|Values are valid only on day of printing.|
Congenital disorders of glycosylation (CDG) are a group of more than 45 inherited conditions affecting several steps in the glycosylation of proteins. CDG can present with a broad clinical spectrum from developmental delay to multiorgan involvement (eg, liver disease, developmental delay, failure to thrive, chronic diarrhea, abnormal subcutaneous fat distribution, retinitis pigmentosa, cutis laxa, etc.).
CDG are classified into 2 groups:
A third type- SLC35A2- was recently recognized with new genetic defects.
Transferrin and apolipoprotein CIII are abundant and highly glycosylated serum proteins. Abnormal transferrin or apolipoprotein CIII isoforms are typically observed in Type I and Type II CDG, respectively. Accordingly, structural analysis of these proteins in serum provides a fast and cost-effective screening test for CDGs and is indicated for the evaluation of patients with developmental delay, failure to thrive, unexplained liver dysfunction, stroke-like episodes, seizures and muscle hypotonia, regardless of the patient’s age. The absence of the classical findings of abnormal fat deposit and inverted nipples does not exclude CDG.