[Acquired and developmental Gerstmann syndrome. Illustration from a patient with multiple sclerosis]

Gerstmann's syndrome (GS) is defined by a clinical tetrad including acalculia, finger anomia, left-right disorientation and agraphia. In this article, we describe the case of a 42-year-old woman suffering from an aggressive relapsing-remitting multiple sclerosis in which a systematic neuropsychological assessment revealed Gertsmann's syndrome amongst other cognitive disturbances. Brain MRI showed a high concentration of plaques within a left subcortical parietal region that has recently been considered as a crucial node for GS appearance. However, history, taking provided information suggesting that an important part of the GS, may have been present since childhood, evoking a possible neurodevelopmental origin in this patient. This article reviews the role of the GS concept in contemporary literature, with a special attention to pathophysiological hypotheses and to precautions necessary to study such cases.