Trimethylaminuria (fish malodour syndrome): a “benign” genetic condition with major psychosocial sequelae

Helen Mountain, Joanna M Brisbane, Amanda J Hooper, John R Burnett and Jack Goldblatt
Med J Aust 2008; 189 (8): . || doi: 10.5694/j.1326-5377.2008.tb02126.x
Published online: 20 October 2008

To the Editor: We report the case of a 41-year-old woman who sought medical opinion about an unpleasant body odour, first noticed when she was 7 years old. After experiencing ridicule, distress, shame, anxiety and low self-esteem during her school years, she first consulted a doctor about the problem at the age of 17 years, then again 2 years later, followed by a further four doctors over the next 20 years. All dismissed her concerns, and she was repeatedly told that she had a hygiene neurosis. Investigations and treatments during this time included being “sniffed”, vaginal swabs and vaginal cauterisation. Finally, a general practitioner referred her to a dermatologist, who consulted a microbiologist, and the diagnosis of trimethylaminuria (TMAU), or fish malodour syndrome, was confirmed by urinalysis. Now having a name for her condition, she found an Internet-based support foundation and referred herself for genetic counselling.

  • 1 Genetic Services of Western Australia, Perth, WA.
  • 2 Department of Core Clinical Pathology and Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth, WA.
  • 3 University of Western Australia, Perth, WA.

  • 1. Treacy EP, Akerman BR, Chow LM, et al. Mutations of the flavin-containing monooxygenase gene (FMO3) cause trimethylaminuria, a defect in detoxification. Hum Mol Genet 1998; 7: 839-845.
  • 2. Mitchell SC, Smith RL. Trimethylaminuria: the fish malodor syndrome. Drug Metab Dispos 2001; 29: 517-521.
  • 3. Wilcken B. Acid soaps in the fish odour syndrome [letter]. BMJ 1993; 307: 1497.
  • 4. Walker V. The fish odour syndrome. BMJ 1993; 307: 639-640.
  • 5. Ayesh R, Mitchell SC, Zhang A, Smith RL. The fish odour syndrome: biochemical, familial, and clinical aspects. BMJ 1993; 307: 655-657.


remove_circle_outline Delete Author
add_circle_outline Add Author

Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Online responses are no longer available. Please refer to our instructions for authors page for more information.