Obsessive-compulsive disorder associated with parietal white matter multiple sclerosis plaques.

We report the case of a patient who developed obsessive-compulsive symptoms after being diagnosed with multiple sclerosis. In this patient, obsessive-compulsive symptoms deteriorated with the emergence of a right parietal white matter multiple sclerosis plaque. The involvement of parietal white matter abnormalities in the pathophysiology of obsessive-compulsive disorder remains largely unexplored. Our case report raises the possibility that parietal lobe white matter microstructure plays a role in mediating obsessions and compulsions through disruptions of the functional connectivity between cortical-cortical and/or cortical-subcortical brain regions implicated in the pathophysiology of obsessive-compulsive disorder.