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.