Congenital Disorder of Glycosylation, Type Ij

Clinical Characteristics
Ocular Features: 

Bilateral cataracts are present at birth.  Nystagmus, strabismus, and long eyelashes have been reported.

Systemic Features: 

This is a disorder of glycosylation important to the formation of glycoproteins and glycolipids.  Neurological signs such as tremor, clonus, and muscle fasiculations may be seen soon after birth.  Other neurological abnormalities eventually include psychomotor retardation, seizures, mental retardation, hyperexcitabilty, and ataxia.  Failure to thrive and feeding difficulties are evident early.  Progressive microcephaly is a feature.  Liver dysfunction can lead to coagulopathy and hypoproteinemia with hepatomegaly is sometimes present.  Some patients have facial anomalies, inverted nipples, and subcutaneous fat pads.  The MRI may show areas of brain atrophy, ischemia, and focal necrosis.

Longevity is limited with 2 of 3 reported patients dying within 2 years of life.

Genetics

This is a rare autosomal recessive disorder resulting from mutations in DPAGT1 (11q23.3) resulting in defective N-glycosylation.  There are numerous other types of glycosylation defects with variations in the clinical manifestations.

Treatment
Treatment Options: 

Treatment consists of fluid and caloric intake management.  Hypoproteinemia and coagulation defects may respond to oral mannose administration.

References
Article Title: 

References

W?orde AE, Reunert J, Rust S, Hertzberg C, Haverk?SSmper S, N?ornberg G, N?ornberg P, Lehle L, Rossi R, Marquardt T. Congenital disorder of glycosylation type Ij(CDG-Ij, DPAGT1-CDG): Extending the clinical and molecular spectrum of a rare disease. Mol Genet Metab. 2012 Jan 9. [Epub ahead of print]

PubMedID: 22304930

Wu X, Rush JS, Karaoglu D, Krasnewich D, Lubinsky MS, Waechter CJ, Gilmore R, Freeze HH. Deficiency of UDP-GlcNAc:Dolichol Phosphate N-Acetylglucosamine-1 Phosphate Transferase (DPAGT1) causes a novel congenital disorder of Glycosylation Type Ij. Hum Mutat. 2003 Aug;22(2):144-50.

PubMedID: 12872255