The patient, a 59-year-old woman, had a history of postpartum depression at age 29. About 20 years before PD onset she had experienced pruritus and was briefly convinced she had scabies, although physicians discarded this diagnosis. She was diagnosed with PD at age 53. First-line treatment with piribedil, a dopaminergic agonist, was effective. Levodopa (plus carbidopa) was added 3 years later, and entacapone was added when a wearing-off effect developed. Her motor status has since remained fair (8 years after onset). One year after onset of PD, while on piribedil monotherapy, the patient experienced a transient hypomanic state with increased libido, and reported having masturbated with ice cubes. Shortly afterward, she complained of foul odors that she attributed to her vaginal secretions. This conviction gradually became stronger, and she started to suspect that her gut was also responsible. The patient was convinced that other people showed expressions of disgust or made covert comments, and she showed social avoidance. She transiently developed depressive symptoms, without fulfilling DSM-IV criteria for a major episode. She had anxiety with obsessional features but no compulsion. There were no other associated psychotic disorders, with the exception of transient visual hallucinations in dim light with preserved insight. Olfactory function, assessed with the 12-item Brief Smell Identification Test (Sensonics) was normal. Neuropsychological status, assessed with the Mattis Dementia Rating Scale, Frontal Assessment Battery, verbal fluencies tests, and a free and cued recall performance test, was normal. MRI of the brain was normal. The ORS was unaffected by the addition of clozapine (maximum daily dose 125 mg) and paroxetine (30 mg). Piribedil was withdrawn, the antiparkinsonian treatment consisting only in levodopa 100 mg/carbidopa 25 mg/entacapone 200 mg tid. This change had no effect on the ORS, which was still present 7 years after its onset.