Eye movement disorders and neurological symptoms in late-onset inborn errors of metabolism

Lisette H Koens; Marina A J Tijssen; Fiete Lange; Bruce H R Wolffenbuttel; Alessandra Rufa; David S Zee; Tom J de Koning

doi:10.1002/mds.27484

Eye movement disorders and neurological symptoms in late-onset inborn errors of metabolism

Mov Disord. 2018 Dec;33(12):1844-1856. doi: 10.1002/mds.27484. Epub 2018 Nov 28.

Authors

Lisette H Koens¹, Marina A J Tijssen¹, Fiete Lange², Bruce H R Wolffenbuttel³, Alessandra Rufa⁴, David S Zee⁵, Tom J de Koning^{6

7}

Affiliations

¹ University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands.
² University of Groningen, University Medical Center Groningen, Department of Clinical Neurophysiology, Groningen, The Netherlands.
³ Department of Endocrinology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
⁴ Department of Medicine Surgery and Neurosciences, University of Siena, Eye tracking and Visual Application Lab (EVA Lab)-Neurology and Neurometabolic Unit, Siena, Italy.
⁵ Department of Neuroscience, Department of Ophthalmology, The Johns Hopkins University, The Johns Hopkins Hospital, Department of Neurology, Department of Otolaryngology-Head and Neck Surgery, Baltimore, Maryland, USA.
⁶ University of Groningen, Division of Metabolic Diseases, University Medical Center Groningen, Groningen, The Netherlands.
⁷ University of Groningen, Department of Genetics, University Medical Center Groningen, Groningen, The Netherlands.

Abstract

Inborn errors of metabolism in adults are still largely unexplored. Despite the fact that adult-onset phenotypes have been known for many years, little attention is given to these disorders in neurological practice. The adult-onset presentation differs from childhood-onset phenotypes, often leading to considerable diagnostic delay. The identification of these patients at the earliest stage of disease is important, given that early treatment may prevent or lessen further brain damage. Neurological and psychiatric symptoms occur more frequently in adult forms. Abnormalities of eye movements are also common and can be the presenting sign. Eye movement disorders can be classified as central or peripheral. Central forms are frequently observed in lysosomal storage disorders, whereas peripheral forms are a key feature of mitochondrial disease. Furthermore, oculogyric crisis is an important feature in disorders affecting dopamine syntheses or transport. Ocular motor disorders are often not reported by the patient, and abnormalities can be easily overlooked in a general examination. In adults with unexplained psychiatric and neurological symptoms, a special focus on examination of eye movements can serve as a relatively simple clinical tool to detect a metabolic disorder. Eye movements can be easily quantified and analyzed with video-oculography, making them a valuable biomarker for following the natural course of disease or the response to therapies. Here, we review, for the first time, eye movement disorders that can occur in inborn errors of metabolism, with a focus on late-onset forms. We provide a step-by-step overview that will help clinicians to examine and interpret eye movement disorders. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Keywords: adult-onset; eye movement disorders; inborn errors of metabolism; movement disorders.

Publication types

Review

MeSH terms

Age of Onset*
Delayed Diagnosis*
Eye Movements / physiology
Humans
Metabolism, Inborn Errors / diagnosis
Metabolism, Inborn Errors / physiopathology*
Movement Disorders / complications
Movement Disorders / diagnosis*
Movement Disorders / therapy
Ocular Motility Disorders / diagnosis
Ocular Motility Disorders / physiopathology*