Onset of MELAS due to the m.3243A > G mutation is early if the large phenotypic variability is considered

Abstract

With interest we read the article by Sunde et al. about a female with MELAS syndrome with onset at age 49 years and four stroke-like episodes (SLEs) during the first 2 years who was followed-up for 5 years [1]. We have the following comments and concerns. The morphological equivalent of a SLE is a stroke-like lesion on cerebral MRI during the acute stage. Only one MRI during the asymptomatic stage is described showing left occipital cystic encephalomalacia and white matter lesions [1]. No MRI figure is presented. The patient is reported to have had experienced four SLEs during the first 2 years after diagnosis [1]. Were ever typical abnormalities (DWI and ADC hyperintensity beyond a vascular territory) detected in the acute stage during any of these SLEs? Did these lesions change in a typical manner over time [2]? How did the authors exclude that the occipital lesion resulted from an ischemic stroke?