1. Division of Neurology, Department of Medicine Stellenbosch University Cape Town South Africa
2. Neurology Research Group, Division of Neurology, Department of Medicine University of Cape Town Cape Town South Africa
3. Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology University College London London United Kingdom
4. Department of Neuromuscular Diseases The National Hospital for Neurology and Neurosurgery London United Kingdom
5. Neurology Private Practice Hermanus South Africa
6. Faculty of Natural and Agricultural Sciences, Focus Area for Human Metabolomics North‐West University Potchefstroom South Africa