Re-evaluation of the dysequilibrium syndrome

Objectives - To re-evaluate middle-aged Swedish patients diagnosed with dysequilibrium syndrome (DES) in childhood and to compare their clinical and neuroimaging features to DES with VLDLR gene mutations (DES-VLDR). Materials and methods - Six patients from five families underwent neurological examination and magnetic resonance imaging (MRI) of the brain. Blood samples from the patients were screened for serum carbohydrate-deficient transferrin (s-CDT; disialotransferrin). The very-low-density lipoprotein receptor (VLDLR) gene was sequenced. Results - Five patients had non-progressive cerebellar ataxia (NPCA), dysarthria and short stature. Mental retardation and strabismus, characteristic for DES-VLDLR, were inconsistent among our patients. None of our patients had VLDLR mutations or MRI findings characteristic of DES-VLDLR. MRI findings were variable from a normal cerebellum to marked cerebellar hypoplasia or atrophy and signal intensity changes. One patient was diagnosed with congenital disorder of glycosylation type 1a (CDG-1a). Conclusions - DES was originally coined on mainly clinical grounds before MRI and specific genetic tests were available, both of which should be used to arrive at an appropriate diagnosis.