It Is Not Always Alcohol Abuse—A Transferrin Variant Impairing the CDT Test

    loading  Checking for direct PDF access through Ovid

Abstract

Aims

Elevated Carbohydrate-deficient transferrin (CDT) levels are used as a biomarker in order to screen for chronic alcohol abuse. Transferrin (Tf) variants can impair methods to measure elevated CDT levels such as high-performance liquid chromatography (HPLC). We present a Tf variant affecting the second glycosylation site of Tf and the complications it causes in diagnosing alcoholism.

Methods

A blood sample from a patient with suspected alcohol abuse was analyzed with HPLC, isoelectric focusing, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), immunoprecipitation and SDS-Page. Sanger sequencing of Tf was performed to detect Tf mutations.

Results

HPLC, SDS-Page and IEF showed a distinctly increased disialo-Tf fraction while the tetrasialo-Tf fraction was decreased, ESI-TOF-MS confirmed these results. Sanger sequencing revealed the Tf mutation c.1889 A>C, deleting a Tf glycosylations site and thereby causing elevated disialo-Tf levels.

Conclusions

Transferrin mutations can severely impair the diagnostics of chronic alcohol abuse by causing false positive results. This has to be considered when CDT screening is used to detect alcoholism.

Related Topics

    loading  Loading Related Articles