Original ArticlesThe Nose Knows… or Does it? Olfactory Reference Syndrome in Patients Presenting for Assessment of Unusual Body OdorMcNiven, Vanda MD*; Mamane, Sarah MD†; Zai, Gwyneth MD, PhD‡; So, Joyce MD, PhD†‡§Author Information *Division of Clinical and Metabolic Genetics, The Hospital for Sick Children; †The Fred A. Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital; ‡Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto; and §Department of Medicine, University of Toronto, Toronto, Ontario, Canada. Send reprint requests to Joyce So, MD, PhD, The Fred A. Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital, 60 Murray St, Toronto, Ontario, Canada M5T 3L9. E-mail: firstname.lastname@example.org. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.jonmd.com). The Journal of Nervous and Mental Disease: March 2019 - Volume 207 - Issue 3 - p 145-151 doi: 10.1097/NMD.0000000000000933 Buy SDC Metrics Abstract Olfactory reference syndrome (ORS) is a rarely diagnosed psychiatric disorder in which individuals falsely believe that they emit an offensive body odor. This retrospective cohort study characterizes the clinical and demographic features of 54 individuals who presented to a Canadian genetics clinic for query trimethylaminuria (TMAU), an inherited disorder in which a pungent fishy odor is produced. The majority (83%) were found to have a likely diagnosis of ORS and a high rate (73.3%) of concomitant psychiatric disorders; only two patients were diagnosed with TMAU. This study highlights the genetics clinic as an unexpected and major ascertainment point for ORS, and shows that ORS can be differentiated from TMAU by age of onset (~28 years), odor characterization (refuse-related), and the presence of associated comorbid psychiatric diagnoses. There is a low diagnostic rate of ORS, attesting to the need for improved education and awareness. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.