Olfactory delusional syndrome

To the Editor,

Olfactory delusional syndrome (ODS) has also been termed olfactory reference syndrome. Published descriptions of this syndrome date back to the late 1800s. Pryse-Phillips (1971) characterised a large case series and coined the term for this group of patients. It is a condition in which individuals erroneously believe that they emit an unpleasant, foul, or offensive body odour from the mouth, genitals, rectum, or skin (American Psychiatric Association, 2000). Occasionally, patients report emitting non-bodily odours, such as ammonia, the smell of detergent, or rotten onions. This belief is accompanied by ideas or delusions that other people take special notice of the odour in a negative way, resulting in repetitive behaviour which impairs functioning.

A 25-year-old engineer presented with the complaint that a bad odour had been emanating from his body over the past 3 years, becoming progressively worse. The onset occurred one evening when a friend remarked that he ‘smelt bad’. Upset by this, he began to use deodorants every day. Over the next few months, he came to believe that a foul odour, akin to a ‘burnt smell’, originated from his armpits and thigh folds. He felt his colleagues rubbed their noses when he passed by, that co-passengers on the bus turned away when they saw him, and that the office security guard sprayed room freshener around his cabin. He began to bathe twice daily, taking longer than usual, and used talcum powder and deodorant regularly. He moved out of shared accommodation to live alone. He lost 10 kg in weight as he felt being heavy increased the foul odour. He turned up irregularly for work and avoided friends, resulting in a restricted social life. He had consulted a physician and a dermatologist, with no relief. There was no significant past or family history, and he was premorbidly well adjusted.

On examination, he had an unshakable belief that his body was emanating a ‘burnt smell’, an olfactory delusion. He felt that others were looking at him, indicating that he smelt bad – ideas of reference. There were no other psychotic/depressive features or obsessive compulsive phenomena. His physical examination and all relevant investigations were normal. A diagnosis of ODS was made.

In conclusion, this article highlights that ODS has been variously considered as a variant of delusional disorder, social phobia (Suzuki et al., 2004), body dysmorphic disorder (Prazeres et al., 2010), and obsessive compulsive disorder (Stein et al., 1998). The diagnosis is usually missed and hence untreated. These individuals seek help from specialities other than psychiatry and tend to be symptomatic for a long period of time. Awareness in the medical community about this syndrome would ensure that they are offered adequate and timely help.