A True Isolated Cognitive Relapse in Multiple Sclerosis.

Isolated cognitive relapses (ICRs) have been a matter of debate for the past few years. Currently, there is no clear consensus on such an entity, as cognitive decline usually accompanies typical multiple sclerosis (MS) relapses. Herein, we present the neuropsychological and neurophysiological manifestations of a patient who suddenly complained of confusion and memory loss, showing insight into her deficit, in absence of sensorimotor disturbances. Neuroimaging revealed a large tumefactive gadolinium-enhancing lesion localized in the left medial temporal lobe. The patient's symptoms persisted for months afterwards, despite corticosteroid treatment. We believe our patient experienced a true ICR. ICRs are rare entities in MS, but we should be alert to their existence in order to treat them promptly. Deepening their pathophysiology is equally important and neuropsychology combined with neurophysiology may be useful in this regard.