Diagnostic Use
An abnormal pattern of serum transferrin isoforms is found in congenital disorders of glycosylation (also called carbohydrate-deficient glycoprotein or CDG disorders).
These rare conditions are the result of enzyme defects in the post-translational glycosylation of proteins. Most are associated with developmental delay, and they may present with dysmorphic features, mental retardation, neurological deficits, and enteropathy.
Specific enzyme tests are required if the transferrin isoform pattern is suggestive of an abnormal pattern. If indicated, these follow-up tests can be performed at WCH in Adelaide.
See beta-2 transferrin for detecting leakage of CSF in nasal or ear secretions.
Direct detection at 200 nm in capillaries yields relative concentrations (percentages) of individual transferrin isoforms, and especially the calibrated percentage of disialotransferrin (CDT-IFCC).
– The upper limit of the reference interval (according to the IFCC working group) is 1.7 %.
=> CDT-IFCC ≤ 1.7 % : normal result.
– The proposed cut-off value is 2.0 % for forensic use (this value is based upon the upper reference limit plus the expended uncertainty of the
measurement).
=> CDT-IFCC > 2.0 % : For clinical purposes, values above 2 % are consistent with alcohol abuse or excessive alcohol consumption (according to
the IFCC working group).
– CDT-IFCC > 1.7 % and ≤ 2.0 %: inconclusive result (electrophoretic pattern with “NC” labeling). In this interval, the results do not permit to conclude
Test Method
Capillary electrophoresis
Limitations / Interference
Some monoclonal components or high polyclonal background.
Fibrinogen and haemolyzed samples,
Anticoagulants (EDTA, Heparin)
Aged or improperly sorted samples,
Liver injuries (serious, end stage disease)