This is a rare metabolic disorder resulting from a deficiency in an enzyme important in the synthesis of specialized types of proteins and fats. This results in a severe generalized disorder involving many parts of the body.
The major manifestations of this condition result from abnormalities in the brain and nervous system. Infants soon after birth have unusual movements in their muscles including tremors. They fail to thrive normally and feed poorly. Gradually the head size falls behind the age curve. Often within months seizures develop, they fall behind developmental milestones, and they are often unsteady. Psychomotor retardation can lead to mental retardation. Children are often hyperexcitable. The liver does not function normally and may become enlarged. The MRI scan often reveals focal areas of brain damage. The liver is sometimes enlarged and may be dysfunctional causing fluid loss or abnormal blood clotting.
Only a few patients with this disorder have been reported and they were severely limited in their function. Longevity was reduced to several years.
There are many types of glycosylation defects and not all have the same clinical features.
This is an autosomal recessive disorder that results when both genes that code for an essential enzyme are altered (mutated). Parents are clinically normal since they carry only one copy of the mutation but when both members of a couple are carriers, each of their children have a 25% risk of inheriting both copies.
The diagnosis is most likely made by a pediatric neurologist with gene testing. However, the early signs can point to the suspected diagnosis during evaluation by a pediatrician or ophthalmologist. There is no treatment that cures this disorder but some of their symptoms can be managed by careful adjustment of fluid and calorie intake.