IGF1 and Protein-losing enteropathy: Manifestations of PMM2-CDG are multisystemic and include psychomotor retardation, seizures, cardiomyopathy, coagulopathies, protein-losing enteropathy, liver disease, poor feeding, and failure to thrive.6 A combination of poor nutritional status and impairment of the growth hormone (GH)–insulin-like growth factor-1 (IGF-1) cascade is suggested as the cause of failure to thrive.4,5