Re-evaluation of the dysequilibrium syndrome.

Area of Science:

• Neurology
• Genetics
• Pediatrics

Background:

• Dysequilibrium syndrome (DES) is a rare neurological disorder.
• Historically diagnosed based on clinical symptoms.
• Advancements in neuroimaging and genetic testing necessitate re-evaluation.

Purpose of the Study:

• To re-evaluate middle-aged Swedish patients diagnosed with DES in childhood.
• To compare clinical and neuroimaging findings with DES associated with VLDLR gene mutations (DES-VLDLR).

Main Methods:

• Neurological examination and brain MRI were performed on six patients from five families.
• Serum carbohydrate-deficient transferrin (s-CDT) screening was conducted.
• VLDLR gene sequencing was performed.

Main Results:

• Five patients presented with non-progressive cerebellar ataxia, dysarthria, and short stature.
• Features characteristic of DES-VLDLR, such as mental retardation and strabismus, were inconsistent.
• No VLDLR mutations were found; MRI findings were variable, with one patient diagnosed with CDG-1a.

Conclusions:

• Clinical diagnosis of DES predates advanced neuroimaging and genetic analysis.
• Modern MRI and genetic testing are crucial for accurate DES diagnosis.
• Re-evaluation highlights the heterogeneity of DES and the importance of differential diagnosis.