CDT) which is an abnormal isoform of serum transferrin arising due to defects in the attachment of carbohydrate chains to the protein core. Unfortunately, CDT is a somewhat specialized test, not performed by most laboratories. Other markers which have attracted some research interest are ethyl sulphate and ethyl glucuronide. Excretion in the urine of these metabolites occurs for up to 50 hours after binge drinking so they offer a useful index of recent heavy alcohol intake. 

A. Golka K, Wiese A. Carbohydrate-deficient transferrin (CDT)-a biomarker for long-term alcohol consumption. J Toxicol Environ Health B Crit Rev 2004 7 319-37. 

Qualitative modifications in the glycosylation of this protein occur after prolonged heavy alcohol consumption and also in patients with rare congenital disorders of glycosylation (CDG). Therefore, measurement of transferrin microheterogeneity has been used both as a biomarker for detection and follow-up of alcohol abuse [known as carbohydrate-deficient transferrin (CDT)]" and for diagnosis of CDG. This chapter will review the microheterogeneity of human transferrin and the methods used for the measurement of transferrin... 

Figure 6.1 Structural illustration of the major normal glycoforms of human serum transferrin and those being influenced by chronic alcohol abuse (carbohydrate-deficient transferrin CDT) and in congenital disorders of glycosylation (CDG)...

C. Colome, I. Ferrer, R. Artuch, M.A. Vilaseca, M. Pineda and P. Briones, Personal experience with the application of carbohydrate-deficient transferrin (CDT) assays to the detection of congenital disorders of glycosylation, Clin. Chem. Lab. Med., 38, 965-969 (2000). 

A. Helander, M. Fors and B. Zakrisson, Study of Axis-Shield new %CDT immunoassay for quantification of carbohydrate-deficient transferrin (CDT) in serum, Alcohol Alcohol., 36, 406 412 (2001). 

Hulsewe et al. 1997). Several of the plasma proteins that alter in hepatotoxicity include hhrinogen, haptoglobin, transferrin, ceruloplasmin, alphaj-macroglobulin, coagulation cascade and complement proteins, secretory IgA, carbohydrate deficient transferrin (CDT), and protein F (see Chapter 8). 

Martello, S. et al.. Determination of carbohydrate deficient transferrin (CDT) with capillary electrophoresis an inter laboratory comparison. Forensic Sci. Intemat., 141, 153, 2004. 

A. Helander, J.P. Bergstrom, Determination of carbohydrate-deficient transferrin in human serum using the Bio-Rad% CDT by HPLC test, Clin Chim. Acta, 187-190 (2006). 

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