PP12.15 – 2538: Therapeutic interventions for movement disorders in children with inborn errors of metabolism: What is the evidence?

Abstract

Objective Movement disorders (MD) are common symptoms in patients with inborn errors of metabolism (IEM). Based on a recent study, these symptoms seem to have serious impact on quality of life and daily functioning. Therefore knowledge about the optimal treatment is crucial. However, up till now a clear overview of the evidence for the efficacy and safety of therapeutic interventions for MD in IEM is lacking, in particular for the pediatric population. Methods A systematic literature search in Pubmed and Embase was performed to identify all articles reporting the effect of therapeutic interventions for MD in children with IEM. Results 288 papers were included, describing 63 different IEM. The most common observed MD were dystonia, ataxia and myoclonus. The effect on MD of disease specific treatments, primary aimed at the underlying condition (e.g. dietary measures), was mostly restricted to prevention with only mixed success. In the case of already existing MD the role of disease specific treatment is minimal. An exception is formed by neurotransmitter disorders, in this group resolving the biochemical defect usually leads to a dramatic improvement of the MD. When disease specific treatment lacks or fails, symptomatic therapies can be applied. In particular for dystonia, without excluding other MD, there are several effective therapeutic options available, of which trihexyfenidyl (Artane) and botulin toxin injections are amongst the most successful. In severe cases neurosurgical intervention in the form of deep brain stimulation is an option, although experiences in patients with IEM are still limited. Conclusion This is the first study reviewing the evidence for MD therapies in children with IEM. Most evidence consists of relatively small case reports. However, putting all data together gives valuable insight in which treatment options might work, and which not. Our overview provides a more rational basis for treatment choices in clinical practice.