Since sometimes the core belief of ORS is not of delusional intensity, it is argued that considering the condition as a form of delusional disorder, as seems to occur in the DSM, is inappropriate. In one review, in 57% of cases the beliefs were fixed, held with complete conviction, and the individual could not be reassured that the odor was non existent. In 43% of cases the individual held the beliefs with less than complete conviction, and was able to varying degrees to consider the possibility that the odor was not existent.Other symptoms may be reported and are claimed to be related to the cause of the odor, such as malfunction of the anal sphincter, a skin disease, "diseased womb", stomach problems or other unknown organic disease. Excessive washing in ORS has been reported to cause the development of eczema. Referential ideas
People with ORS misinterpret the behavior of others to be related to the imagined odor (thoughts of reference). In one review, ideas of reference were present in 74% of cases. Usually, these involve misinterpretations of comments, gestures and actions of other people such that it is believed that an offensive smell from the individual is being referred to. These thoughts of reference are more pronounced in social situations which the individual with ORS may find stressful, such as public transport, crowded lift, workplace, classroom, etc. Example behaviors which are misinterpreted include coughing, sneezing, turning of the head, opening a window, facial expressions, sniffing, touching nose, scratching head, gestures, moving away, avoiding the person, whistling.
Diagnosis
Differential diagnoses
The differential diagnosis includes elastofibroma, fibrolipoma, desmoid-type fibromatoses, and nuchal fibrocartilaginous pseudotumor. Management
Simple excision is curative. However, in patients with Gardner syndrome, up to 45% will develop desmoid-type fibromatosis at other sites, and so this should be searched for and excluded. Patients can develop a recurrence, so follow-up is required. Epidemiology
This is a rare tumor, presenting over a wide age range, but usually in the 3rd to 5th decades of life. There is a slight male predilection, although this is not seen in syndrome associated patients. The most common site is the posterior neck, but may also be seen in other sites (extremities, lumbosacral area, buttocks, face). See also
Fibrous Lesions

References
Further reading
Lester D. R. Thompson; Bruce M. Wenig (2011). Diagnostic Pathology: Head and Neck: Published by Amirsys. Hagerstown, MD: Lippincott Williams & Wilkins. pp. 8:44–45. ISBN 978-1-931884-61-7.