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

Research output: Contribution to journalReview article


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.


  • Lisette H. Koens
  • Marina A.J. Tijssen
  • Fiete Lange
  • Bruce H.R. Wolffenbuttel
  • Alessandra Rufa
  • David S. Zee
  • Tom J. de Koning
External organisations
  • University Medical Center Groningen
  • University of Siena
  • Johns Hopkins Hospital
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Neurology


  • adult-onset, eye movement disorders, inborn errors of metabolism, movement disorders
Original languageEnglish
Pages (from-to)1844-1856
JournalMovement Disorders
Issue number12
Publication statusPublished - 2018 Dec
Publication categoryResearch
Externally publishedYes