A case of late-onset OCD developing PLS and FTD

We describe a 64-year-old woman, suffering from late-onset obsessive-compulsive disorder (OCD) from the age of 57, who developed dysarthria and dysphagia, spastic diplegic, and proximal muscles weakness. Needle electromyography showed no active denervation. Neuropsychological evaluation showed intact cognitive functioning. We diagnosed upper motor neuron disease (MND), with no known genetic correlates. Brain magnetic resonance (MRI) detected bilateral hippocampal atrophy with sclerosis of right hippocampus. 18F-FDG positron emission tomography (PET) showed moderate right temporal cortex thinning. Six months later, motor and behavioral symptoms worsened. Neuropsychological examination revealed long-term memory deficit and executive dysfunction. MRI and PET evidenced severe worsening of atrophy in temporal and frontal lobes. Four years later a definitive diagnosis of primary lateral sclerosis (PLS) and FTD was made. To our knowledge, this is the first report of PLS and FTD with OCD at onset.